当TomCat启动后能不能更改Spring的数据库连接，如何改

当TomCat启动后能不能更改Spring的数据库连接，如何改？ [b]问题补充：[/b] 问题描述： 当进入系统前会有一个数据库连接选择，其中主要是改变连接的用户名和密码，但每次服务一启动，就自动加载了applicationContext.xml，不论你怎么改用户名，都只是前一次的，如何做才能达到我想要的？ [b]问题补充：[/b] 我用的是spring+jpa+flex [b]问题补充：[/b] 手动加载spring的配置文件： 具体如何实现？ [b]问题补充：[/b] ContextLoader contextLoader = new ContextLoader(); contextLoader.initWebApplicationContext(request.getSession().getServletContext()); 找不到applicationContext.xml，它给的路径是/WEB-INF/applicationContext.xml，而我的是在/WEB-INF/classes/applicationContext.xml下的，怎样改啊？ [b]问题补充：[/b] 但是它出错啦，当刷新页面，切换数据库时： Cannot initialize context because there is already a root application context present - check whether you have multiple ContextLoader* definitions in your web.xml

spring boot 集成activiti如何能在启动时不配置数据库参数

<?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.9.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.example</groupId> <artifactId>leave</artifactId> <version>0.0.1-SNAPSHOT</version> <name>leave</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.activiti</groupId> <artifactId>activiti-spring-boot-starter-basic</artifactId> <version>6.0.0</version> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-tomcat</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web-services</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> ------上面是spring boot 的pom.xml 在application.properties配置好数据库参数就可以正常运行。我的想法是在程序启动的时候不连接数据库，在程序运行的过程中按需连接到数据库，但我删除了数据可参数的时候就报错了！！！信息如下： Description: Cannot determine embedded database driver class for database type NONE Action: If you want an embedded database please put a supported one on the classpath. If you have database settings to be loaded from a particular profile you may need to active it (no profiles are currently active). 在网上找到的解决方案是添加注解(分别如下尝试都出错)： 1.------------------------- @EnableAutoConfiguration(exclude={DataSourceAutoConfiguration.class,HibernateJpaAutoConfiguration.class}) @SpringBootApplication 2.--------------------------------------- @SpringBootApplication(exclude={DataSourceAutoConfiguration.class}) 3.------------------------------------ @SpringBootApplication(exclude = {DataSourceAutoConfiguration.class,DataSourceTransactionManagerAutoConfiguration.class,HibernateJpaAutoConfiguration.class}) 错误信息如下： Description: Parameter 0 of method springProcessEngineConfiguration in org.activiti.spring.boot.JpaProcessEngineAutoConfiguration$JpaConfiguration required a bean of type 'javax.sql.DataSource' that could not be found. - Bean method 'dataSource' not loaded because @ConditionalOnProperty (spring.datasource.jndi-name) did not find property 'jndi-name' - Bean method 'dataSource' not loaded because @ConditionalOnBean (types: org.springframework.boot.jta.XADataSourceWrapper; SearchStrategy: all) did not find any beans Action: Consider revisiting the conditions above or defining a bean of type 'javax.sql.DataSource' in your configuration

spring 连接数据库的问题

<p><span style=""><strong>用的spring+hibernate,那位达人能帮忙解决下,感激不尽.<br />web.xml里:</strong></span><br />....<br />&lt;context-param&gt;<br />  &lt;param-name&gt;contextConfigLocation&lt;/param-name&gt;<br />  &lt;param-value&gt;<br />   /WEB-INF/applicationContext.xml<br />  &lt;/param-value&gt;<br /> &lt;/context-param&gt;<br /> &lt;servlet&gt;<br />    &lt;servlet-name&gt;context&lt;/servlet-name&gt;<br />    &lt;servlet-class&gt;org.springframework.web.context.ContextLoaderServlet&lt;/servlet-class&gt;<br />    &lt;load-on-startup&gt;1&lt;/load-on-startup&gt;<br />&lt;/servlet&gt;<br /><span style="">....</span></p> <p><span style=""><strong>applicationContext.xml里:</strong></span><br />....<br />&lt;bean id="dataSource" &lt;br=""&gt;  class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"&gt;<br />  &lt;property name="driverClassName" &lt;br=""&gt;   value="com.mysql.jdbc.Driver"&gt;<br />  &lt;/property&gt;<br />  &lt;property name="url" &lt;br=""&gt;   value="jdbc:mysql://localhost:3306/test"&gt;<br />  &lt;/property&gt;<br />  &lt;property name="username" value="root"&gt;&lt;/property&gt;<br />  &lt;property name="password" value="root"&gt;&lt;/property&gt;<br /> &lt;/bean&gt;<br /> &lt;bean id="sessionFactory" &lt;br=""&gt;  class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"&gt;<br />  &lt;property name="dataSource"&gt;<br />   &lt;ref bean="dataSource"&gt;<br />  &lt;/property&gt;<br />  &lt;property name="hibernateProperties"&gt;<br />   &lt;props&gt;<br />    &lt;prop key="hibernate.dialect"&gt;<br />     org.hibernate.dialect.MySQLDialect<br />    &lt;/prop&gt;<br />   &lt;/props&gt;<br />  &lt;/property&gt;<br />  &lt;property name="mappingResources"&gt;<br />   &lt;list&gt;<br />    &lt;value&gt;com/test/vo/User.hbm.xml&lt;/value&gt;<br />  &lt;/property&gt;</p> <p>&lt;/bean&gt;</p> <p>&lt;bean id="transactionManager" &lt;br=""&gt;   class="org.springframework.orm.hibernate3.HibernateTransactionManager"&gt;<br />       &lt;property name="sessionFactory"&gt;<br />           &lt;ref local="sessionFactory"&gt;<br />       &lt;/property&gt;<br />  &lt;/bean&gt;<br />  &lt;bean id="userDAOProxy" &lt;br=""&gt;   class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean"&gt;<br />     &lt;property name="transactionManager"&gt;<br />         &lt;ref bean="transactionManager"&gt;<br />     &lt;/property&gt;<br />     &lt;property name="target"&gt;<br />         &lt;ref local="userDAO"&gt;<br />     &lt;/property&gt;<br />     &lt;property name="transactionAttributes"&gt;<br />         &lt;props&gt;<br />            &lt;prop key="save*"&gt;PROPAGATION_REQUIRED &lt;/prop&gt; <br />            &lt;prop key="update*"&gt;PROPAGATION_REQUIRED &lt;/prop&gt; <br />            &lt;prop key="delete*"&gt;PROPAGATION_REQUIRED &lt;/prop&gt; <br />            &lt;prop key="find*"&gt;PROPAGATION_REQUIRED,readOnly &lt;/prop&gt;<br />         &lt;/props&gt;<br />     &lt;/property&gt;<br />   &lt;/bean&gt;</p> <p> &lt;bean id="userDAO" class="com.test.dao.Impl.UserDAOImpl"&gt;<br />  &lt;property name="sessionFactory"&gt;<br />   &lt;ref bean="sessionFactory"&gt;<br />  &lt;/property&gt;<br /> &lt;/bean&gt;<br />....</p> <p> </p> <p><span style=""><strong>DAO里:</strong></span></p> <p><strong><span style="">...</span></strong></p> <p><br />public class UserDAOImpl extends HibernateDaoSupport implements UserDAO{<br /> private static final Log log = LogFactory.getLog(UserDAOImpl.class);<br /> private String hql = "from user u where u.name = ?";<br /> private boolean bo= false;<br /> <br /> protected void initDao() {<br />  // do nothing<br /> }</p> <p> public boolean save(User user) {<br />  try {<br />   this.getHibernateTemplate().save(user);//<span style=""><strong>执行到这里出错,User对象里的name和passwd不是空的</strong></span>.<br />   this.getHibernateTemplate().flush();//<span style=""><strong>getHibernateTemplate()调用的各种操作都出现这样的错误.</strong></span><br />   bo = true;<br />  } catch (RuntimeException re) {<br />   throw re;<br />  }<br />  return bo;<br /> }</p> <p>}</p> <p>.......</p> <p><span style=""><strong>出现的错误提示如下:</strong></span></p> <p>2008-8-22 13:18:34 org.apache.catalina.core.StandardWrapperValve invoke<br />严重: Servlet.service() for servlet regedit threw exception<br />java.lang.NullPointerException<br /> at com.test.dao.Impl.UserDAOImpl.save(UserDAOImpl.java:41)<br /> at com.test.service.Impl.RegeditImpl.save(RegeditImpl.java:27)<br /> at com.test.action.RegeditController.doPost(RegeditController.java:32)<br /> at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)<br /> at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)<br /> at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)<br /> at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)<br /> at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:230)<br /> at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)<br /> at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)<br /> at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104)<br /> at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)<br /> at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:261)<br /> at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:844)<br /> at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:581)<br /> at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)<br /> at java.lang.Thread.run(Thread.java:674)</p> <p> </p><br /><strong>问题补充：</strong><br />我把spring 配置文件里的标签随便删几个,让不对应,或把dataSource改了,竟然还是提示这样的错误!!! <br />在web.xml里使用listener,启动tomcat时就出错. <br />郁闷了啊!<br /><strong>问题补充：</strong><br />怎么测试spring hibernate 连接数据库了?

使用springcloud 和 连接池 连接orcale数据库报错，折磨一天了，请大佬解救，启动都正常的

数据库使用PLsql可以连接上，ping数据库主机也是通的。找了一天问题了，求大佬解救一下。基本可以排除数据库问题，现在迷了一天了，想早点下班。。。 报错信息： 2018-12-28 17:00:06.350 ERROR 21560 --- [http-nio-9661-exec-2] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception org.springframework.transaction.CannotCreateTransactionException: Could not open JDBC Connection for transaction; nested exception is java.lang.NullPointerException at org.springframework.jdbc.datasource.DataSourceTransactionManager.doBegin(DataSourceTransactionManager.java:289) ~[spring-jdbc-4.3.12.RELEASE.jar:4.3.12.RELEASE] at org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:373) ~[spring-tx-4.3.12.RELEASE.jar:4.3.12.RELEASE] at org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:447) ~[spring-tx-4.3.12.RELEASE.jar:4.3.12.RELEASE] at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:277) ~[spring-tx-4.3.12.RELEASE.jar:4.3.12.RELEASE] at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96) ~[spring-tx-4.3.12.RELEASE.jar:4.3.12.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.3.11.RELEASE.jar:4.3.11.RELEASE] at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) ~[spring-aop-4.3.11.RELEASE.jar:4.3.11.RELEASE] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) ~[spring-aop-4.3.11.RELEASE.jar:4.3.11.RELEASE] at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:673) ~[spring-aop-4.3.11.RELEASE.jar:4.3.11.RELEASE] at grp.pt.common.bs.CacheService$$EnhancerBySpringCGLIB$$14ccc726.putMap(<generated>) ~[grp-util-com-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT] at grp.pt.util.PublicSessionUtil.createSession(PublicSessionUtil.java:118) ~[grp-util-com-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT] at grp.pt.util.PublicSessionUtil.initSessionInfo(PublicSessionUtil.java:39) ~[grp-util-com-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT] at grp.util.session.UserSessionFilter.doFilter(UserSessionFilter.java:41) ~[grp-util-com-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.23.jar:8.5.23] at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-4.3.11.RELEASE.jar:4.3.11.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.11.RELEASE.jar:4.3.11.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.23.jar:8.5.23] at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:108) ~[spring-web-4.3.11.RELEASE.jar:4.3.11.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.11.RELEASE.jar:4.3.11.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.23.jar:8.5.23] at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) ~[spring-web-4.3.11.RELEASE.jar:4.3.11.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.11.RELEASE.jar:4.3.11.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.23.jar:8.5.23] at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) ~[spring-web-4.3.11.RELEASE.jar:4.3.11.RELEASE] at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.11.RELEASE.jar:4.3.11.RELEASE] at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) ~[tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478) [tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) [tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) [tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) [tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459) [tomcat-embed-core-8.5.23.jar:8.5.23] at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.23.jar:8.5.23] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_144] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_144] at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.23.jar:8.5.23] at java.lang.Thread.run(Thread.java:748) [na:1.8.0_144] Caused by: java.lang.NullPointerException: null at grp.pt.util.PublicSessionUtil.getDataSourceBeanKey(PublicSessionUtil.java:138) ~[grp-util-com-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT] at grp.pt.database.DynamicDataSource.determineCurrentLookupKey(DynamicDataSource.java:21) ~[grp-database-0.0.1-SNAPSHOT.jar:0.0.1-SNAPSHOT] at org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource.determineTargetDataSource(AbstractRoutingDataSource.java:196) ~[spring-jdbc-4.3.12.RELEASE.jar:4.3.12.RELEASE] at org.springframework.jdbc.datasource.lookup.AbstractRoutingDataSource.getConnection(AbstractRoutingDataSource.java:164) ~[spring-jdbc-4.3.12.RELEASE.jar:4.3.12.RELEASE] at org.springframework.jdbc.datasource.DataSourceTransactionManager.doBegin(DataSourceTransactionManager.java:246) ~[spring-jdbc-4.3.12.RELEASE.jar:4.3.12.RELEASE] ... 46 common frames omitted yml数据库配置内容 ``` dynamicdata: #系统运行模式[Develop, Product] mode: Develop #默认数据源 defaultKey: admdiv jndiName: data-sources: #数据源名: admdiv_年度_区划code admdiv: driverClassName: oracle.jdbc.driver.OracleDriver #url: jdbc:oracle:thin:@localhost:1521:orcl #driverClassName: com.mysql.jdbc.Driver #连接URL，协议+地址+Scheme #url: jdbc:mysql://localhost:3306/gap_ah?useUnicode=true&characterEncoding=utf8&useSSL=false username: yszx2018 #密码 password: a #数据库连接池配置样例 url: jdbc:oracle:thin:@localhost:1521:orcl #连接池的最大连接数，-1为无限制 maxActive: 8 #最大空闲连接数，-1为无限制。注：如果是高负载系统，此值过低时可能会出现连接关闭的同时会打开新连接，连接池失效 maxIdle: 8 #在连接池满的情况下最长等待时间（毫秒），如果超时则抛异常，-1为一直等待 maxWait: -1 #初始连接数 initialSize: 8 #自动回收超时连接 removeAbandoned: true #自动回收超时时间(以秒数为单位) removeAbandonedTimeout: 3600000 #是否要进行检测 testWhileIdle: true #进行检测一个连接是有效的SQL语句，比如oracle是select 1 from dual 而 mysql是 select 1 validationQuery: select 1 from dual #每隔多少时间检测一次，比如每半小时检测一次，总不能总是检测，这会对性能产生影响 timeBetweenEvictionRunsMillis: 180000 #每次检测时，需要检测多少个数据连接，一般设置为与最大连接数一样，这样就可以检测完所有的连接 numTestsPerEvictionRun: 8 #一个数据库连接连接多少时间之外，我们认为其应该不再适用了(可能下一次就会失效了)，应该移除并重新建立连接了 minEvictableIdleTimeMillis: 3600000 ```

在系统访问高峰期出现无法获取数据库连接的异常

最近遇到一个棘手的问题,请教各位能否查明报出异常的原因： 1：正常情况下系统运行没有问题，但是系统访问高峰情况下会出现，日志如下，这段日志出现一段时间之后，应用就会假死，持续1分钟左右之后恢复。 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 : javax.resource.ResourceException: IJ000453: Unable to get managed connection for java:jboss/datasources/PnrDS The error may exist in com/huifu/muser/common/dal/dao/MerUsrMapMapper.xml The error may involve com.huifu.muser.common.dal.dao.MerUsrMapMapper.queryMerUsrMap The error occurred while executing a query Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is java.sql.SQLException: javax.resource.ResourceE xception: IJ000453: Unable to get managed connection for java:jboss/datasources/PnrDS at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:73) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:365) at com.sun.proxy.$Proxy157.selectList(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:195) at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:124) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:90) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:40) at com.sun.proxy.$Proxy158.queryMerUsrMap(Unknown Source) at com.huifu.muser.service.core.cash.impl.CashReqServiceImpl.checkMerUsrMap(CashReqServiceImpl.java:267) at com.huifu.muser.biz.cash.impl.CashReqManager2Impl.cashConfirmReq(CashReqManager2Impl.java:211) at com.huifu.muser.webapp.controller.cash.CashController.cashConfirm2(CashController.java:200) at sun.reflect.GeneratedMethodAccessor2127.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176) at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:426) at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:414) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:790) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:719) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:644) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:560) at javax.servlet.http.HttpServlet.service(HttpServlet.java:754) at javax.servlet.http.HttpServlet.service(HttpServlet.java:847) 2：我的应用框架是 spring3.0.5+mybatis3.1.1+JBoss7.1+oracle11+jdk1.6 3：负载均衡 netscaler,两台虚拟机，四核，内存8G,jvm启动参数配置如下： -XX:+UseCompressedOops -XX:+TieredCompilation -Xms4096m -Xmx4096m -Xmn1024m -XX:PermSize=256M -XX:MaxPermSize=512M -Djava.net.preferIPv4Stack=true -Dorg.jboss.resolver.warning=true -Dsun.rmi.dgc.client.gcInterval=3600000 -Dsun.rmi.dgc.server.gcInterval=3600000 -XX:SurvivorRatio=8 -XX:+UseParNewGC -XX:+UseConcMarkSweepGC -XX:+CMSParallelRemarkEnabled -XX:+UseCMSCompactAtFullCollection -XX:CMSFullGCsBeforeCompaction=0 -XX:+UseCMSInitiatingOccupancyOnly -XX:CMSInitiatingOccupancyFraction=70 -Xnoclassgc -XX:+CMSClassUnloadingEnabled 4：我的数据库链接池是配置在jboss的配置文件standalone-ha.xml中，连接池配置为18-300，高峰期能达到300，即应用确实与数据库建立300链接，但是活跃链接在15左右，配置如下 

在线等!!!linux服务器连接mysql5.7数据库报错 Could not get JDBC Connection; nested exception is com.alibaba.druid.pool.GetConnectionTimeoutException

以下是服务器上的报错代码  ``` >org.springframework.web.util.NestedServletException: 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 com.alibaba.druid.pool.GetConnectionTimeoutException: wait millis 1000, active 0, maxActive 500, creating 1 ``` 问题就是出在这里. 1,本地项目正常启动,无任何报错,数据库连接正常（使用的都是linux上面的数据库）.  2,数据库工具使用无任何问题  3,下面放出jdbc配置文件和spring配置文件 ``` jdbc.driverClassName=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql://..XXXXXX.:/XXXXXX?useUnicode=true&characterEncoding=UTF-8&useSSL=false jdbc.username=xxxx jdbc.password=xxxxx jdbc.filters=stat jdbc.maxActive=500 jdbc.initialSize=1 jdbc.maxWait=1000 jdbc.minIdle=10 jdbc.maxIdle=15 jdbc.timeBetweenEvictionRunsMillis=60000 jdbc.minEvictableIdleTimeMillis=300000 jdbc.validationQuery=SELECT 'x' jdbc.testWhileIdle=true jdbc.testOnBorrow=false jdbc.testOnReturn=false jdbc.maxOpenPreparedStatements=20 jdbc.removeAbandoned=true jdbc.removeAbandonedTimeout=180 jdbc.logAbandoned=true ``` spring 配置 ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd"> <!-- 扫描service包下所有使用注解的类型 --> <context:component-scan base-package="com.yoFish.service"/> <!-- 配置数据库相关参数properties的属性：${url} --> <context:property-placeholder location="classpath:jdbc.properties"/> <!-- 阿里 druid 数据库连接池 --> <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" destroy-method="close"> <!-- 数据库基本信息配置 --> <property name="driverClassName" value="${jdbc.driverClassName}"/> <property name="url" value="${jdbc.url}"/> <property name="username" value="${jdbc.username}"/> <property name="password" value="${jdbc.password}"/> <property name="filters" value="${jdbc.filters}"/> <!-- 最大并发连接数 --> <property name="maxActive" value="${jdbc.maxActive}"/> <!-- 初始化连接数量 --> <property name="initialSize" value="${jdbc.initialSize}"/> <!-- 配置获取连接等待超时的时间 --> <property name="maxWait" value="${jdbc.maxWait}"/> <!-- 最小空闲连接数 --> <property name="minIdle" value="${jdbc.minIdle}"/> <!-- 最大空闲连接数 --> <property name="maxIdle" value="${jdbc.maxIdle}"/> <!-- 配置间隔多久才进行一次检测，检测需要关闭的空闲连接，单位是毫秒 --> <property name="timeBetweenEvictionRunsMillis" value="${jdbc.timeBetweenEvictionRunsMillis}"/> <!-- 配置一个连接在池中最小生存的时间，单位是毫秒 --> <property name="minEvictableIdleTimeMillis" value="${jdbc.minEvictableIdleTimeMillis}"/> <property name="validationQuery" value="${jdbc.validationQuery}"/> <property name="testWhileIdle" value="${jdbc.testWhileIdle}"/> <property name="testOnBorrow" value="${jdbc.testOnBorrow}"/> <property name="testOnReturn" value="${jdbc.testOnReturn}"/> <property name="maxOpenPreparedStatements" value="${jdbc.maxOpenPreparedStatements}"/> <!-- 超过时间限制是否回收 --> <property name="removeAbandoned" value="${jdbc.removeAbandoned}"/> <!-- 1800 秒，也就是 30 分钟 --> <property name="removeAbandonedTimeout" value="${jdbc.removeAbandonedTimeout}"/> <!-- 关闭 abanded 连接时输出错误日志 --> <property name="logAbandoned" value="${jdbc.logAbandoned}"/> </bean> <!-- 配置SqlSessionFactory对象 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 注入数据库连接池 --> <property name="dataSource" ref="dataSource"/> <!-- 扫描model包 使用别名 --> <property name="typeAliasesPackage" value="com.yoFish.model"/> <!-- 扫描sql配置文件:mapper需要的xml文件 --> <property name="mapperLocations" value="classpath:mapper/*.xml"/> </bean> <!-- 配置扫描Dao接口包，动态实现Dao接口，注入到spring容器中 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <!-- 注入sqlSessionFactory --> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/> <!-- 给出需要扫描Dao接口包 --> <property name="basePackage" value="com.yoFish.dao"/> </bean> <!-- 配置事务管理器 --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <!-- 注入数据库连接池 --> <property name="dataSource" ref="dataSource"/> </bean> <!-- 配置基于注解的声明式事务 --> <tx:annotation-driven transaction-manager="transactionManager"/> </beans> ``` 这个问题搞了很久了,主要就是不知道问题在哪,本地真的是没有任何问题,很多方式我也试过了.很头疼,求大佬帮忙解决

请教：Spring + Hibernate 无法将数据写入数据库?

Spring + Hibernate 无法将数据写入数据 **请教： 通过Junit单元测试Service可以将数据写入数据库；但部署访问却无法向数据库写入数据。** 1 环境： Spring 3.1.2 Hibernate 4.1.4 Jdk1.6 2 配置： 2.1 Web.xml <!-- Spring ApplicationContext配置文件的路径,可使用通配符,多个路径用,号分隔 此参数用于后面的Spring Context Loader --> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath*:/applicationContext.xml</param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <!--Dispathcer Servlet --> <servlet> <servlet-name>spring-mvc</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>/WEB-INF/spring-mvc.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <!-- Spring MVC Servlet 拦截.do结尾的请求--> <servlet-mapping> <servlet-name>spring-mvc</servlet-name> <url-pattern>*.do</url-pattern> </servlet-mapping> <!-- Filter 定义 --> <filter> <filter-name>encodingFilter</filter-name> <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class> <init-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </init-param> <init-param> <param-name>forceEncoding</param-name> <param-value>true</param-value> </init-param> </filter> <filter-mapping> <filter-name>encodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> <!--openSessionInView--> <filter> <filter-name>openSessionInView</filter-name> <filter-class>org.springframework.orm.hibernate4.support.OpenSessionInViewFilter</filter-class> <init-param> <param-name>sessionFactoryBeanName</param-name> <param-value>sessionFactory</param-value> </init-param> </filter> <filter-mapping> <filter-name>openSessionInView</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> 2.2 applicationContext.xml <!--扫描并自动装配 --> <context:annotation-config /> <context:component-scan base-package="com.sp" /> <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="locations"> <value>classpath:application.properties</value> </property> </bean> <!-- 数据源配置 --> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <!-- Connection Info --> <property name="driverClassName" value="${jdbc.driver}" /> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <!-- Connection Pooling Info --> <property name="maxActive" value="${dbcp.maxActive}" /> <property name="maxIdle" value="${dbcp.maxIdle}" /> <property name="defaultAutoCommit" value="false" /> <!-- 连接Idle一个小时后超时 --> <property name="timeBetweenEvictionRunsMillis" value="3600000" /> <property name="minEvictableIdleTimeMillis" value="3600000" /> </bean> <bean id="sessionFactory" class="org.springframework.orm.hibernate4.LocalSessionFactoryBean"> <property name="dataSource" ref="dataSource"></property> <property name="hibernateProperties"> <props> <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop> <prop key="hibernate.hbm2ddl.auto">update</prop> <prop key="hibernate.connection.autocommit">true</prop> <prop key="hibernate.current_session_context_class">org.springframework.orm.hibernate4.SpringSessionContext</prop> <prop key="hibernate.show_sql">true</prop> <prop key="hibernate.format_sql">true</prop> </props> </property> <property name="packagesToScan"> <list> <value>com.sp.dao</value> <value>com.sp.entity.dict</value> </list> </property> </bean> <bean id="transactionManager" class="org.springframework.orm.hibernate4.HibernateTransactionManager" abstract="false" lazy-init="default" autowire="default"> <property name="sessionFactory"><ref bean="sessionFactory" /></property> </bean> <!-- 事务管理配置 --> <!--<tx:annotation-driven transaction-manager="transactionManager"></tx:annotation-driven>--> <tx:advice id="txAdvice" transaction-manager="transactionManager"> <tx:attributes> <tx:method name="insert*" read-only="false" propagation="REQUIRED" /> <tx:method name="get*" read-only="false" propagation="REQUIRED" /> <tx:method name="add*" read-only="false" propagation="REQUIRED" /> <tx:method name="update*" read-only="false" propagation="REQUIRED" /> <tx:method name="delete*" read-only="false" propagation="REQUIRED" /> </tx:attributes> </tx:advice> <aop:config> <aop:advisor pointcut="execution(* com.sp.service.*.*(..))" advice-ref="txAdvice"/> </aop:config> </beans> 2.3 spring-mvc.xml <!-- 启动注解驱动的SpringMVC功能，注册请求URL和注解POJO类方法的映射 --> <mvc:annotation-driven /> <!-- 自动扫描且只扫描@Controller --> <context:component-scan base-package="com.sp.web" use-default-filters="false"> <context:include-filter type="annotation" expression="org.springframework.stereotype.Controller" /> </context:component-scan> <context:component-scan base-package="com.sp.dao.impl"></context:component-scan> <context:component-scan base-package="com.sp.service.impl"></context:component-scan> <mvc:default-servlet-handler /> <!-- 对模型视图名称的解析，在请求时模型视图名称添加后缀。定义JSP --> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/views/" /> <property name="suffix" value=".jsp" /> </bean> <!-- 支持上传文件 --> <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver" /> 2.4 hibernate.cfg.xml <property name="connection.driver_class">com.mysql.jdbc.Driver</property> <property name="connection.url">jdbc:mysql://localhost:3306/test</property> <property name="connection.username">root</property> <property name="connection.password">password</property> <!-- JDBC connection pool (use the built-in) --> <property name="connection.pool_size">1</property> <!-- SQL dialect <property name="dialect">org.hibernate.dialect.MySQLDialect</property> --> <!-- Enable Hibernate's automatic session context management --> <!-- <property name="current_session_context_class">thread</property> --> <!-- Disable the second-level cache --> <!-- <property name="cache.provider_class">org.hibernate.cache.internal.NoCacheProvider</property>--> <!-- Echo all executed SQL to stdout --> <property name="show_sql">true</property> <property name="format_sql">true</property> <!-- Drop and re-create the database schema on startup--> <property name="hbm2ddl.auto">update</property> <property name="javax.persistence.validation.mode">none</property> 3 代码： 3.1 Service层： @Component("userService") public class UserServiceImpl implements UserService{ @Autowired private UserDao userDao; @Autowired private FormValidator validator; @Override public String userLogin(UserModel user) { String password = userDao.userLogin(user); if(password.equals(user.getPassword())){ return "sucess"; }else{ return "false"; } } @Override public List<ProjectType> getAllProjectTypes(){ List<ProjectType> projectType = userDao.getAllProjectTypes(); return projectType; } @Override public String addProjectType(@ModelAttribute("newProjectType")ProjectType projectType,BindingResult result,SessionStatus status){ validator.validate(projectType, result); if(result.hasErrors()){ return "newProjectType"; } userDao.save(projectType); //status.setComplete(); return "redirect:showProjectTypes.do"; } //添加《项目类型》 @Override public String addProjectType(ProjectType projectType) { userDao.save(projectType); return "redirect:showProjectTypes.do"; } } 3.2 Control层 @Controller @RequestMapping(value = "/user") public class UserController { @Autowired private UserService userService; @Autowired private FormValidator validator; @RequestMapping(value = "/login",method=RequestMethod.POST) protected String handle(UserModel user,BindingResult result, Model model){ String flag = userService.userLogin(user); System.out.println("flag:" + flag); if ("sucess".equals(flag)){ return "sucess"; } return "test1"; } @RequestMapping(value = "/showProjectTypes") protected ModelAndView getAllProjectTypes(){ ModelAndView mav = new ModelAndView("showProjectTypes"); List<ProjectType> projectTypes = userService.getAllProjectTypes(); mav.addObject("SEARCH_PROJECTTYPE_RESULTS_KEY", projectTypes); return mav; } @RequestMapping(value = "/addProjectType",method=RequestMethod.GET) protected ModelAndView newProjectTypeForm(){ ModelAndView mav = new ModelAndView("newProjectType"); ProjectType projectType = new ProjectType(); mav.getModelMap().put("newProjectType", projectType); return mav; } @RequestMapping(value = "/saveProjectType",method=RequestMethod.POST) protected String addProjectType(@ModelAttribute("newProjectType")ProjectType projectType,BindingResult result,SessionStatus status){ //return userService.addProjectType(projectType, result, status); return userService.addProjectType(projectType); } } 3.3 DAO层 @Component("userDao") public class UserDaoImpl implements UserDao{ @Autowired private SessionFactory sessionFactory; public ProjectType getById(int id) { return (ProjectType) sessionFactory.getCurrentSession().get(ProjectType.class, id); } @Override public String userLogin(UserModel user) { return "123456"; } //获取数据 @Override @SuppressWarnings("unchecked") public List<ProjectType> getAllProjectTypes() { Criteria ceriteria = sessionFactory.getCurrentSession().createCriteria(ProjectType.class); return ceriteria.list(); } //新增数据； @Override // @Transactional(readOnly = true, propagation = Propagation.REQUIRED) public int save(ProjectType projectType) { System.out.println("save:---"); System.out.println(projectType.getIndex()); System.out.println(projectType.getProjectType()); System.out.println(projectType.getProjectTypeAbbr()); return (Integer) sessionFactory.getCurrentSession().save(projectType); } }

SpringBootWEB项目数据库连接关闭异常

1.问题描述 项目启动后，有30分钟一次的定时任务，在过一段时间后，就会抛出连接已关闭的异常，重启后又恢复正常 2.相关代码 多数据源配置：  ``` public class UfOau8userServiceImpl{ private final static Logger logger = LoggerFactory.getLogger(UfOau8userServiceImpl.class); @Autowired @Qualifier("OAJdbcTemplate") private JdbcTemplate oaJdbcTemplate; public Integer selectOAU8User(String cPersonCode){ String sql="select count(id) as idnum from uf_OAU8User where cPersonCode='"+cPersonCode+"'"; logger.info("查询OA数据库===="+sql); try{ Integer idnum =oaJdbcTemplate.queryForObject(sql,Integer.class); return idnum; }catch (Exception e){ logger.error(this.getClass().getName()+".selectOAU8User根据U8人员编号获取OA人员对应表数据异常="+e); logger.error(this.getClass().getName()+".selectOAU8User异常SQL="+sql); return -1; } } } ``` 3.报错信息 2018-12-06 15:00:00.178 [pool-1-thread-1] ERROR com.yt.service.oa.UfOau8userServiceImpl - com.yt.service.oa.UfOau8userServiceImpl.selectOAU8User根据U8人员编号获取OA人员对应表数据异常=org.springframework.jdbc.UncategorizedSQLException: StatementCallback; uncategorized SQLException for SQL [select count(id) as idnum from uf_OAU8User where cPersonCode='01027']; SQL state [null]; error code [0]; The connection is closed.; nested exception is com.microsoft.sqlserver.jdbc.SQLServerException: The connection is closed.

一个web项目,如何提供给外网使用？

如题：我用spring+mybatis+mysql写了一个web的项目，如何提供给外网使用， 已经申请好域名和空间。 只是不知道步骤， 1.怎么将自己的web项目发布到外网？ 2.数据库怎么连接？ 3.如何启动服务器？ PS:小白一个，有太多不明白的地方，还请大神概括下基本的步骤。

spring2.5,c3p0,hibernate3.2环境下 更新驱动后数据库连接报错

<p>环境运行一直没有问题，不过以前用的驱动不支持JDK1.6所以 下载了最新的驱动程序sqljdbc_4.0 用了其中的 sqljdbc4.jar</p> <p>因为数据库是windows验证所以WEB-INF\lib  下面也放了sqljdbc_auth.dll  文件</p> <p> </p> <p>applicationContext.mxl配置文件如下</p> <pre name="code" class="xml"> &lt;bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close"&gt; &lt;property name="driverClass" value="com.microsoft.sqlserver.jdbc.SQLServerDriver"&gt;&lt;/property&gt; &lt;property name="jdbcUrl" value="jdbc:sqlserver://192.168.100.56:1433;DatabaseName=RESEARCH;integratedSecurity=true;"&gt;&lt;/property&gt; &lt;property name="user" value=""&gt;&lt;/property&gt; &lt;property name="password" value=""&gt;&lt;/property&gt; &lt;property name="acquireRetryAttempts" value="1"&gt;&lt;/property&gt; &lt;property name="idleConnectionTestPeriod" value="100"&gt;&lt;/property&gt; &lt;!-- seconds --&gt; &lt;property name="maxPoolSize" value="15"&gt;&lt;/property&gt; &lt;property name="minPoolSize" value="5"&gt;&lt;/property&gt; &lt;!--JDBC的标准参数，用以控制数据源内加载的PreparedStatements数量。但由于预缓存的statements 属于单个connection而不是整个连接池。所以设置这个参数需要考虑到多方面的因素。 如果maxStatements与maxStatementsPerConnection均为0，则缓存被关闭。Default: 0--&gt; &lt;property name="maxStatements" value="5"&gt;&lt;/property&gt; &lt;!--maxStatementsPerConnection定义了连接池内单个连接所拥有的最大缓存statements数。Default: 0&gt; &lt;property name="maxStatementsPerConnection"&gt;&lt;/property--&gt; &lt;/bean&gt; </pre> <p> </p> <p> 启动tomcat时候报如下错误信息</p> <p> </p> <pre name="code" class="java">信息: Initializing Spring root WebApplicationContext Exception in thread "com.mchange.v2.async.ThreadPoolAsynchronousRunner$PoolThread-#1" java.lang.UnsatisfiedLinkError: com.microsoft.sqlserver.jdbc.AuthenticationJNI.SNISecGenClientContext([B[I[BI[B[I[ZLjava/lang/String;ILjava/lang/String;Ljava/lang/String;Ljava/util/logging/Logger;)I at com.microsoft.sqlserver.jdbc.AuthenticationJNI.SNISecGenClientContext(Native Method) at com.microsoft.sqlserver.jdbc.AuthenticationJNI.GenerateClientContext(AuthenticationJNI.java:80) at com.microsoft.sqlserver.jdbc.SQLServerConnection.sendLogon(SQLServerConnection.java:2691) at com.microsoft.sqlserver.jdbc.SQLServerConnection.logon(SQLServerConnection.java:2234) at com.microsoft.sqlserver.jdbc.SQLServerConnection.access$000(SQLServerConnection.java:41) at com.microsoft.sqlserver.jdbc.SQLServerConnection$LogonCommand.doExecute(SQLServerConnection.java:2220) at com.microsoft.sqlserver.jdbc.TDSCommand.execute(IOBuffer.java:5696) at com.microsoft.sqlserver.jdbc.SQLServerConnection.executeCommand(SQLServerConnection.java:1715) at com.microsoft.sqlserver.jdbc.SQLServerConnection.connectHelper(SQLServerConnection.java:1326) at com.microsoft.sqlserver.jdbc.SQLServerConnection.login(SQLServerConnection.java:991) at com.microsoft.sqlserver.jdbc.SQLServerConnection.connect(SQLServerConnection.java:827) at com.microsoft.sqlserver.jdbc.SQLServerDriver.connect(SQLServerDriver.java:1012) 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)</pre> <p> </p> <p>实在从日志中看不到什么有价值信息，所以还劳烦各位帮忙看看。</p> <p> </p>

springnvc+mybatis+C3P0连接池，一段时间数据库就崩溃了，求援~

云服务上有三个tomcat服务器，都启动一段时间后报异常，mysql数据库崩溃，求帮助，怎么配置都配置不行 applicationcontext中连接池配置 ``` <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <property name="driverClass" value="${jdbc.driver}" /> <property name="jdbcUrl" value="${jdbc.url}" /> <property name="user" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <!--连接池中保留的最小连接数。 --> <property name="minPoolSize" value="${minPoolSize}" /> <!--连接池中保留的最大连接数。Default: 15 --> <property name="maxPoolSize" value="${maxPoolSize}" /> <!--最大空闲时间,1800秒内未使用则连接被丢弃。若为0则永不丢弃。Default: 0 --> <property name="maxIdleTime" value="${maxIdleTime}" /> <!--当连接池中的连接耗尽的时候c3p0一次同时获取的连接数。Default: 3 --> <property name="acquireIncrement" value="${acquireIncrement}" /> <!--c3p0全局的PreparedStatements缓存的大小。如果maxStatements与maxStatementsPerConnection均为0，则缓存不生效，只要有一个不为0，则语句的缓存就能生效。如果默认值:0 --> <property name="maxStatements" value="${maxStatements}" /> <property name="initialPoolSize" value="${initialPoolSize}" /> <!--当连接池用完时客户端调用getConnection()后等待获取新连接的时间，如设为0则无限期等待。单位毫秒。Default: 0 --> <property name="checkoutTimeout" value="${checkoutTimeout}" /> <!--每60秒检查所有连接池中的空闲连接。Default: 0 --> <property name="idleConnectionTestPeriod" value="${idleConnectionTestPeriod}" /> <!--定义在从数据库获取新连接失败后重复尝试的次数。Default: 30 --> <property name="acquireRetryAttempts" value="${acquireRetryAttempts}" /> <property name="breakAfterAcquireFailure" value="${breakAfterAcquireFailure}" /> <property name="testConnectionOnCheckout" value="${testConnectionOnCheckout}" /> <property name="connectionCustomizerClassName" value="com.tanwuapp.util.handler.UTF8MB4ConnectionCustomizer" /> </bean> ``` ``` minPoolSize=10 <!--连接池中保留的最大连接数。Default: 15 --> maxPoolSize=40 <!--最大空闲时间,30秒内未使用则连接被丢弃。若为0则永不丢弃。Default: 0 --> maxIdleTime=30 <!--当连接池中的连接耗尽的时候c3p0一次同时获取的连接数。Default: 3 --> acquireIncrement=3 <!--c3p0全局的PreparedStatements缓存的大小。如果maxStatements与maxStatementsPerConnection均为0，则缓存不生效，只要有一个不为0，则语句的缓存就能生效。如果默认值: 0--> maxStatements=50 <!--maxStatementsPerConnection定义了连接池内单个连接所拥有的最大缓存statements数。默认值: 0 --> maxStatementsPerConnection=0 initialPoolSize=10 <!--当连接池用完时客户端调用getConnection()后等待获取新连接的时间，如设为0则无限期等待。单位毫秒。Default: 0 --> checkoutTimeout=10000 <!--每30秒检查所有连接池中的空闲连接。Default: 0 --> idleConnectionTestPeriod=30 <!--定义在从数据库获取新连接失败后重复尝试的次数。Default: 30 --> acquireRetryAttempts=30 breakAfterAcquireFailure=true testConnectionOnCheckout=false ``` 异常信息： ``` 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 org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failure The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.) ### The error may exist in file [/home/webapps/tomcat-1.2.1/tanwuapps/TanWuAppAPI_v1.2.1/WEB-INF/classes/com/tanwuapp/dao/mapper/BasBannerMapper.xml] ### The error may involve com.tanwuapp.dao.BasBannerDao.findAllInfo ### The error occurred while executing a query ### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Communications link failure The last packet sent successfully to the server was 0 milliseconds ago. The driver has not received any packets from the server.) at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:75) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:371) at com.sun.proxy.$Proxy9.selectList(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:198) at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:119) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:63) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:52) at com.sun.proxy.$Proxy42.findAllInfo(Unknown Source) at com.tanwuapp.service.impl.HomePageServiceImpl.getBannerList(HomePageServiceImpl.java:55) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:317) at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:198) at com.sun.proxy.$Proxy46.getBannerList(Unknown Source) at com.tanwuapp.controller.ProductSearchController.searchHomeBannerData(ProductSearchController.java:78) at com.tanwuapp.controller.ProductSearchController$$FastClassBySpringCGLIB$$1b828f00.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:700) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:150) at org.springframework.cache.interceptor.CacheInterceptor$1.invoke(CacheInterceptor.java:58) at org.springframework.cache.interceptor.CacheAspectSupport.execute(CacheAspectSupport.java:211) at org.springframework.cache.interceptor.CacheInterceptor.invoke(CacheInterceptor.java:66) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:172) at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:633) at com.tanwuapp.controller.ProductSearchController$$EnhancerBySpringCGLIB$$f6dc0725.searchHomeBannerData(<generated>) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:606) at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:219) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:132) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:745) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:686) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:953) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:855) at javax.servlet.http.HttpServlet.service(HttpServlet.java:650) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:829) at javax.servlet.http.HttpServlet.service(HttpServlet.java:731) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) 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:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:220) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:122) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:505) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:956) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:436) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1078) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:625) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:745) Caused by: org.apache.ibatis.exceptions.PersistenceException: ```

sqlSessionTemplate在tomcat启动时自动关闭

sqlSessionTemplate在tomcat启动时自动关闭 数据库连接没有问题 <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> <property name="configLocation" value="/WEB-INF/classes/resources/mybatis/mybatis-config.xml"></property> <!-- mapper扫描 --> <property name="mapperLocations" value="/WEB-INF/classes/resources/mybatis/*/*.xml"></property> </bean> <bean id="sqlSessionTemplate" class="org.mybatis.spring.SqlSessionTemplate"> <constructor-arg ref="sqlSessionFactory" /> <!-- <constructor-arg index="1" value="BATCH" /> --> </bean>

使用jdbc链接sqlserver 2008出现Could not get JDBC Connection，项目可以启动，但不能访问数据库

JDBC: mybatis: jar包没问题，可以正常连接2005的数据库，链接这个2008的就不行了，求助各位大神啊 报错代码：### The error occurred while executing a query ### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (I/O Error: Connection reset)] with root cause java.net.SocketException: Connection reset at java.net.SocketInputStream.read(SocketInputStream.java:209) at java.net.SocketInputStream.read(SocketInputStream.java:141) at java.io.DataInputStream.readFully(DataInputStream.java:195) at java.io.DataInputStream.readFully(DataInputStream.java:169) at net.sourceforge.jtds.jdbc.SharedSocket.readPacket(SharedSocket.java:842) at net.sourceforge.jtds.jdbc.SharedSocket.getNetPacket(SharedSocket.java:723) at net.sourceforge.jtds.jdbc.ResponseStream.getPacket(ResponseStream.java:466) at net.sourceforge.jtds.jdbc.ResponseStream.read(ResponseStream.java:103) at net.sourceforge.jtds.jdbc.TdsCore.nextToken(TdsCore.java:2206) at net.sourceforge.jtds.jdbc.TdsCore.login(TdsCore.java:603) at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:357) at net.sourceforge.jtds.jdbc.ConnectionJDBC3.<init>(ConnectionJDBC3.java:50) at net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:184) at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38) at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:582) at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1556) at org.apache.commons.dbcp.BasicDataSource.createPoolableConnectionFactory(BasicDataSource.java:1545) at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1388) at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044) 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:84) at org.mybatis.spring.transaction.SpringManagedTransaction.getConnection(SpringManagedTransaction.java:70) at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:336) at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:84) at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:62) at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:324) at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:83) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) 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$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:434) at com.sun.proxy.$Proxy17.selectList(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:231) at org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:137) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:75) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:59) at com.sun.proxy.$Proxy21.getproList(Unknown Source) at com.ytxd.service.DuplicateCheck.DuplicateCheckServiceImpl.getproList(DuplicateCheckServiceImpl.java:333) at com.ytxd.controller.DuplicateCheck.DuplicateCheck_Controller.GetList(DuplicateCheck_Controller.java:44) 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.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133) at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:97) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967) at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:872) at javax.servlet.http.HttpServlet.service(HttpServlet.java:648) at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) at javax.servlet.http.HttpServlet.service(HttpServlet.java:729) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:474) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79) at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349) at org.apache.coyote.http11.Http11Proce ssor.service(Http11Processor.java:783) at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:789) at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1437) at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:745)

Java的框架SSH整合的项目，项目启动时总是会报一个莫名其妙的错误？

Unable to load configuration. - [unknown location] Caused by: Unable to load configuration. - [unknown location] Caused by: Unable to load jar:file:/D:/mars-workspace/.metadata/.plugins/org.eclipse.wst.server.core/tmp0/wtpwebapps/vvvvvvvvvvv/WEB-INF/lib/struts2-spring-plugin-2.3.15.3.jar!/struts-plugin.xml - [unknown location] Caused by: Connection timed out: connect - [unknown location] Caused by: java.net.ConnectException: Connection timed out: connect 个人分析应该不是jar包冲突的问题，因为项目以前是可以正常运行的，以前出过一次这样的问题，但是放了两天之后再运行又可以正常运行了。。。。现在又出现了这样的问题，百度上有人说是因为查询次数太多导致无法查询，但是如代码所示，无论是在junit测试类中还是在spring容器刚刚初始化完成利用监听器立即查询所有权限的功能，均可以正常访问到数据库，所以应该也不是c3p0数据库连接池的原因，整的我现在也不知道到底是什么问题。。求指教。

Spring boot 2.1.3启动报错 java.lang.NoClassDefFoundError: org/springframework/util/unit/DataSize

Spring cloud + Spring boot 2.1.3 启动就报错 修改过spring 版本 还是不行  ``` <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.1.3.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.lskj</groupId> <artifactId>system-server</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>war</packaging> <name>system-server</name> <description>系统管理相关</description> <properties> <java.version>1.8</java.version> <spring-cloud.version>Greenwich.SR1</spring-cloud.version> <!--<spring.version>5.1.3</spring.version>--> </properties> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-client</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-eureka-server</artifactId> </dependency> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-netflix-ribbon</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> <!-- log4j --> <dependency> <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.17</version> </dependency> <!-- 数据库 --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.41</version> <scope>runtime</scope> </dependency> <!-- 数据库连接池 --> <dependency> <groupId>com.mchange</groupId> <artifactId>c3p0</artifactId> <version>0.9.5.2</version> </dependency> <!-- MyBatis --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>3.4.1</version> </dependency> <!-- mybatis/spring整合包 --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis-spring</artifactId> <version>1.3.1</version> </dependency> <!-- Spring --> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>4.3.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>4.3.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>4.3.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>4.3.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-tx</artifactId> <version>4.3.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>4.3.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>4.3.5.RELEASE</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-test</artifactId> <version>4.3.5.RELEASE</version> </dependency> <!-- db读写分离 --> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjrt</artifactId> <version>1.8.9</version> </dependency> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjweaver</artifactId> <version>1.8.9</version> </dependency> <!-- 定时器 --> <dependency> <groupId>org.quartz-scheduler</groupId> <artifactId>quartz</artifactId> <version>2.3.0</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>4.3.5.RELEASE</version> </dependency> <!-- redis --> <dependency> <groupId>redis.clients</groupId> <artifactId>jedis</artifactId> </dependency> <dependency> <groupId>org.springframework.data</groupId> <artifactId>spring-data-redis</artifactId> <version>1.6.1.RELEASE</version> </dependency> <!-- spring2.X集成redis所需common-pool2，使用jedis必须依赖它--> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-pool2</artifactId> <version>2.4.2</version> </dependency> <!-- mybatis分页插件依赖 --> <dependency> <groupId>com.github.pagehelper</groupId> <artifactId>pagehelper</artifactId> <version>4.0.0</version> </dependency> </dependencies> <dependencyManagement> <dependencies> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-dependencies</artifactId> <version>${spring-cloud.version}</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> <repositories> <repository> <id>spring-milestones</id> <name>Spring Milestones</name> <url>https://repo.spring.io/milestone</url> </repository> </repositories> </project> ```

spring 事务

在做spring和hibernate进行整合的时候，进行单元测试的时候，发现这样的异常 org.springframework.transaction.CannotCreateTransactionException: Could not open Hibernate Session for transaction; nested exception is org.hibernate.exception.GenericJDBCException: Cannot open connection 在控制台已经没有任何错误，不知道谁什么原因，在google了半天也没找到原因。谢谢大家！数据库采用的是mysql [b]问题补充：[/b] 我把xml发给大家看看。。非 常感谢啊 有点长 呵呵<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd"> <!-- <aop:aspectj-autoproxy/>基于注解方式进行aop开发 --> <context:annotation-config/><!-- 把注解注册到spring容器中 --> <!-- <context:component-scan base-package="bean"></context:component-scan>组件自动扫描 --> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="org.git.mm.mysql.Driver"/><!--驱动类 --> <property name="url" value="jdbc:mysql://localhost:3306/test" /><!--URL --> <property name="username" value="root"/><!--连接数据库用户名--> <property name="password" value="123456"/><!--连接数据库密码--> <property name="initialSize" value="1"/><!-- 连接池启动的初始值 --> <property name="maxActive" value="500"/><!-- 连接池的最大值 --> <property name="maxIdle" value="2"/><!-- 最大空闲值 ,经过高峰期后，恢复时候--> <property name="minIdle" value="2"/><!-- 最小空闲值--> </bean> <bean id="sessionFactory" class="org.springframework.orm.hibernate3.LocalSessionFactoryBean"><!-- 把hibernate session给spring管理 --> <property name="dataSource" ref="dataSource"/><!-- 匹配上面的数据源 --> <property name="mappingResources"> <list> <value>bean/Person.hbm.xml</value> </list> </property> <property name="hibernateProperties"> <value> hibernate.dialect=org.hibernate.dialect.MySQLDialect hibernate.hbm2ddl.auto=update hibernate.show_sql=true hibernate.format_sql=true </value> </property> </bean> <!-- 对hibernate的事物进行管理,对session的创建等都会提交到事物中 --> <bean id="txManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager"> <property name="sessionFactory" ref="sessionFactory"/> </bean> <bean id="personservice" class="bean.PersonService"></bean> <tx:annotation-driven transaction-manager="txManager"/><!-- 基于注解的方式申明事物 --> [b]问题补充：[/b] 因为我现在用的单元测试 还没有用到web容器 tomcat应该和tomcat没多大关系吧 呵呵！ [b]问题补充：[/b] 应该不是测试类的问题吧 测试类是这样写的 private static PersonServiceInter bean; @BeforeClass public static void setUpBeforeClass() throws Exception { ApplicationContext ac=new ClassPathXmlApplicationContext("springBean.xml"); bean=(PersonServiceInter)ac.getBean("[color=red]personservice[/color]"); } @Test public void testAdd() { System.out.print("sss"); bean.add(new Person("jiba")); } personservice的类代码 @Transactional//注解方式申明事务 public class PersonService implements PersonServiceInter { @Resource private SessionFactory sessionFactory; //用resource注解方式注入，一般都是这个方式 public void add(Person person){ sessionFactory.getCurrentSession().persist(person);//得到spring容器当前管理的session //方法执行前打开事物，执行完后就自动关闭 }

SSM链接mysql数据库问题Cannot create JDBC driver of class

八月 23, 2017 4:01:37 下午 org.apache.catalina.core.StandardWrapperValve invoke 严重: Servlet.service() for servlet [SpringMVC] in context with path [/liuyg] 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 org.apache.commons.dbcp.SQLNestedException: Cannot create JDBC driver of class 'com.mysql.jdbc.Driver' for connect URL 'jdbc:mysql:127.0.0.1:3306/tjfx' ### The error may exist in file [D:\tomcat - liuyg\tomcat-7.0.81\webapps\liuyg\WEB-INF\classes\com\Mapping\xt_userMapper.xml] ### The error may involve com.Dao.xt_userMapper.selectByPrimaryKey ### The error occurred while executing a query ### Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create JDBC driver of class 'com.mysql.jdbc.Driver' for connect URL 'jdbc:mysql:127.0.0.1:3306/tjfx'] with root cause java.sql.SQLException: No suitable driver 配置文件如下 jdbc.properties --------- jdbc.driver=com.mysql.jdbc.Driver jdbc.url=jdbc:mysql:127.0.0.1:3306/tjfx jdbc.username=root jdbc.password=root #定义初始连接数 jdbc.initialSize=0 #定义最大连接数 jdbc.maxActive=20 #定义最大空闲 jdbc.maxIdle=20 #定义最小空闲 jdbc.minIdle=1 #定义最长等待时间 jdbc.maxWait=600000 ---------- spring-mvc.xml ------------ <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <!-- 自动扫描该包，使SpringMVC认为包下用了@controller注解的类是控制器 --> <context:component-scan base-package="com" /> <!--避免IE执行AJAX时，返回JSON出现下载文件 --> <bean id="mappingJacksonHttpMessageConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"> <property name="supportedMediaTypes"> <list> <value>text/html;charset=UTF-8</value> </list> </property> </bean> <!-- 启动SpringMVC的注解功能，完成请求和注解POJO的映射 --> <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter"> <property name="messageConverters"> <list> <ref bean="mappingJacksonHttpMessageConverter" /> <!-- JSON转换器 --> </list> </property> </bean> <!-- 定义跳转的文件的前后缀 ，视图模式配置 --> <!-- <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> --> <!-- <property name="prefix" value="/WEB-INF/welcome/" /> --> <!-- <property name="suffix" value=".htm" /> --> <!-- </bean> --> <!-- 静态资源处理--> <mvc:default-servlet-handler/> <!-- 注解驱动--> <mvc:annotation-driven></mvc:annotation-driven> <!-- 配置文件上传，如果没有使用文件上传可以不用配置，当然如果不配，那么配置文件中也不必引入上传组件包 --> <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <!-- 默认编码 --> <property name="defaultEncoding" value="utf-8" /> <!-- 文件大小最大值 --> <property name="maxUploadSize" value="10485760000" /> <!-- 内存中的最大值 --> <property name="maxInMemorySize" value="40960" /> </bean> <!-- 视图模式配置,velocity配置文件--> <bean id="velocityConfig" class="org.springframework.web.servlet.view.velocity.VelocityConfigurer"> <property name="resourceLoaderPath" value="/welcome/" /> <property name="configLocation" value="classpath:velocity.properties" /> <property name="velocityProperties"> <props> <prop key="input.encoding">utf-8</prop> <prop key="output.encoding">utf-8</prop> </props> </property> </bean> <!-- 配置后缀 --> <bean id="velocityViewResolver" class="org.springframework.web.servlet.view.velocity.VelocityViewResolver"> <property name="suffix" value=".htm" /> <property name="contentType" value="text/html;charset=UTF-8"></property> </bean> <import resource="spring-mybatis.xml"/> </beans> --------------- spring-mybatis.xml ------------------ <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd"> <!-- 自动扫描 --> <context:component-scan base-package="com" /> <!-- 引入配置文件 --> <!-- 1.读取数据库配置文件 --> <context:property-placeholder location="classpath:jdbc.properties" system-properties-mode="NEVER"/> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="${jdbc.driver}" /> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <!-- 初始化连接大小 --> <property name="initialSize" value="${jdbc.initialSize}"></property> <!-- 连接池最大数量 --> <property name="maxActive" value="${jdbc.maxActive}"></property> <!-- 连接池最大空闲 --> <property name="maxIdle" value="${jdbc.maxIdle}"></property> <!-- 连接池最小空闲 --> <property name="minIdle" value="${jdbc.minIdle}"></property> <!-- 获取连接最大等待时间 --> <property name="maxWait" value="${jdbc.maxWait}"></property> </bean> <!-- spring和MyBatis完美整合，不需要mybatis的配置映射文件 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> <!-- 自动扫描mapping.xml文件 --> <property name="mapperLocations" value="classpath:com/Mapping/*.xml"></property> </bean> <!-- DAO接口所在包名，Spring会自动查找其下的类 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackage" value="com/Dao" /> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property> </bean> <!-- (事务管理)transaction manager, use JtaTransactionManager for global tx --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource" /> </bean> </beans> ----------------

Spring mvc 空指针错误

LoginController ``` @Controller public class LoginController { @RequestMapping("test") public void login() { LoginServiceImp loginService = new LoginServiceImp(); loginService.loadUserInfo(); } } ``` LoginServiceImp ``` public class LoginServiceImp implements ILoginService { LoginDaoImp loginDao = new LoginDaoImp(); /* * (non-Javadoc) * * @see * com.sani.service.ILoginService#loadUserInfo(com.sani.bean.UserInfoBean) */ public List loadUserInfo() { return loginDao.loadUserInfo(); } } ``` LoginDaoImp ``` public class LoginDaoImp extends BaseDao implements ILoginDao { /* * (non-Javadoc) * * @see com.sani.dao.ILoginDao#loadUserInfo() */ public List<UserInfoBean> loadUserInfo() { String sql = "select NOW();"; List tmpList = this.getJdbcTemplate().queryForList(sql); System.out.println(tmpList.size()); return tmpList; } } ``` BaseDao ``` public class BaseDao extends JdbcDaoSupport { Logger log = Logger.getLogger(this.getClass().getName()); } ``` web.xml ``` <?xml version="1.0" encoding="UTF-8"?> <web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <!-- 字符编码过滤器 --> <filter> <filter-name>encodingFilter</filter-name> <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class> <init-param> <param-name>encoding</param-name> <param-value>UTF-8</param-value> </init-param> <init-param> <param-name>forceEncoding</param-name> <param-value>true</param-value> </init-param> </filter> <context-param> <param-name>log4jConfigLocation</param-name> <param-value>classpath:log4j.properties</param-value> </context-param> <context-param> <param-name>log4jRefreshInterval</param-name> <param-value>60000</param-value> </context-param> <listener> <listener-class>org.springframework.web.util.Log4jConfigListener</listener-class> </listener> <!-- 应用上下文配置文件 --> <!-- Spring 容器加载 --> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring-db.xml</param-value> </context-param> <!-- 配置spring核心servlet --> <servlet> <servlet-name>spring</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:spring-servlet.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <!-- url-pattern配置为/，不带文件后缀，会造成其它静态文件(js，css等)不能访问。如配为*.do，则不影响静态文件的访问 --> <servlet-mapping> <servlet-name>spring</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <session-config> <session-timeout>30</session-timeout> </session-config> <!-- 欢迎页面 --> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> </web-app> ``` spring-servlet.xml ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.1.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.1.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.1.xsd"> <!-- 启动注解驱动的Spring MVC功能，注册请求url和注解POJO类方法的映射--> <mvc:annotation-driven /> <!-- 允许对静态资源文件的访问 --> <mvc:default-servlet-handler /> <!-- 启动包扫描功能，以便注册带有@Controller、@Service、@repository、@Component等注解的类成为spring的bean --> <context:component-scan base-package="com.sani.controller" /> <context:component-scan base-package="com.sani.service" /> <context:component-scan base-package="com.sani.dao" /> <!-- 对模型视图名称的解析，在请求时模型视图名称添加前后缀 --> <!-- jsp视图解析器 --> <bean id="jspViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" /> <property name="prefix" value="/WEB-INF/jsp/" /> <property name="suffix" value=".jsp" /> <property name="order" value="1" /> </bean> </beans> ``` spring-db.xml ``` <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:jaxws="http://cxf.apache.org/jaxws" xmlns:task="http://www.springframework.org/schema/task" xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-3.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd http://cxf.apache.org/jaxws http://cxf.apache.org/schemas/jaxws.xsd" default-autowire="byName"> <!-- <context:property-placeholder location="classpath:jdbc.properties" /> --> <!-- 配置数据源 --> <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" destroy-method="close" lazy-init="false"> <property name="driverClass" value="com.mysql.jdbc.Driver" /> <property name="jdbcUrl" value="jdbc:mysql://localhost:3306/wms" /> <property name="user" value="root" /> <property name="password" value="123" /> <!--连接池中保留的最小连接数。 --> <property name="minPoolSize"> <value>5</value> </property> <!--连接池中保留的最大连接数。Default: 15 --> <property name="maxPoolSize"> <value>30</value> </property> <!--初始化时获取的连接数，取值应在minPoolSize与maxPoolSize之间。Default: 3 --> <property name="initialPoolSize"> <value>10</value> </property> <!--最大空闲时间,60秒内未使用则连接被丢弃。若为0则永不丢弃。Default: 0 --> <property name="maxIdleTime"> <value>60</value> </property> <!--当连接池中的连接耗尽的时候c3p0一次同时获取的连接数。Default: 3 --> <property name="acquireIncrement"> <value>5</value> </property> <!-- JDBC的标准参数，用以控制数据源内加载的PreparedStatements数量。但由于预缓存的statements 属于单个connection而不是整个连接池。所以设置这个参数需要考虑到多方面的因素。 如果maxStatements与maxStatementsPerConnection均为0，则缓存被关闭。Default: 0 --> <property name="maxStatements"> <value>0</value> </property> <!--每60秒检查所有连接池中的空闲连接。Default: 0 --> <property name="idleConnectionTestPeriod"> <value>60</value> </property> <!--定义在从数据库获取新连接失败后重复尝试的次数。Default: 30 --> <property name="acquireRetryAttempts"> <value>30</value> </property> <!-- 获取连接失败将会引起所有等待连接池来获取连接的线程抛出异常。但是数据源仍有效 保留，并在下次调用getConnection()的时候继续尝试获取连接。如果设为true，那么在尝试 获取连接失败后该数据源将申明已断开并永久关闭。Default: false --> <property name="breakAfterAcquireFailure"> <value>true</value> </property> <!-- 因性能消耗大请只在需要的时候使用它。如果设为true那么在每个connection提交的 时候都将校验其有效性。建议使用idleConnectionTestPeriod或automaticTestTable 等方法来提升连接测试的性能。Default: false --> <property name="testConnectionOnCheckout"> <value>false</value> </property> </bean> <!-- 配置Jdbc模板 --> <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate" lazy-init="false"> <property name="dataSource" ref="dataSource" /> </bean> <bean id="baseDAO" class="com.sani.dao.imp.BaseDao" lazy-init="false"> <property name="jdbcTemplate" ref="jdbcTemplate" /> </bean> </beans> ``` 现在只要调用action—test就会空指针 是什么原因？应该这么改？

java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]

idea中springboot内置tomcat起不起来 pom.xml： <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.2.1.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.aipuer</groupId> <artifactId>spring-boot</artifactId> <version>0.0.1-SNAPSHOT</version> <name>spring-boot</name> <description>Demo project for Spring Boot</description> <properties> <java.version>11</java.version> </properties> <dependencies> <!-- springBoot 的启动器 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <!-- springBoot 的启动器 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-thymeleaf</artifactId> </dependency> <!-- Mybatis 启动器 --> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.1.1</version> </dependency> <!-- mysql 数据库驱动 --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> </dependency> <!-- druid 数据库连接池 --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.0.9</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>1.5.9.RELEASE</version> </plugin> </plugins> </build> </project> 错误代码： 2019-12-03 10:08:21.181 INFO 7936 --- [ main] com.aipuer.springboot.Application : Starting Application on PC-20191121IKBV with PID 7936 (E:\java\develop\javacode\spring-boot\target\classes started by Administrator in E:\java\develop\javacode\spring-boot) 2019-12-03 10:08:21.183 INFO 7936 --- [ main] com.aipuer.springboot.Application : No active profile set, falling back to default profiles: default 2019-12-03 10:08:21.554 WARN 7936 --- [ main] o.m.s.mapper.ClassPathMapperScanner : No MyBatis mapper was found in '[com.aipuer.springboot]' package. Please check your configuration. 2019-12-03 10:08:21.839 INFO 7936 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http) 2019-12-03 10:08:21.844 INFO 7936 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat] 2019-12-03 10:08:21.844 INFO 7936 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.27] 2019-12-03 10:08:21.888 ERROR 7936 --- [ main] org.apache.catalina.core.ContainerBase : A child container failed during start java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at java.base/java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[na:na] at java.base/java.util.concurrent.FutureTask.get(FutureTask.java:191) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:916) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:841) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardService.startInternal(StandardService.java:421) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:930) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.startup.Tomcat.start(Tomcat.java:459) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:107) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:88) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:438) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:191) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:180) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:153) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:544) ~[spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at com.aipuer.springboot.Application.main(Application.java:10) ~[classes/:na] Caused by: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at org.apache.catalina.util.LifecycleBase.handleSubClassException(LifecycleBase.java:440) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:198) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardPipeline.startInternal(StandardPipeline.java:176) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5063) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 29 common frames omitted Caused by: java.lang.NoSuchMethodError: 'java.lang.String javax.servlet.ServletContext.getVirtualServerName()' at org.apache.catalina.authenticator.AuthenticatorBase.startInternal(AuthenticatorBase.java:1220) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 39 common frames omitted 2019-12-03 10:08:21.889 ERROR 7936 --- [ main] org.apache.catalina.core.ContainerBase : A child container failed during start java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: A child container failed during start at java.base/java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[na:na] at java.base/java.util.concurrent.FutureTask.get(FutureTask.java:191) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:916) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardService.startInternal(StandardService.java:421) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:930) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.startup.Tomcat.start(Tomcat.java:459) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:107) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:88) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:438) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:191) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:180) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:153) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:544) ~[spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE] at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE] at com.aipuer.springboot.Application.main(Application.java:10) ~[classes/:na] Caused by: org.apache.catalina.LifecycleException: A child container failed during start at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:928) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:841) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 21 common frames omitted Caused by: java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at java.base/java.util.concurrent.FutureTask.report(FutureTask.java:122) ~[na:na] at java.base/java.util.concurrent.FutureTask.get(FutureTask.java:191) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:916) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 29 common frames omitted Caused by: org.apache.catalina.LifecycleException: Failed to start component [NonLoginAuthenticator[StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[]]] at org.apache.catalina.util.LifecycleBase.handleSubClassException(LifecycleBase.java:440) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:198) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardPipeline.startInternal(StandardPipeline.java:176) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5063) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na] at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140) ~[na:na] at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 29 common frames omitted Caused by: java.lang.NoSuchMethodError: 'java.lang.String javax.servlet.ServletContext.getVirtualServerName()' at org.apache.catalina.authenticator.AuthenticatorBase.startInternal(AuthenticatorBase.java:1220) ~[tomcat-embed-core-9.0.27.jar:9.0.27] at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27] ... 39 common frames omitted 2019-12-03 10:08:21.889 INFO 7936 --- [ main] o.apache.catalina.core.StandardService : Stopping service [Tomcat] 2019-12-03 10:08:21.900 WARN 7936 --- [ main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat 2019-12-03 10:08:21.906 INFO 7936 --- [ main] ConditionEvaluationReportLoggingListener : Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled. 2019-12-03 10:08:21.909 ERROR 7936 --- [ main] o.s.b.d.LoggingFailureAnalysisReporter : *************************** APPLICATION FAILED TO START *************************** Description: An attempt was made to call a method that does not exist. The attempt was made from the following location: org.apache.catalina.authenticator.AuthenticatorBase.startInternal(AuthenticatorBase.java:1220) The following method did not exist: 'java.lang.String javax.servlet.ServletContext.getVirtualServerName()' The method's class, javax.servlet.ServletContext, is available from the following locations: jar:file:/E:/java/develop/javacode/spring-boot/lib/javaee.jar!/javax/servlet/ServletContext.class jar:file:/E:/maven/maven_repository/org/apache/tomcat/embed/tomcat-embed-core/9.0.27/tomcat-embed-core-9.0.27.jar!/javax/servlet/ServletContext.class It was loaded from the following location: file:/E:/java/develop/javacode/spring-boot/lib/javaee.jar Action: Correct the classpath of your application so that it contains a single, compatible version of javax.servlet.ServletContext Disconnected from the target VM, address: '127.0.0.1:52758', transport: 'socket' Process finished with exit code 1

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