Tomcat ClassNotFoundException: com.mysql.cj.jdbc.Driver 5C

连不上mysql数据库 jar包都导入好了 却不幸
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手机Music是有WAV文件的 已经测出来list出有数据 但不显示 04-15 21:50:02.787 10805-10805/? I/System.out: WavInfo : 205.wav
04-15 21:50:02.787 10805-10805/? I/System.out: WavInfo : 206.wav
04-15 21:50:02.787 10805-10805/? I/System.out: WavInfo : 207.wav
04-15 21:50:02.787 10805-10805/? I/System.out: WavInfo : 208.wav

改变ListView的宽度属性, android;width="mathc_parent"

一条数据都不显示么,还是只显示一条

首先,你的代码应该是不完整的,第三行应为 private List> list; 后面的list实例化应为 list = new ArrayList<>();
然后Map也需要指定,声明并实例化: Map map = new HashMap(); 这样适配器才可以找到你指定的Map中的key。
代码修改完试试看。

ZXHL_hxf
xiaofeng-huang ...代码居然被缺省掉了···
大约 2 年之前 回复

在MyListView.setAdapter(adapter);后面你要刷新啊列表,
执行代码adapter.notifydatasetchanged();

建议先setAdapter
再做数据的初始化
再数据初始化完成后adapter.notifydatasetchanged();

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java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driver已在lib下添加jar包还是报错怎么办

在网上好了很多的问题 都没有解决,针对web,大家用的都是的在tomcat下的lib里添加mysql-connector的jar包 但是还是没有解决 还是连接不上,也在url里面添加后缀了 package jdbc; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; import java.sql.Statement; public class JDBCDemo { private static final String URL="jdbc:mysql://localhost:3306/db4?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=Hongkong"; private static final String USERNAME="root"; private static final String PWD="root"; public static void update() {//增删改 Connection connection=null; Statement stmt =null; try { //导入驱动,加载具体驱动类 Class.forName("com.mysql.cj.jdbc.Driver");//加载具体的驱动类 //与数据库建立连接 connection=DriverManager.getConnection(URL,USERNAME,PWD); //增删改 stmt = connection.createStatement(); String sql="insert into student values(4,'kxk','123')"; int result = stmt.executeUpdate(sql); //处理结果:显示受影响行数 System.out.println(result); }catch (ClassNotFoundException e) { e.printStackTrace(); }catch (Exception e) { e.printStackTrace(); }finally { if(stmt!=null) { try { stmt.close(); }catch (SQLException e) { e.printStackTrace(); } } if(connection!=null) { try { connection.close(); }catch (SQLException e) { e.printStackTrace(); } } } } public static void main(String[] args) { update(); } } 报错还是 java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driver at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:338) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:264) 不知道哪里出现了问题,求助

Stacktrace:] with root cause java.lang.ClassNotFoundException: com.mysql.jdbc.Driver

org.apache.jasper.JasperException: 在 [17] 行处理 [find stu_1.jsp] 时发生异常 14: String url2="?user="+userName+"&password="+userPwd; 15: String url3="&useUnicode=true&characterEncoding=utf-8"; 16: String url=url1+url2+url3; 17: Class.forName(driverName); 18: Connection conn=DriverManager.getConnection(url); 19: String sql="select * from stu_info"; 20: PreparedStatement pstmt=conn.prepareStatement(sql); Stacktrace: org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:626) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:500) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329) javax.servlet.http.HttpServlet.service(HttpServlet.java:741) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) Root Cause javax.servlet.ServletException: java.lang.ClassNotFoundException: com.mysql.jdbc.Driver org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:666) org.apache.jsp.find_0020stu_005f1_jsp._jspService(find_0020stu_005f1_jsp.java:201) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:71) javax.servlet.http.HttpServlet.service(HttpServlet.java:741) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:477) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329) javax.servlet.http.HttpServlet.service(HttpServlet.java:741) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) Root Cause java.lang.ClassNotFoundException: com.mysql.jdbc.Driver org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1365) org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1188) org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:122) org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:59) java.lang.Class.forName0(Native Method) java.lang.Class.forName(Class.java:264) org.apache.jsp.find_0020stu_005f1_jsp._jspService(find_0020stu_005f1_jsp.java:135) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:71) javax.servlet.http.HttpServlet.service(HttpServlet.java:741) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:477) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329) javax.servlet.http.HttpServlet.service(HttpServlet.java:741) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ):注意 主要问题的全部 stack 信息可以在 server logs 里查看 Stacktrace:] with root cause java.lang.ClassNotFoundException: com.mysql.jdbc.Driver at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1365) at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1188) at org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:122) at org.apache.jasper.servlet.JasperLoader.loadClass(JasperLoader.java:59) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:264) at org.apache.jsp.find_0020stu_005f1_jsp._jspService(find_0020stu_005f1_jsp.java:135) at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:71) at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:477) at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385) at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329) at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:690) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) at 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servlet调用dao层报错java.lang.ClassNotFoundException: com.mysql.cj.jdbc如何解决?

servlet调用dao层报错java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driv,,相关的jar包已经导入,并且用主函数传递数据在测试coverage时能够正常运行 ``` ``` ``` ``` //处理登录请求 public static void checkUser(ServletRequest req, ServletResponse res) { //获取请求信息 String name =(String) req.getParameter("name"); String pwd =(String) req.getParameter("pwd"); System.out.println("浏览器获取"+name+":"+pwd); //处理请求信息 userServiceImpl us=new userServiceImpl(); user u=us.checkUserService(name, pwd); //响应处理结果 System.out.println(u); //请求去转发 //重定向 //直接响应 } } ``` ``` public user cherDao(String name,String pwd) { //声明jdbc对象 Connection conn=null; PreparedStatement ps=null; ResultSet rs=null; //声明变量 user u=null; try { //加载驱动 System.out.println("加载驱动前"); Class.forName("com.mysql.cj.jdbc.Driver"); System.out.println("加载驱动后"); //获取连接 conn=DriverManager.getConnection("jdbc:mysql://localhost:3306/zyn?useSSL=false&serverTimezone=UTC","root","123456"); //创建sql命令 String sql="select * from user where uname=? and pwd=?"; //创建sql命令对象 ps=conn.prepareStatement(sql); //给占位符赋值 ps.setString(1,name); ps.setString(2,pwd); //执行sql rs=ps.executeQuery(); //遍历结果 System.out.println("遍历结果前"); while (rs.next()) { System.out.println("DAO层"); u=new user(); u.setUid(rs.getInt("uid")); u.setUname(rs.getString("uname")); u.setPwd(rs.getString("pwd")); u.setSex(rs.getInt("sex")); u.setAge(rs.getInt("age")); u.setBirth(rs.getString("birth")); } } catch (Exception e) { // TODO: handle exception e.printStackTrace(); } finally { try { rs.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } try { ps.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } try { conn.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } //返回结果 return u; } } ``` ```

LAMP18.04下javaweb项目用JDBC连接mysql5.7.28失败,报错java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driver

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Could not get JDBC Connection; com.mysql.cj.jdbc.Driver?

四月 17, 2019 2:15:44 上午 org.apache.catalina.core.StandardWrapperValve invoke 严重: Servlet.service() for servlet [taotao-manager] in context with path [] threw exception [Request processing failed; nested exception is org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: com.mysql.cj.jdbc.Driver ### The error may exist in com/taotao/mapper/TbItemMapper.xml ### The error may involve com.taotao.mapper.TbItemMapper.selectByPrimaryKey ### The error occurred while executing a query ### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: com.mysql.cj.jdbc.Driver] with root cause java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driver at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1702) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1547) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:264) at com.alibaba.druid.util.JdbcUtils.createDriver(JdbcUtils.java:518) at com.alibaba.druid.pool.DruidDataSource.init(DruidDataSource.java:583) at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:915) at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:911) at com.alibaba.druid.pool.DruidDataSource.getConnection(DruidDataSource.java:98) at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111) at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77) at org.mybatis.spring.transaction.SpringManagedTransaction.openConnection(SpringManagedTransaction.java:81) at org.mybatis.spring.transaction.SpringManagedTransaction.getConnection(SpringManagedTransaction.java:67) at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:279) at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:72) at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:59) at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:267) at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:137) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:96) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:77) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:108) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:102) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectOne(DefaultSqlSession.java:66) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:358) at com.sun.proxy.$Proxy30.selectOne(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.selectOne(SqlSessionTemplate.java:163) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:68) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:52) at com.sun.proxy.$Proxy31.selectByPrimaryKey(Unknown Source) at com.taotao.service.impl.ItemServiceImpl.getItemById(ItemServiceImpl.java:24) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317) at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99) at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:267) at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207) at com.sun.proxy.$Proxy34.getItemById(Unknown Source) at com.taotao.controller.ItemController.getItemById(ItemController.java:27) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at 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org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:943) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:877) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:966) at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:857) at javax.servlet.http.HttpServlet.service(HttpServlet.java:621) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:842) at javax.servlet.http.HttpServlet.service(HttpServlet.java:728) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1041) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:603) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) db.properties配置为 jdbc.driver=com.mysql.cj.jdbc.Driver jdbc.url=jdbc:mysql://localhost:3306/taotao?useSSL=false&serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=UTF8 jdbc.username=root jdbc.password=123 连接池配置 <context:property-placeholder location="classpath:resource/db.properties" /> <!-- 数据库连接池 --> <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close"> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <property name="driverClassName" value="${jdbc.driver}" /> <!-- <property name="maxActive" value="10" /> <property name="minIdle" value="5" /> --> </bean> <!-- 让spring管理sqlsessionfactory 使用mybatis和spring整合包中的 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 加载mybatis的全局配置文件 --> <property name="configLocation" value="classpath:mybatis/SqlMapConfig.xml" /> <!-- 数据库连接池 --> <property name="dataSource" ref="dataSource" /> </bean> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="com.taotao.mapper" /> </bean>

Could not load driverClass com.mysql.jbdc.Driver,配置好jar了还是找不到

自学线上商城的java web 项目。今天一个下午都在调这个bug,也试过调试jar包,也有重新配置Tomcat与mysql的连接池 我也有把jdbc的包放在jdk的lib文件夹下,然后增加classpath,jre的ext都试过 还看了新的jdbc是com.mysql.cj.jdbc.Driver也试过,似乎都没什么用 在maven和Tomcat的列表里都有jdbc的jar包,包括我自己有新build path也增加了这些jar包,而且我把好几个版本的都放上去了(不知道会不会是这个影响,不过加了也删不掉),pom.xml里面配的是截图中的8.0.17 ![图片说明](https://img-ask.csdn.net/upload/201908/02/1564760377_14775.png) ********** 如果需要更多信息我也可以再加,感激不尽 ## 报错信息如下:********** ``` 8月 02, 2019 11:30:38 下午 com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource getPoolManager 信息: Initializing c3p0 pool... com.mchange.v2.c3p0.ComboPooledDataSource [ acquireIncrement -> 3, acquireRetryAttempts -> 2, acquireRetryDelay -> 1000, autoCommitOnClose -> false, automaticTestTable -> null, breakAfterAcquireFailure -> false, checkoutTimeout -> 10000, connectionCustomizerClassName -> null, connectionTesterClassName -> com.mchange.v2.c3p0.impl.DefaultConnectionTester, dataSourceName -> 1hge162a4n0lvdz1eiiv1j|6ccdb29f, debugUnreturnedConnectionStackTraces -> false, description -> null, driverClass -> com.mysql.jbdc.Driver, factoryClassLocation -> null, forceIgnoreUnresolvedTransactions -> false, identityToken -> 1hge162a4n0lvdz1eiiv1j|6ccdb29f, idleConnectionTestPeriod -> 0, initialPoolSize -> 3, jdbcUrl -> jdbc:mysql://localhost:3306/todoList?useUnicode=true&characterEncoding=utf8&serverTimezone=GMT&useSSL=false, maxAdministrativeTaskTime -> 0, maxConnectionAge -> 0, maxIdleTime -> 0, maxIdleTimeExcessConnections -> 0, maxPoolSize -> 30, maxStatements -> 0, maxStatementsPerConnection -> 0, minPoolSize -> 10, numHelperThreads -> 3, numThreadsAwaitingCheckoutDefaultUser -> 0, preferredTestQuery -> null, properties -> {password=******, user=******}, propertyCycle -> 0, testConnectionOnCheckin -> false, testConnectionOnCheckout -> false, unreturnedConnectionTimeout -> 0, usesTraditionalReflectiveProxies -> false ] 8月 02, 2019 11:30:38 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded 警告: Could not load driverClass com.mysql.jbdc.Driver java.lang.ClassNotFoundException: com.mysql.jbdc.Driver at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) at java.base/java.lang.Class.forName0(Native Method) at java.base/java.lang.Class.forName(Class.java:332) at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) 8月 02, 2019 11:30:38 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded 警告: Could not load driverClass com.mysql.jbdc.Driver java.lang.ClassNotFoundException: com.mysql.jbdc.Driver at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) at java.base/java.lang.Class.forName0(Native Method) at java.base/java.lang.Class.forName(Class.java:332) at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) 8月 02, 2019 11:30:38 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded 警告: Could not load driverClass com.mysql.jbdc.Driver java.lang.ClassNotFoundException: com.mysql.jbdc.Driver at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) at java.base/java.lang.Class.forName0(Native Method) at java.base/java.lang.Class.forName(Class.java:332) at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) 8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded 警告: Could not load driverClass com.mysql.jbdc.Driver java.lang.ClassNotFoundException: com.mysql.jbdc.Driver at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) at java.base/java.lang.Class.forName0(Native Method) at java.base/java.lang.Class.forName(Class.java:332) at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) 8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded 警告: Could not load driverClass com.mysql.jbdc.Driver java.lang.ClassNotFoundException: com.mysql.jbdc.Driver at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) at java.base/java.lang.Class.forName0(Native Method) at java.base/java.lang.Class.forName(Class.java:332) at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) 8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded 警告: Could not load driverClass com.mysql.jbdc.Driver java.lang.ClassNotFoundException: com.mysql.jbdc.Driver at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) at java.base/java.lang.Class.forName0(Native Method) at java.base/java.lang.Class.forName(Class.java:332) at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) 8月 02, 2019 11:30:40 下午 com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run 警告: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@40eddbb0 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (2). Last acquisition attempt exception: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown database 'todolist' at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500) at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481) at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) at com.mysql.jdbc.Util.getInstance(Util.java:408) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:944) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3978) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3914) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:871) at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1714) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1224) at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2199) at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2230) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2025) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:778) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500) at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481) at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:386) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) 8月 02, 2019 11:30:40 下午 com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run 警告: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@45eae662 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (2). Last acquisition attempt exception: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown database 'todolist' at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500) at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481) at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) at com.mysql.jdbc.Util.getInstance(Util.java:408) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:944) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3978) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3914) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:871) at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1714) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1224) at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2199) at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2230) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2025) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:778) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500) at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481) at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:386) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) 8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded 警告: Could not load driverClass com.mysql.jbdc.Driver java.lang.ClassNotFoundException: com.mysql.jbdc.Driver at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) at java.base/java.lang.Class.forName0(Native Method) at java.base/java.lang.Class.forName(Class.java:332) at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) 8月 02, 2019 11:30:40 下午 com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask run 警告: com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask@6f8071b9 -- Acquisition Attempt Failed!!! Clearing pending acquires. While trying to acquire a needed new resource, we failed to succeed more than the maximum number of allowed acquisition attempts (2). Last acquisition attempt exception: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Unknown database 'todolist' at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500) at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481) at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) at com.mysql.jdbc.Util.getInstance(Util.java:408) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:944) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3978) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3914) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:871) at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1714) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1224) at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2199) at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2230) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2025) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:778) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47) at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500) at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481) at com.mysql.jdbc.Util.handleNewInstance(Util.java:425) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:386) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:134) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) 8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded 警告: Could not load driverClass com.mysql.jbdc.Driver java.lang.ClassNotFoundException: com.mysql.jbdc.Driver at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) at java.base/java.lang.Class.forName0(Native Method) at java.base/java.lang.Class.forName(Class.java:332) at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) 8月 02, 2019 11:30:40 下午 com.mchange.v2.c3p0.DriverManagerDataSource ensureDriverLoaded 警告: Could not load driverClass com.mysql.jbdc.Driver java.lang.ClassNotFoundException: com.mysql.jbdc.Driver at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583) at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) at java.base/java.lang.Class.forName0(Native Method) at java.base/java.lang.Class.forName(Class.java:332) at com.mchange.v2.c3p0.DriverManagerDataSource.ensureDriverLoaded(DriverManagerDataSource.java:100) at com.mchange.v2.c3p0.DriverManagerDataSource.getConnection(DriverManagerDataSource.java:132) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:182) at com.mchange.v2.c3p0.WrapperConnectionPoolDataSource.getPooledConnection(WrapperConnectionPoolDataSource.java:171) at com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool$1PooledConnectionResourcePoolManager.acquireResource(C3P0PooledConnectionPool.java:137) at com.mchange.v2.resourcepool.BasicResourcePool.doAcquire(BasicResourcePool.java:1014) at com.mchange.v2.resourcepool.BasicResourcePool.access$800(BasicResourcePool.java:32) at com.mchange.v2.resourcepool.BasicResourcePool$AcquireTask.run(BasicResourcePool.java:1810) at com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread.run(ThreadPoolAsynchronousRunner.java:547) ```

HTTP Status 500 - javax.servlet.ServletException

type Exception report message javax.servlet.ServletException: java.lang.NoClassDefFoundError: org/apache/lucene/search/Query description The server encountered an internal error that prevented it from fulfilling this request. exception org.apache.jasper.JasperException: javax.servlet.ServletException: java.lang.NoClassDefFoundError: org/apache/lucene/search/Query org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:502) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:412) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260) javax.servlet.http.HttpServlet.service(HttpServlet.java:723) root cause javax.servlet.ServletException: java.lang.NoClassDefFoundError: org/apache/lucene/search/Query org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:865) org.apache.jasper.runtime.PageContextImpl.handlePageException(PageContextImpl.java:794) org.apache.jsp.s_jsp._jspService(s_jsp.java:218) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) javax.servlet.http.HttpServlet.service(HttpServlet.java:723) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260) javax.servlet.http.HttpServlet.service(HttpServlet.java:723) root cause java.lang.NoClassDefFoundError: org/apache/lucene/search/Query org.apache.jsp.s_jsp._jspService(s_jsp.java:120) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) javax.servlet.http.HttpServlet.service(HttpServlet.java:723) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260) javax.servlet.http.HttpServlet.service(HttpServlet.java:723) root cause java.lang.ClassNotFoundException: org.apache.lucene.search.Query org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1680) org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526) java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320) org.apache.jsp.s_jsp._jspService(s_jsp.java:120) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) javax.servlet.http.HttpServlet.service(HttpServlet.java:723) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:388) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260) javax.servlet.http.HttpServlet.service(HttpServlet.java:723) note The full stack trace of the root cause is available in the Apache Tomcat/6.0.37 logs.

jdbc连接数据库问题 结果连接出错 求大神指点啊 急急急

![图片说明](https://img-ask.csdn.net/upload/201608/22/1471834934_145091.png) 安装数据库出现这个问题 我找到相应的路径之后重新运行了一下那个bat文件 然后我自己写了一套jdbc public class ConnectOracle { static{ try { Class.forName("oracle.jdbc.driver.OracleDriver"); } catch (ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public static Connection getCon(){ Connection con = null; try{ con = DriverManager.getConnection("jdbc:oracle:thin:@localhost:1521:orcl","system","123"); }catch(Exception e){ e.printStackTrace(); } return con ; } public static void main(String[] args) { Connection con = ConnectOracle.getCon(); System.out.println(con); } } 运行后的结果如图 ![图片说明](https://img-ask.csdn.net/upload/201608/22/1471834930_863214.png) 请问这是什么问题?

请教一下,到底我的mapper.xml哪里出错了,弄不明白为什么找不到我写的log类

## update一下经大佬提点后如何解决的 可能因为我曾用粗暴的方法改动过Log.java的类名,导致Log类编译出问题了,编译后类文件夹内根本没有Log.class文件。于是我又粗暴地delete了Log类重写了一次,果然没问题了。 顺便百度了一下如何修改类名 https://zhidao.baidu.com/question/340215163.html ## 原问题如下 小白入门程序媛,这个是一个mybatis的关于银行转账的小练习 在写log部分之前,我写的account部分测试过是没有问题的,转账的业务也成功了的。现在是想增加一个记录日志的操作,在数据库log表格添加转账记录,并且利用log4j在硬盘生成log file中记录转账信息。 可是按照同样的套路写了了log实体类后再写logmapper.xml,却出现了以下的错误,后来干脆连mybatis中的别名的部分都去掉了,直接在mapper.xml中使用完整的类名,还是说找不到我写的log类。实在搞不懂是namespace出错了还是怎么滴。。。。 ## 错误信息如下: ``` 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: Server version: Apache Tomcat/8.5.42 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: Server built: Jun 4 2019 20:29:04 UTC 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: Server number: 8.5.42.0 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: OS Name: Windows 10 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: OS Version: 10.0 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: Architecture: amd64 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: Java Home: C:\Program Files\Java\jdk1.8.0_201\jre 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: JVM Version: 1.8.0_201-b09 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: JVM Vendor: Oracle Corporation 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: CATALINA_BASE: D:\eclipse-workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: CATALINA_HOME: D:\apache-tomcat-8.5.42 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: Command line argument: -Dcatalina.base=D:\eclipse-workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: Command line argument: -Dcatalina.home=D:\apache-tomcat-8.5.42 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: Command line argument: -Dwtp.deploy=D:\eclipse-workspace\.metadata\.plugins\org.eclipse.wst.server.core\tmp0\wtpwebapps 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: Command line argument: -Djava.endorsed.dirs=D:\apache-tomcat-8.5.42\endorsed 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.VersionLoggerListener log 信息: Command line argument: -Dfile.encoding=UTF-8 七月 13, 2019 8:47:00 下午 org.apache.catalina.core.AprLifecycleListener lifecycleEvent 信息: Loaded APR based Apache Tomcat Native library [1.2.21] using APR version [1.6.5]. 七月 13, 2019 8:47:00 下午 org.apache.catalina.core.AprLifecycleListener lifecycleEvent 信息: APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true]. 七月 13, 2019 8:47:00 下午 org.apache.catalina.core.AprLifecycleListener lifecycleEvent 信息: APR/OpenSSL configuration: useAprConnector [false], useOpenSSL [true] 七月 13, 2019 8:47:00 下午 org.apache.catalina.core.AprLifecycleListener initializeSSL 信息: OpenSSL successfully initialized [OpenSSL 1.1.1a 20 Nov 2018] 七月 13, 2019 8:47:00 下午 org.apache.coyote.AbstractProtocol init 信息: Initializing ProtocolHandler ["http-nio-8080"] 七月 13, 2019 8:47:00 下午 org.apache.tomcat.util.net.NioSelectorPool getSharedSelector 信息: Using a shared selector for servlet write/read 七月 13, 2019 8:47:00 下午 org.apache.coyote.AbstractProtocol init 信息: Initializing ProtocolHandler ["ajp-nio-8009"] 七月 13, 2019 8:47:00 下午 org.apache.tomcat.util.net.NioSelectorPool getSharedSelector 信息: Using a shared selector for servlet write/read 七月 13, 2019 8:47:00 下午 org.apache.catalina.startup.Catalina load 信息: Initialization processed in 828 ms 七月 13, 2019 8:47:00 下午 org.apache.catalina.core.StandardService startInternal 信息: Starting service [Catalina] 七月 13, 2019 8:47:00 下午 org.apache.catalina.core.StandardEngine startInternal 信息: Starting Servlet Engine: Apache Tomcat/8.5.42 七月 13, 2019 8:47:01 下午 org.apache.jasper.servlet.TldScanner scanJars 信息: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time. 七月 13, 2019 8:47:02 下午 org.apache.coyote.AbstractProtocol start 信息: Starting ProtocolHandler ["http-nio-8080"] 七月 13, 2019 8:47:02 下午 org.apache.coyote.AbstractProtocol start 信息: Starting ProtocolHandler ["ajp-nio-8009"] 七月 13, 2019 8:47:02 下午 org.apache.catalina.startup.Catalina start 信息: Server startup in 1377 ms 七月 13, 2019 8:47:32 下午 org.apache.catalina.core.StandardWrapperValve invoke 严重: Servlet.service() for servlet [yan.ibbie.servlet.TransferServlet] in context with path [/bank] threw exception org.apache.ibatis.exceptions.PersistenceException: ### Error building SqlSession. ### The error may exist in yan/ibbie/mapper/logmapper.xml ### Cause: org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'yan/ibbie/mapper/logmapper.xml'. Cause: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'yan.ibbie.pojo.Log'. Cause: java.lang.ClassNotFoundException: Cannot find class: yan.ibbie.pojo.Log at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30) at org.apache.ibatis.session.SqlSessionFactoryBuilder.build(SqlSessionFactoryBuilder.java:80) at org.apache.ibatis.session.SqlSessionFactoryBuilder.build(SqlSessionFactoryBuilder.java:64) at yan.ibbie.service.Impl.AccountServiceImpl.transfer(AccountServiceImpl.java:23) at yan.ibbie.servlet.TransferServlet.service(TransferServlet.java:36) at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:493) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:660) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:798) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:808) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1498) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:748) Caused by: org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'yan/ibbie/mapper/logmapper.xml'. Cause: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'yan.ibbie.pojo.Log'. Cause: java.lang.ClassNotFoundException: Cannot find class: yan.ibbie.pojo.Log at org.apache.ibatis.builder.xml.XMLConfigBuilder.parseConfiguration(XMLConfigBuilder.java:121) at org.apache.ibatis.builder.xml.XMLConfigBuilder.parse(XMLConfigBuilder.java:99) at org.apache.ibatis.session.SqlSessionFactoryBuilder.build(SqlSessionFactoryBuilder.java:78) ... 26 more Caused by: org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'yan/ibbie/mapper/logmapper.xml'. Cause: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'yan.ibbie.pojo.Log'. Cause: java.lang.ClassNotFoundException: Cannot find class: yan.ibbie.pojo.Log at org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:120) at org.apache.ibatis.builder.xml.XMLMapperBuilder.parse(XMLMapperBuilder.java:92) at org.apache.ibatis.builder.xml.XMLConfigBuilder.mapperElement(XMLConfigBuilder.java:373) at org.apache.ibatis.builder.xml.XMLConfigBuilder.parseConfiguration(XMLConfigBuilder.java:119) ... 28 more Caused by: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'yan.ibbie.pojo.Log'. Cause: java.lang.ClassNotFoundException: Cannot find class: yan.ibbie.pojo.Log at org.apache.ibatis.builder.BaseBuilder.resolveClass(BaseBuilder.java:118) at org.apache.ibatis.builder.xml.XMLStatementBuilder.parseStatementNode(XMLStatementBuilder.java:68) at org.apache.ibatis.builder.xml.XMLMapperBuilder.buildStatementFromContext(XMLMapperBuilder.java:135) at org.apache.ibatis.builder.xml.XMLMapperBuilder.buildStatementFromContext(XMLMapperBuilder.java:128) at org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:118) ... 31 more Caused by: org.apache.ibatis.type.TypeException: Could not resolve type alias 'yan.ibbie.pojo.Log'. Cause: java.lang.ClassNotFoundException: Cannot find class: yan.ibbie.pojo.Log at org.apache.ibatis.type.TypeAliasRegistry.resolveAlias(TypeAliasRegistry.java:120) at org.apache.ibatis.builder.BaseBuilder.resolveAlias(BaseBuilder.java:149) at org.apache.ibatis.builder.BaseBuilder.resolveClass(BaseBuilder.java:116) ... 35 more Caused by: java.lang.ClassNotFoundException: Cannot find class: yan.ibbie.pojo.Log at org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:200) at org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:89) at org.apache.ibatis.io.Resources.classForName(Resources.java:261) at org.apache.ibatis.type.TypeAliasRegistry.resolveAlias(TypeAliasRegistry.java:116) ... 37 more ``` ## mybatis.xml如下: ``` <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <settings> <setting name="logImpl" value="LOG4J"/> </settings> <!-- default填默认使用的environment的id --> <environments default="default"> <!-- environment标签声明一个环境 --> <environment id="default"> <!-- type="JDBC"表示使用原生JDBC事务 --> <transactionManager type="JDBC"></transactionManager> <dataSource type="POOLED"> <property name="driver" value="com.mysql.cj.jdbc.Driver"/> <property name="url" value="jdbc:mysql://localhost:3306/ssm?serverTimezone=GMT%2B8"/> <property name="username" value="root"/> <property name="password" value="1233210"/> </dataSource> </environment> </environments> <mappers> <mapper resource="yan/ibbie/mapper/accountmapper.xml"/> <mapper resource="yan/ibbie/mapper/logmapper.xml"/> </mappers> </configuration> ``` ## accountmapper.xml如下: ``` <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="yan.ibbie.mapper.accountmapper"> <!-- 根据账号和密码查询账户信息 --> <select id="selByAccnoPassword" resultType="yan.ibbie.pojo.Account" parameterType="yan.ibbie.pojo.Account"> select * from account where accno=#{accNo} and password=#{password} </select> <!-- 根据账号和姓名查询账户信息 --> <select id="selByAccnoName" resultType="yan.ibbie.pojo.Account" parameterType="yan.ibbie.pojo.Account"> select * from account where accno=#{accNo} and name=#{name} </select> <!-- 根据账号修改账户余额 --> <update id="updBalanceByAccno" parameterType="yan.ibbie.pojo.Account"> update account set balance=balance+#{balance} where accno=#{accNo} </update> </mapper> ``` ## logmapper.xml如下: ``` <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="yan.ibbie.mapper.logmapper"> <insert id="insLog" parameterType="yan.ibbie.pojo.Log"> insert into log values(default,#{accOut},#{accIn},#{money}) </insert> </mapper> ``` ## yan.ibbie.pojo.log如下 ``` package yan.ibbie.pojo; public class Log { private int id; private String accOut; private String accIn; private double money; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getAccOut() { return accOut; } public void setAccOut(String accOut) { this.accOut = accOut; } public String getAccIn() { return accIn; } public void setAccIn(String accIn) { this.accIn = accIn; } public double getMoney() { return money; } public void setMoney(double money) { this.money = money; } } ``` ## AccountServiceImpl如下: ``` package yan.ibbie.service.Impl; import java.io.IOException; import java.io.InputStream; import java.util.Date; import org.apache.ibatis.io.Resources; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder; import com.sun.istack.internal.logging.Logger; import yan.ibbie.pojo.Account; import yan.ibbie.pojo.Log; import yan.ibbie.service.AccountService; public class AccountServiceImpl implements AccountService { @Override public int transfer(Account accIn, Account accOut) throws IOException { InputStream is = Resources.getResourceAsStream("mybatis.xml"); SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is); SqlSession session = factory.openSession(); Account accOutSelect = session.selectOne("yan.ibbie.mapper.accountmapper.selByAccnoPassword",accOut); if (accOutSelect!=null) { if(accOutSelect.getBalance()>=accOut.getBalance()) { Account accInSelect = session.selectOne("yan.ibbie.mapper.accountmapper.selByAccnoName",accIn); if (accInSelect!=null) { accIn.setBalance(accOut.getBalance()); accOut.setBalance(-accOut.getBalance()); int index=session.update("yan.ibbie.mapper.accountmapper.updBalanceByAccno", accOut); index += session.update("yan.ibbie.mapper.accountmapper.updBalanceByAccno",accIn); if (index==2) { Log log = new Log(); log.setAccOut(accOut.getAccNo()); log.setAccIn(accIn.getAccNo()); log.setMoney(accIn.getBalance()); session.update("yan.ibbie.mapper.logmapper.insLog", log); Logger logger = Logger.getLogger(AccountServiceImpl.class); logger.info(log.getAccOut()+"给"+log.getAccIn()+ "在"+new Date().toLocaleString()+"转了"+log.getMoney()); session.commit(); session.close(); return SUCCESS; }else { session.rollback(); session.close(); return ERROR; } }else { return ACCOUNT_NAME_NOT_MATCH; } }else { return ACCOUNT_BALANCE_NOT_ENOUGHT; } }else { return ACCOUNT_PASSWORD_NOT_MATCH; } } } ```

JDBC工具类连接时的问题

在我使用JDBC连接数据库的时候总是报NoClassDefFoundError错误,我在经过多次百度无果后。决定向各位大佬请教一下。 * 错误的具体原因为: Exception in thread "main" java.lang.NoClassDefFoundError: Could not initialize class cn.itcast.jdbc.JDBCUtils # JDBCDome /** *通过键盘录入用户和密码 * 判断用户是否登录成功 */ public class jdbcDemo9 { public static void main(String[] args) { //1.键盘录入,接受用户名和密码 Scanner sc = new Scanner(System.in); System.out.println("请输入用户名"); String username = sc.nextLine(); System.out.println("请输入密码"); String password = sc.nextLine(); //2.调用方法 boolean flag = new jdbcDemo9().login(username,password); //3.判断结果输出不同语句 if (flag){ System.out.println("登录成功"); }else { System.out.println("用户名或密码错误"); } } /** * 登录方法 */ public boolean login(String username,String password){ if (username==null || password==null){ return false; } Connection conn = null; Statement stmt = null; ResultSet rs =null; //连接数据库判断是否登录成功 try { conn = JDBCUtils.getConnection();//在这里debug的时候显示conn=null //2定义sql String sql = "select * from user where username = '"+username+"' and password = '"+password+"'"; //3获取执行sql的对象 stmt = conn.createStatement(); //4执行查询 rs = stmt.executeQuery(sql); //5.判断 return rs.next(); //如果有下一行,返回true } catch (SQLException e) { e.printStackTrace(); } finally { JDBCUtils.close(rs,stmt,conn); } return false; } } ## JDBCUtils ``` /** * JDBC工具类 */ //工具类的方法应该都是静态的,这样方便我们去调用 public class JDBCUtils { private static String url; private static String user ; private static String password; private static String driver; /** * 文件的读取,只需要读取一次就可以拿到值:使用静态代码块 */ static { //获取资源文件,获取值 try { //1、Propertits集合类 Properties pro = new Properties(); //获取src路径下的文件的方式:ClassLoader 类加载器 ,要获取Classlodar,要获取他对应的字节码文件 ClassLoader classLoader = JDBCUtils.class.getClassLoader(); URL resource = classLoader.getResource("jdbc.propertits"); String path = resource.getPath(); //返回字符串路径 //System.out.println(path); //2加载文件 pro.load(new FileReader(path)); //3获取属性,赋值 url = pro.getProperty("url"); user = pro.getProperty("user"); password = pro.getProperty("password"); driver = pro.getProperty("driver"); //注册驱动 Class.forName(driver); //之前写的是:com.mysql.cj.jdbc.Driver } catch (IOException e) { e.printStackTrace(); } catch (ClassNotFoundException e) { e.printStackTrace(); } } /** * 获取连接 * @return 连接对象释放资源 */ public static Connection getConnection() throws SQLException { return DriverManager.getConnection(url,user,password); } /** * 释放资源 * @param stmt * @param conn */ public static void close(ResultSet rs,Statement stmt, Connection conn){ if (rs!=null){ try { rs.close(); } catch (SQLException e) { e.printStackTrace(); } } if (stmt!=null){ try { stmt.close(); } catch (SQLException e) { e.printStackTrace(); } } if (conn!=null){ try { conn.close(); } catch (SQLException e) { e.printStackTrace(); } } } } ``` # 配置文件 url=jdbc:mysql://localhost:3306/db4?useSSL=false&serverTimezone=UTC user=root password=nana980801 driver=com.mysql.cj.jdbc.Driver ``` ```

springboot 整合mybatis 报错提示包扫描不进去

![图片说明](https://img-ask.csdn.net/upload/201908/14/1565777159_224084.png) ``` package com.liupeng; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; import tk.mybatis.spring.annotation.MapperScan; @SpringBootApplication() @MapperScan(basePackages = "com.liupeng.mapper") public class Application { public static void main(String[] args) { SpringApplication.run(Application.class,args); } } ``` ``` package com.liupeng.service; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import com.liupeng.mapper.UserMapper; import com.liupeng.pojo.User; @Service(value = "Userservice") public class UserServiceImpl implements Userservice { @Autowired private UserMapper userMapper; @Override public User getNamePassword(User user) { // TODO Auto-generated method stub return userMapper.selectgetNamePassword(user); } @Override public void saveUser(User user) { // TODO Auto-generated method stub } } ``` mapper.xml ``` <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="com.liupeng.mapper.UserMapper"> ``` ``` #------------------配置虚拟文件路径--start------------------------------ spring.http.multipart.location=E:\Java\java代码\Chaoyang\src\main\resources #-----------------------------------------数据库--start---------------------- spring.datasource.driver-class-name=com.mysql.cj.jdbc.Drive spring.datasource.url=jdbc:mysql://localhost:3306/ssm_mybatis?serverTimezone=GMT spring.datasource.username=root spring.datasource.password=liupeng.123 spring.datasource.druid.stat-view-servlet.allow=true #获取连接等待超时时间 spring.datasource.dbcp2.max-wait-millis=60000 #mybatis配置 mybatis.type-aliases-package=com.liupeng.pojo mybatis.mapper-locations=classpath:mapper/*.xml #通用Mapper配置 #mapper.mappers=com.liupeng.utils.MyMapper #mapper.not-empty=false #mapper.identity=MYSQL #分页插件配置 pagehelper.helperDialect=mysq1 pagehelper.reasonable=true pagehelper.supportMethodsArguments=true pagehelper.params=count=countSql #文件上传配置 spring.http.multipart.maxFileSize=100Mb spring.http.multipart.maxRequestSize=1000Mb #配置api端口号 server.port=8080 #tomcat的URI编码 server.tomcat.uri-encoding=UTF-8 ``` ``` ERROR [main] - Application startup failed org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'registLoginController': Unsatisfied dependency expressed through field 'userservice'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'Userservice': Unsatisfied dependency expressed through field 'userMapper'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userMapper' defined in file [E:\Java\java代码\Chaoyang\target\classes\com\liupeng\mapper\UserMapper.class]: Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [tk/mybatis/mapper/autoconfigure/MapperAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [E:\Java\java代码\Chaoyang\target\classes\mapper\UserMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. Cause: java.lang.IllegalArgumentException: Result Maps collection already contains value for com.liupeng.mapper.UserMapper.BaseResultMap at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:586) at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:364) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1268) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:551) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:481) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:312) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:308) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:756) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:542) at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:123) at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:666) at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:353) at org.springframework.boot.SpringApplication.run(SpringApplication.java:300) at org.springframework.boot.SpringApplication.run(SpringApplication.java:1082) at org.springframework.boot.SpringApplication.run(SpringApplication.java:1071) at com.liupeng.Application.main(Application.java:13) Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'Userservice': Unsatisfied dependency expressed through field 'userMapper'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userMapper' defined in file [E:\Java\java代码\Chaoyang\target\classes\com\liupeng\mapper\UserMapper.class]: Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [tk/mybatis/mapper/autoconfigure/MapperAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [E:\Java\java代码\Chaoyang\target\classes\mapper\UserMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. Cause: java.lang.IllegalArgumentException: Result Maps collection already contains value for com.liupeng.mapper.UserMapper.BaseResultMap at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:586) at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:87) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:364) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1268) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:551) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:481) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:312) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:308) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:211) at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1131) at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1059) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:583) ... 19 more Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userMapper' defined in file [E:\Java\java代码\Chaoyang\target\classes\com\liupeng\mapper\UserMapper.class]: Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [tk/mybatis/mapper/autoconfigure/MapperAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [E:\Java\java代码\Chaoyang\target\classes\mapper\UserMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. Cause: java.lang.IllegalArgumentException: Result Maps collection already contains value for com.liupeng.mapper.UserMapper.BaseResultMap at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireByType(AbstractAutowireCapableBeanFactory.java:1361) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1253) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:551) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:481) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:312) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:308) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:211) at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1131) at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1059) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:583) ... 32 more Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [tk/mybatis/mapper/autoconfigure/MapperAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [E:\Java\java代码\Chaoyang\target\classes\mapper\UserMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. Cause: java.lang.IllegalArgumentException: Result Maps collection already contains value for com.liupeng.mapper.UserMapper.BaseResultMap at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:599) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1177) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1072) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:511) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:481) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:312) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:308) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:211) at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1131) at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1059) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireByType(AbstractAutowireCapableBeanFactory.java:1346) ... 43 more Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [E:\Java\java代码\Chaoyang\target\classes\mapper\UserMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. Cause: java.lang.IllegalArgumentException: Result Maps collection already contains value for com.liupeng.mapper.UserMapper.BaseResultMap at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:189) at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:588) ... 55 more Caused by: org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [E:\Java\java代码\Chaoyang\target\classes\mapper\UserMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. Cause: java.lang.IllegalArgumentException: Result Maps collection already contains value for com.liupeng.mapper.UserMapper.BaseResultMap at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:523) at org.mybatis.spring.SqlSessionFactoryBean.afterPropertiesSet(SqlSessionFactoryBean.java:380) at org.mybatis.spring.SqlSessionFactoryBean.getObject(SqlSessionFactoryBean.java:547) at tk.mybatis.mapper.autoconfigure.MapperAutoConfiguration.sqlSessionFactory(MapperAutoConfiguration.java:155) at tk.mybatis.mapper.autoconfigure.MapperAutoConfiguration$$EnhancerBySpringCGLIB$$90d064bb.CGLIB$sqlSessionFactory$1(<generated>) at tk.mybatis.mapper.autoconfigure.MapperAutoConfiguration$$EnhancerBySpringCGLIB$$90d064bb$$FastClassBySpringCGLIB$$b0514ca6.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228) at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:358) at tk.mybatis.mapper.autoconfigure.MapperAutoConfiguration$$EnhancerBySpringCGLIB$$90d064bb.sqlSessionFactory(<generated>) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:162) ... 56 more Caused by: org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. Cause: java.lang.IllegalArgumentException: Result Maps collection already contains value for com.liupeng.mapper.UserMapper.BaseResultMap at org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:120) at org.apache.ibatis.builder.xml.XMLMapperBuilder.parse(XMLMapperBuilder.java:92) at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:521) ... 69 more Caused by: java.lang.IllegalArgumentException: Result Maps collection already contains value for com.liupeng.mapper.UserMapper.BaseResultMap at org.apache.ibatis.session.Configuration$StrictMap.put(Configuration.java:872) at org.apache.ibatis.session.Configuration$StrictMap.put(Configuration.java:844) at org.apache.ibatis.session.Configuration.addResultMap(Configuration.java:626) at org.apache.ibatis.builder.MapperBuilderAssistant.addResultMap(MapperBuilderAssistant.java:214) at org.apache.ibatis.builder.ResultMapResolver.resolve(ResultMapResolver.java:47) at org.apache.ibatis.builder.xml.XMLMapperBuilder.resultMapElement(XMLMapperBuilder.java:285) at org.apache.ibatis.builder.xml.XMLMapperBuilder.resultMapElement(XMLMapperBuilder.java:252) at org.apache.ibatis.builder.xml.XMLMapperBuilder.resultMapElements(XMLMapperBuilder.java:244) at org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:116) ... 71 more ```

maven工程报以下错误,初始化失败、监听器出现问题等 这是怎么回事?

启动maven工程后报以下错误 09:24:39,799 ERROR ContextLoader:316 - Context initialization failed org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in URL [jar:file:/E:/repository_boot/com/yezi/yezi_common_service/1.0-SNAPSHOT/yezi_common_service-1.0-SNAPSHOT.jar!/applicationContext-dao.xml]: Cannot create inner bean 'com.github.pagehelper.PageHelper#3bc66802' of type [com.github.pagehelper.PageHelper] while setting bean property 'plugins' with key [0]; nested exception is org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.github.pagehelper.PageHelper] for bean with name 'com.github.pagehelper.PageHelper#3bc66802' defined in URL [jar:file:/E:/repository_boot/com/yezi/yezi_common_service/1.0-SNAPSHOT/yezi_common_service-1.0-SNAPSHOT.jar!/applicationContext-dao.xml]; nested exception is java.lang.ClassNotFoundException: com.github.pagehelper.PageHelper at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:327) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:124) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveManagedArray(BeanDefinitionValueResolver.java:389) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:155) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1605) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1357) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:578) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:501) at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:741) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:869) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:409) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:291) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:103) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4939) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5434) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) Caused by: org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.github.pagehelper.PageHelper] for bean with name 'com.github.pagehelper.PageHelper#3bc66802' defined in URL [jar:file:/E:/repository_boot/com/yezi/yezi_common_service/1.0-SNAPSHOT/yezi_common_service-1.0-SNAPSHOT.jar!/applicationContext-dao.xml]; nested exception is java.lang.ClassNotFoundException: com.github.pagehelper.PageHelper at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1380) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:473) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:312) ... 26 more Caused by: java.lang.ClassNotFoundException: com.github.pagehelper.PageHelper at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1702) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1547) at org.springframework.util.ClassUtils.forName(ClassUtils.java:274) at org.springframework.beans.factory.support.AbstractBeanDefinition.resolveBeanClass(AbstractBeanDefinition.java:437) at org.springframework.beans.factory.support.AbstractBeanFactory.doResolveBeanClass(AbstractBeanFactory.java:1428) at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1372) ... 28 more 十月 17, 2019 9:24:39 上午 org.apache.catalina.core.StandardContext listenerStart 严重: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in URL [jar:file:/E:/repository_boot/com/yezi/yezi_common_service/1.0-SNAPSHOT/yezi_common_service-1.0-SNAPSHOT.jar!/applicationContext-dao.xml]: Cannot create inner bean 'com.github.pagehelper.PageHelper#3bc66802' of type [com.github.pagehelper.PageHelper] while setting bean property 'plugins' with key [0]; nested exception is org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.github.pagehelper.PageHelper] for bean with name 'com.github.pagehelper.PageHelper#3bc66802' defined in URL [jar:file:/E:/repository_boot/com/yezi/yezi_common_service/1.0-SNAPSHOT/yezi_common_service-1.0-SNAPSHOT.jar!/applicationContext-dao.xml]; nested exception is java.lang.ClassNotFoundException: com.github.pagehelper.PageHelper at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:327) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:124) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveManagedArray(BeanDefinitionValueResolver.java:389) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:155) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1605) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1357) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:578) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:501) at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:741) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:869) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:409) at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:291) at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:103) at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4939) at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5434) at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559) at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) Caused by: org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.github.pagehelper.PageHelper] for bean with name 'com.github.pagehelper.PageHelper#3bc66802' defined in URL [jar:file:/E:/repository_boot/com/yezi/yezi_common_service/1.0-SNAPSHOT/yezi_common_service-1.0-SNAPSHOT.jar!/applicationContext-dao.xml]; nested exception is java.lang.ClassNotFoundException: com.github.pagehelper.PageHelper at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1380) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:473) at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:312) ... 26 more Caused by: java.lang.ClassNotFoundException: com.github.pagehelper.PageHelper at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1702) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1547) at org.springframework.util.ClassUtils.forName(ClassUtils.java:274) at org.springframework.beans.factory.support.AbstractBeanDefinition.resolveBeanClass(AbstractBeanDefinition.java:437) at org.springframework.beans.factory.support.AbstractBeanFactory.doResolveBeanClass(AbstractBeanFactory.java:1428) at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1372) ... 28 more 十月 17, 2019 9:24:39 上午 org.apache.catalina.core.StandardContext startInternal 严重: Error listenerStart 十月 17, 2019 9:24:39 上午 org.apache.catalina.core.StandardContext startInternal 严重: Context [] startup failed due to previous errors 十月 17, 2019 9:24:39 上午 org.apache.catalina.core.ApplicationContext log 信息: Closing Spring root WebApplicationContext 十月 17, 2019 9:24:39 上午 org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc 严重: The web application [] registered the JDBC driver [com.mysql.cj.jdbc.Driver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered. 十月 17, 2019 9:24:39 上午 org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc 严重: The web application [] registered the JDBC driver [com.alibaba.druid.proxy.DruidDriver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered. 十月 17, 2019 9:24:39 上午 org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc 严重: The web application [] registered the JDBC driver [com.alibaba.druid.mock.MockDriver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered. 十月 17, 2019 9:24:39 上午 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads 严重: The web application [] appears to have started a thread named [mysql-cj-abandoned-connection-cleanup] but has failed to stop it. This is very likely to create a memory leak. 十月 17, 2019 9:24:39 上午 org.apache.coyote.AbstractProtocol start 信息: Starting ProtocolHandler ["http-bio-9101"] 十月 17, 2019 9:24:44 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:24:49 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:24:54 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:24:59 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:04 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:09 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:14 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:19 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:24 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:29 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:34 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:39 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:44 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:49 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:54 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:25:59 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:26:04 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:26:09 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:26:14 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:26:19 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:26:24 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. 十月 17, 2019 9:26:29 上午 org.apache.catalina.loader.WebappClassLoader findResourceInternal 信息: Illegal access: this web application instance has been stopped already. Could not load . The eventual following stack trace is caused by an error thrown for debugging purposes as well as to attempt to terminate the thread which caused the illegal access, and has no functional impact. ``` ```

我的myeclipse中做j2ee项目加载了mysql报错了

package com.yyc.controller; import java.io.IOException; import java.io.PrintWriter; import java.sql.*; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class LoginC1Servlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("utf-8"); //response.setContentType("text/html;charset=UTF-8"); //PrintWriter out = response.getWriter(); String id =request.getParameter("id"); String password=request.getParameter("password"); //从数据库中获取验证 Connection con=null; ResultSet rs=null; PreparedStatement ps=null; try{ //1.加载驱动 Class.forName("mysql.jdbc.Driver"); //2.得到链接 con = DriverManager.getConnection("jdbc:mysql://localhost:3306/itat_shop", "root", "chuan080702"); //3.preparedStatement ps=con.prepareStatement("select *from users where id=? and passwd=?"); //给?号赋值 ps.setObject(1,id); ps.setObject(2,password); //4.执行操作 rs=ps.executeQuery(); //5.根据结果做相应的处理 if(rs.next()){ //说明该用户合法 request.getRequestDispatcher("/MainFrame").forward(request, response); }else{ request.setAttribute("err", "用户id或密码错误!!!"); request.getRequestDispatcher("/LoginServlet").forward(request, response); } }catch(Exception e){ e.printStackTrace(); }finally{ //关闭资源 if(rs!=null){ try{ rs.close(); }catch(Exception e){ e.printStackTrace(); } rs=null; } if(ps!=null){ try{ ps.close(); }catch(Exception e){ e.printStackTrace(); } ps=null; }if(con!=null){ } try{ con.close(); }catch(Exception e){ e.printStackTrace(); } con=null; } /* //检查是否接受数据 //这里我们先简单验证 if("yangyongchuan".equals(username)&&"123".equals(password)){ //跳转到下一个页面[servlet 提供了两种Sendredirect跳转forward 转发] response.sendRedirect("/UserManager/MainFrame?uname="+username); }else{ //跳回 response.sendRedirect("/UserManager/LoginServlet"); } **/ } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { this.doGet(request, response); } } 信息: Server startup in 14390 ms java.lang.ClassNotFoundException: mysql.jdbc.Driver at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1680) at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526) at java.lang.Class.forName0(Native Method) at java.lang.Class.forName(Class.java:190) at com.yyc.controller.LoginC1Servlet.doGet(LoginC1Servlet.java:30) at com.yyc.controller.LoginC1Servlet.doPost(LoginC1Servlet.java:112) at javax.servlet.http.HttpServlet.service(HttpServlet.java:643) at javax.servlet.http.HttpServlet.service(HttpServlet.java:723) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:879) at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:617) at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1778) at java.lang.Thread.run(Thread.java:744) java.lang.NullPointerException at com.yyc.controller.LoginC1Servlet.doGet(LoginC1Servlet.java:79) at com.yyc.controller.LoginC1Servlet.doPost(LoginC1Servlet.java:112) at javax.servlet.http.HttpServlet.service(HttpServlet.java:643) at javax.servlet.http.HttpServlet.service(HttpServlet.java:723) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:879) at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:617) at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1778) at java.lang.Thread.run(Thread.java:744)

Java web报错,Unknown database 'testdb'

在运行jsp插入数据一直报错Unknown database 'testdb',Mysql是8.0的,试过其他办法都没有用。页面报500错误 <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>添加图书信息</title> </head> <body> <p>请输入图书信息</p> ${message}<br> <form action="addBook" method="post"> 书号:<input type="text" name="isbn"/><br> 书名:<input type="text" name="title"/><br> 价格:<input type="text" name="price"/><br> <input type="submit" value="确定"/><input type="reset" value="重置"/> </form> </body> </html> ``` ``` ``` package servlet; import java.io.IOException; import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import com.mysql.jdbc.Statement; @WebServlet("/addBook") public class BookServlet extends HttpServlet { private static final long serialVersionUID = 1L; Connection dbconn = null; @Override public void init() { try { Class.forName("com.mysql.cj.jdbc.Driver"); dbconn = DriverManager.getConnection( "jdbc:mysql://127.0.0.1:3306/testDB?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT&allowPublicKeyRetrieval=true", "root", "123456"); } catch (ClassNotFoundException el) { getServletContext().log("驱动程序类找不到"); } catch (SQLException e2) { System.out.println(e2); } } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("utf-8"); String isbn = request.getParameter("isbn"); String title = request.getParameter("title"); float price = Float.parseFloat(request.getParameter("price")); String message = ""; try { String sql = "INSERT INTO books (isbn,title,price) VALUES(?,?,?)"; PreparedStatement pstmt = dbconn.prepareStatement(sql); pstmt.setString(1, isbn); pstmt.setString(2, title); pstmt.setFloat(3, price); int num = pstmt.executeUpdate(); if (num == 1) { message = "插入记录成功"; } else { message = "插入记录失败"; } request.setAttribute("message", message); request.getRequestDispatcher("jsp/add-book.jsp").forward(request, response); } catch (SQLException e) { message = e.getMessage(); request.setAttribute("message", message); request.getRequestDispatcher("jsp/add-book.jsp").forward(request, response); } } @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { // TODO Auto-generated method stub super.doGet(req, resp); } } ``` ``` <?xml version="1.0" encoding="UTF-8"?> <Context reloadable = "true"> <Resource name="jdbc/testDB" type="javax.sql.DataSource" maxActive="4" maxIdle="2" username="root" password="123456" maxwait="5000" driverClassName="com.mysql.cj.jdbc.Driver" url="jdbc:mysql://127.0.0.1:3306/testdb?useSLL=true&amp;useUnicode=true&amp;allowPublicKeyRetrieval=true;characterEncoding=utf-8" /> </Context> ``

JAVAEE:JSP传值给数据库,测试信息进行登录

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已经连续五年参加大厂校招、社招的技术面试工作,简历看的不下于万份 这篇文章会用实例告诉你,什么是差的程序员简历! 疫情快要结束了,各个公司也都开始春招了,作为即将红遍大江南北的新晋UP主,那当然要为小伙伴们做点事(手动狗头)。 就在公众号里公开征简历,义务帮大家看,并一一点评。《启舰:春招在即,义务帮大家看看简历吧》 一石激起千层浪,三天收到两百多封简历。 花光了两个星期的所有空闲时...

《经典算法案例》01-08:如何使用质数设计扫雷(Minesweeper)游戏

我们都玩过Windows操作系统中的经典游戏扫雷(Minesweeper),如果把质数当作一颗雷,那么,表格中红色的数字哪些是雷(质数)?您能找出多少个呢?文中用列表的方式罗列了10000以内的自然数、质数(素数),6的倍数等,方便大家观察质数的分布规律及特性,以便对算法求解有指导意义。另外,判断质数是初学算法,理解算法重要性的一个非常好的案例。

《Oracle Java SE编程自学与面试指南》最佳学习路线图(2020最新版)

正确选择比瞎努力更重要!

Java岗开发3年,公司临时抽查算法,离职后这几题我记一辈子

前几天我们公司做了一件蠢事,非常非常愚蠢的事情。我原以为从学校出来之后,除了找工作有测试外,不会有任何与考试有关的事儿。 但是,天有不测风云,公司技术总监、人事总监两位大佬突然降临到我们事业线,叫上我老大,给我们组织了一场别开生面的“考试”。 那是一个风和日丽的下午,我翘着二郎腿,左手端着一杯卡布奇诺,右手抓着我的罗技鼠标,滚动着轮轴,穿梭在头条热点之间。 “淡黄的长裙~蓬松的头发...

面试官:你连SSO都不懂,就别来面试了

大厂竟然要考我SSO,卧槽。

终于,月薪过5万了!

来看几个问题想不想月薪超过5万?想不想进入公司架构组?想不想成为项目组的负责人?想不想成为spring的高手,超越99%的对手?那么本文内容是你必须要掌握的。本文主要详解bean的生命...

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