mybatis sql中查询获取不到值


select brt.rtid,brtc.categoryname,brt.templatename,brt.templatesql,brt.templatetitle,brt.templatesumcolumns,brt.empcreatecode,brt.empcreatename,brt.createtime,brt.empmodifycode,brt.empmodifyname,brt.modifytime,brt.isenable,brt.counter
from bi_reports_template brt left join bi_reports_template_category brtc on brt.rtcid=brtc.rtcid where 1=1

and brt.templateName = #{templatename,jdbcType=VARCHAR}

order by brt.rtid

sql如上,
and brt.templateName = #{templatename,jdbcType=VARCHAR}

获取不到templatename值什么原因哦???

1个回答

楼主说的是#{templatename,jdbcType=VARCHAR} 里面的templatename没有值吧? 那你贴mybatis的xml 类似< select id="findList" resultType="TbJob " > 这样的东西是怎么写的? 方法参数是怎么写的? 有没有确认传了有效值等!!!!!!!!

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# UserMapper ``` public interface UserMapper { //根据id查询用户信息 public User findUserById(int id) throws Exception; //根据用户名列查询用户列表 public List<User> findUserByName(String name)throws Exception; //插入用户 public void insertUser(User user)throws Exception; } ``` # UserMapper.xml ``` <?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <!-- namespace命名空间,作用就是对sql进行分类化管理,理解sql隔离 注意:使用mapper代理方法开发,namespace有特殊重要的作用,namespace等于mapper接口地址 --> <mapper namespace="com.neuedu.mapper.UserMapper"> <!-- 在 映射文件中配置很多sql语句 --> <!-- 需求:通过id查询用户表的记录 --> <!-- 通过 select执行数据库查询 id:标识 映射文件中的 sql 将sql语句封装到mappedStatement对象中,所以将id称为statement的id parameterType:指定输入 参数的类型,这里指定int型 #{}表示一个占位符号 #{id}:其中的id表示接收输入 的参数,参数名称就是id,如果输入 参数是简单类型,#{}中的参数名可以任意,可以value或其它名称 resultType:指定sql输出结果 的所映射的java对象类型,select指定resultType表示将单条记录映射成的java对象。 --> <select id="findUserById" parameterType="int" resultType="user"> SELECT * FROM user WHERE id=#{value} </select> <!-- 根据用户名称模糊查询用户信息,可能返回多条 resultType:指定就是单条记录所映射的java对象 类型 ${}:表示拼接sql串,将接收到参数的内容不加任何修饰拼接在sql中。 使用${}拼接sql,引起 sql注入 ${value}:接收输入 参数的内容,如果传入类型是简单类型,${}中只能使用value --> <select id="findUserByName" parameterType="java.lang.String" resultType="com.neuedu.pojo.User"> SELECT * FROM user WHERE username LIKE '%${value}%' </select> <!-- 添加用户 parameterType:指定输入 参数类型是pojo(包括 用户信息) #{}中指定pojo的属性名,接收到pojo对象的属性值,mybatis通过OGNL获取对象的属性值 --> <insert id="insertUser" parameterType="com.neuedu.pojo.User"> <!-- 将插入数据的主键返回,返回到user对象中 SELECT LAST_INSERT_ID():得到刚insert进去记录的主键值,只适用与自增主键 keyProperty:将查询到主键值设置到parameterType指定的对象的哪个属性 order:SELECT LAST_INSERT_ID()执行顺序,相对于insert语句来说它的执行顺序 resultType:指定SELECT LAST_INSERT_ID()的结果类型 --> insert into user(id,username,birthday,sex,address) values (seq_user.nextval,#{username},#{birthday},#{sex},#{address}) <!-- 插入数据后,返回自动增长列的ID值,将sql语句的返回值赋给parameterType绑定对象的ID属性 MySQL中使用: select LAST_INSERT_ID() --> <selectKey keyProperty="id" order="AFTER" resultType="int"> SELECT LAST_INSERT_ID() <!--select seq_user.currval from dual--> </selectKey> <!-- 使用mysql的uuid()生成主键 执行过程: 首先通过uuid()得到主键,将主键设置到user对象的id属性中 其次在insert执行时,从user对象中取出id属性值 --> <!-- <selectKey keyProperty="id" order="BEFORE" resultType="java.lang.String"> SELECT uuid() </selectKey> insert into user(id,username,birthday,sex,address) value(#{id},#{username},#{birthday},#{sex},#{address}) --> </insert> <!-- 删除 用户 根据id删除用户,需要输入 id值 --> <delete id="deleteUser" parameterType="java.lang.Integer"> delete from user where id=#{id} </delete> <!-- 根据id更新用户 分析: 需要传入用户的id 需要传入用户的更新信息 parameterType指定user对象,包括 id和更新信息,注意:id必须存在 #{id}:从输入 user对象中获取id属性值 --> <update id="updateUser" parameterType="com.neuedu.pojo.User"> update user set username=#{username},birthday=#{birthday},sex=#{sex},address=#{address} where id=#{id} </update> </mapper> ``` # Tset ``` public class UserMapperTest { private SqlSessionFactory sqlSessionFactory; // 此方法是在执行testFindUserById之前执行 @Before public void setUp() throws Exception { // 创建sqlSessionFactory // mybatis配置文件 String resource = "config/SqlMapConfig.xml"; // 得到配置文件流 InputStream inputStream = Resources.getResourceAsStream(resource); // 创建会话工厂,传入mybatis的配置文件信息 sqlSessionFactory = new SqlSessionFactoryBuilder() .build(inputStream); } @Test public void testFindUserById() throws Exception { SqlSession sqlSession = sqlSessionFactory.openSession(); //创建UserMapper对象,mybatis自动生成mapper代理对象 UserMapper userMapper = sqlSession.getMapper(UserMapper.class); //调用userMapper的方法 User user = userMapper.findUserById(1); System.out.println(user); } @Test public void testFindUserByName() throws Exception { SqlSession sqlSession = sqlSessionFactory.openSession(); //创建UserMapper对象,mybatis自动生成mapper代理对象 UserMapper userMapper = sqlSession.getMapper(UserMapper.class); //调用userMapper的方法 List<User> list = userMapper.findUserByName("袁超"); sqlSession.close(); System.out.println(list); } } ``` # 报错信息 ``` DEBUG [main] - Logging initialized using 'class org.apache.ibatis.logging.slf4j.Slf4jImpl' adapter. DEBUG [main] - Class not found: org.jboss.vfs.VFS DEBUG [main] - JBoss 6 VFS API is not available in this environment. DEBUG [main] - Class not found: org.jboss.vfs.VirtualFile DEBUG [main] - VFS implementation org.apache.ibatis.io.JBoss6VFS is not valid in this environment. DEBUG [main] - Using VFS adapter org.apache.ibatis.io.DefaultVFS DEBUG [main] - Find JAR URL: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/pojo DEBUG [main] - Not a JAR: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/pojo DEBUG [main] - Reader entry: User.class DEBUG [main] - Listing file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/pojo DEBUG [main] - Find JAR URL: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/pojo/User.class DEBUG [main] - Not a JAR: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/pojo/User.class DEBUG [main] - Reader entry: ���� 1 N DEBUG [main] - Checking to see if class com.neuedu.pojo.User matches criteria [is assignable to Object] DEBUG [main] - PooledDataSource forcefully closed/removed all connections. DEBUG [main] - PooledDataSource forcefully closed/removed all connections. DEBUG [main] - PooledDataSource forcefully closed/removed all connections. DEBUG [main] - PooledDataSource forcefully closed/removed all connections. DEBUG [main] - Find JAR URL: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/test-classes/com/neuedu/mapper DEBUG [main] - Not a JAR: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/test-classes/com/neuedu/mapper DEBUG [main] - Reader entry: UserMapperTest.class DEBUG [main] - Listing file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/test-classes/com/neuedu/mapper DEBUG [main] - Find JAR URL: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/test-classes/com/neuedu/mapper/UserMapperTest.class DEBUG [main] - Not a JAR: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/test-classes/com/neuedu/mapper/UserMapperTest.class DEBUG [main] - Reader entry: ���� 1 a DEBUG [main] - Find JAR URL: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/mapper DEBUG [main] - Not a JAR: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/mapper DEBUG [main] - Reader entry: UserMapper.class DEBUG [main] - Reader entry: UserMapper.xml DEBUG [main] - Listing file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/mapper DEBUG [main] - Find JAR URL: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/mapper/UserMapper.class DEBUG [main] - Not a JAR: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/mapper/UserMapper.class DEBUG [main] - Reader entry: ���� 1    findUserById (I)Lcom/neuedu/pojo/User; DEBUG [main] - Find JAR URL: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/mapper/UserMapper.xml DEBUG [main] - Not a JAR: file:/C:/Users/95638/Desktop/mybatis/ch02-mybatis01/ch02-mybatis01/target/classes/com/neuedu/mapper/UserMapper.xml DEBUG [main] - Reader entry: <?xml version="1.0" encoding="UTF-8" ?> DEBUG [main] - Checking to see if class com.neuedu.mapper.UserMapperTest matches criteria [is assignable to Object] DEBUG [main] - Checking to see if class com.neuedu.mapper.UserMapper matches criteria [is assignable to Object] DEBUG [main] - Opening JDBC Connection DEBUG [main] - Created connection 209833425. DEBUG [main] - Setting autocommit to false on JDBC Connection [com.mysql.jdbc.JDBC4Connection@c81cdd1] DEBUG [main] - ==> Preparing: SELECT * FROM T_USER WHERE username LIKE '%袁超%' DEBUG [main] - ==> Parameters: org.apache.ibatis.exceptions.PersistenceException: ### Error querying database. Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'mybatis.t_user' doesn't exist ### The error may exist in com/neuedu/mapper/UserMapper.xml ### The error may involve com.neuedu.mapper.UserMapper.findUserByName-Inline ### The error occurred while setting parameters ### SQL: SELECT * FROM T_USER WHERE username LIKE '%袁超%' ### Cause: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'mybatis.t_user' doesn't exist at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:150) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) 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.$Proxy3.findUserByName(Unknown Source) at com.neuedu.mapper.UserMapperTest.testFindUserByName(UserMapperTest.java:68) 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.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44) at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17) at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26) at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70) at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229) at org.junit.runners.ParentRunner.run(ParentRunner.java:309) at org.junit.runner.JUnitCore.run(JUnitCore.java:160) at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68) at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47) at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242) at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70) Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'mybatis.t_user' doesn't exist at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45) at java.lang.reflect.Constructor.newInstance(Constructor.java:423) at com.mysql.jdbc.Util.handleNewInstance(Util.java:400) at com.mysql.jdbc.Util.getInstance(Util.java:383) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:980) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3847) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3783) at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2447) at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2594) at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2545) at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1901) at com.mysql.jdbc.PreparedStatement.execute(PreparedStatement.java:1193) 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.apache.ibatis.logging.jdbc.PreparedStatementLogger.invoke(PreparedStatementLogger.java:59) at com.sun.proxy.$Proxy5.execute(Unknown Source) at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:63) at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:79) at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:63) at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:324) at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109) at org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:83) at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) ... 29 more ``` # SqlMapConfig.xml ``` <?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <!-- 加载属性文件 --> <properties resource="db.properties"> <!--properties中还可以配置一些属性名和属性值 --> <!-- <property name="jdbc.driver" value=""/> --> </properties> <!-- 全局配置参数,需要时再设置 --> <!-- <settings> </settings> --> <!-- 别名定义 --> <typeAliases> <!-- 针对单个别名定义 type:类型的路径 alias:别名 --> <!-- <typeAlias type="com.neuedu.mybatis.po.User" alias="user"/> --> <!-- 批量别名定义 指定包名,mybatis自动扫描包中的po类,自动定义别名,别名就是类名(首字母大写或小写都可以) --> <package name="com.neuedu.pojo"/> </typeAliases> <!-- 和spring整合后 environments配置将废除--> <environments default="development"> <environment id="development"> <!-- 使用jdbc事务管理,事务控制由mybatis--> <transactionManager type="JDBC" /> <!-- 数据库连接池,由mybatis管理--> <dataSource type="POOLED"> <property name="driver" value="${jdbc.driver}" /> <property name="url" value="${jdbc.url}" /> <property name="username" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> </dataSource> </environment> </environments> <!-- 加载 映射文件 --> <mappers> <mapper resource="sqlmap/User.xml"/> <!--通过resource方法一次加载一个映射文件 --> <!-- <mapper resource="sqlmap/User.xml"/> --> <!-- 通过mapper接口加载单个 映射文件 遵循一些规范:需要将mapper接口类名和mapper.xml映射文件名称保持一致,且在一个目录 中 上边规范的前提是:使用的是mapper代理方法 --> <!-- <mapper class="com.neuedu.mapper.UserMapper"/> --> <!-- 批量加载mapper 指定mapper接口的包名,mybatis自动扫描包下边所有mapper接口进行加载 遵循一些规范:需要将mapper接口类名和mapper.xml映射文件名称保持一致,且在一个目录 中 上边规范的前提是:使用的是mapper代理方法 --> <package name="com.neuedu.mapper"/> </mappers> </configuration> ``` # User ``` public class User { //属性名和数据库表的字段对应 private int id; private String username;// 用户姓名 private String sex;// 性别 private Date birthday;// 生日 private String address;// 地址 public int getId() { return id; } public void setId(int id) { this.id = id; } public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getSex() { return sex; } public void setSex(String sex) { this.sex = sex; } public Date getBirthday() { return birthday; } public void setBirthday(Date birthday) { this.birthday = birthday; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } @Override public String toString() { return "User [id=" + id + ", username=" + username + ", sex=" + sex + ", birthday=" + birthday + ", address=" + address + "]"; } } ``` 也不知道为什么,明明已经在UserMapper.xml里面把表名改了,但是报错信息里查找的还是T-user表 求大神指导!感恩! # 问题已解决 在maven文件里加上下面的代码 ``` <resources> <resource> <directory>src/main/java</directory> <includes> <include>**/*Mapper.xml</include> </includes> </resource> </resources> ```
xmemcached和整合SSM框架 单元测试没问提 项目启动后造成mybatis连接不到数据库?
路径是没问提的 本来一切正常 我在原来的基础上整合了memcached。 memcached测试链接对数据进行操作没问题 但是项目运行起来以后 mybatis无法链接数据库; 注释掉memcached配置 就会回复正常 ## memcached.xml <!-- properties config --> <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="order" value="1" /> <property name="ignoreUnresolvablePlaceholders" value="true" /> <property name="locations"> <list> <value>classpath:config/memcached.properties</value> </list> </property> </bean> <!-- Memcached配置 --> <!-- p:connectionPoolSize="${memcached.connectionPoolSize}" p:failureMode="${memcached.failureMode}" --> <bean id="memcachedClientBuilder" class="net.rubyeye.xmemcached.XMemcachedClientBuilder"> <constructor-arg> <list> <bean class="java.net.InetSocketAddress"> <constructor-arg> <value>${memcached.server1.host}</value> </constructor-arg> <constructor-arg> <value>${memcached.server1.port}</value> </constructor-arg> </bean> </list> </constructor-arg> <constructor-arg> <list> <value>${memcached.server1.weight}</value> </list> </constructor-arg> <property name="commandFactory"> <bean class="net.rubyeye.xmemcached.command.TextCommandFactory" /> </property> <property name="sessionLocator"> <bean class="net.rubyeye.xmemcached.impl.KetamaMemcachedSessionLocator" /> </property> <property name="transcoder"> <bean class="net.rubyeye.xmemcached.transcoders.SerializingTranscoder" /> </property> <property name="connectionPoolSize" value="${memcached.connectionPoolSize}" /> <property name="failureMode" value="${memcached.failureMode}" /> </bean> <!-- Use factory bean to build memcached client --> <bean id="memcachedClient" factory-bean="memcachedClientBuilder" factory-method="build" destroy-method="shutdown" /> ## mybatis <!-- 引入配置文件 --> <bean id="propertyConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> <property name="location" value="classpath:config/jdbc.properties" /> </bean> <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"> <property name="driverClassName" value="${driver}" /> <property name="url" value="${url}" /> <property name="username" value="${username}" /> <property name="password" value="${password}" /> <!-- 初始化连接大小 --> <property name="initialSize" value="${initialSize}"></property> <!-- 连接池最大数量 --> <property name="maxActive" value="${maxActive}"></property> <!-- 连接池最大空闲 --> <property name="maxIdle" value="${maxIdle}"></property> <!-- 连接池最小空闲 --> <property name="minIdle" value="${minIdle}"></property> <!-- 获取连接最大等待时间 --> <property name="maxWait" value="${maxWait}"></property> </bean> <!--spring与mybatis整合 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <property name="dataSource" ref="dataSource" /> <!-- 自动扫描mapping.xml文件 --> <property name="mapperLocations" value="classpath:mapping/**/*.xml"> </property> <!-- 全局配置 --> <!-- 若不保留mybatis配置文件用上面那条替换这一条 --> <!-- <property name="configLocation" value="classpath:mybatis/sqlMapConfig.xml"/> --> <!-- mybatis配置文件路径 --> <property name="configLocation" value="classpath:/config/spring/mybatis.xml" /> </bean> <!-- DAO接口所在包名,Spring会自动查找其下的类 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <!-- 扫描包路径,需要扫描多个包中间用逗号隔开 --> <property name="basePackage" value="com.ysjian.bud.app.dao,com.ysjian.bud.backstage.dao" /> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property> </bean> ## 运行错误信息 org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.exceptions.PersistenceException: Error updating database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:75) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:371) at com.sun.proxy.$Proxy16.delete(Unknown Source) at org.mybatis.spring.SqlSessionTemplate.delete(SqlSessionTemplate.java:268) at org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:57) at org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:52) at com.sun.proxy.$Proxy34.deleteSayHi(Unknown Source) at appLoginTest.BUDTest.Test1(BUDTest.java:46) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44) at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17) at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:74) at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:83) at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:72) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:232) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:89) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229) at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:71) at org.junit.runners.ParentRunner.run(ParentRunner.java:309) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:175) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:539) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:761) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:461) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:207) Caused by: org.apache.ibatis.exceptions.PersistenceException: ### Error updating database. Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:26) at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:154) at org.apache.ibatis.session.defaults.DefaultSqlSession.delete(DefaultSqlSession.java:165) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:358) ... 34 more Caused by: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:80) at org.mybatis.spring.transaction.SpringManagedTransaction.openConnection(SpringManagedTransaction.java:81) at org.mybatis.spring.transaction.SpringManagedTransaction.getConnection(SpringManagedTransaction.java:67) at org.apache.ibatis.executor.BaseExecutor.getConnection(BaseExecutor.java:279) at org.apache.ibatis.executor.SimpleExecutor.prepareStatement(SimpleExecutor.java:72) at org.apache.ibatis.executor.SimpleExecutor.doUpdate(SimpleExecutor.java:47) at org.apache.ibatis.executor.BaseExecutor.update(BaseExecutor.java:105) at org.apache.ibatis.executor.CachingExecutor.update(CachingExecutor.java:71) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:62) at com.sun.proxy.$Proxy54.update(Unknown Source) at org.apache.ibatis.session.defaults.DefaultSqlSession.update(DefaultSqlSession.java:152) ... 40 more Caused by: org.apache.commons.dbcp.SQLNestedException: Cannot create PoolableConnectionFactory (Could not create connection to database server. Attempted reconnect 3 times. Giving up.) at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1225) at org.apache.commons.dbcp.BasicDataSource.getConnection(BasicDataSource.java:880) at org.springframework.jdbc.datasource.DataSourceUtils.doGetConnection(DataSourceUtils.java:111) at org.springframework.jdbc.datasource.DataSourceUtils.getConnection(DataSourceUtils.java:77) ... 54 more Caused by: com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: Could not create connection to database server. Attempted reconnect 3 times. Giving up. at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at com.mysql.jdbc.Util.handleNewInstance(Util.java:409) at com.mysql.jdbc.Util.getInstance(Util.java:384) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1013) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:987) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:973) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:918) at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2405) at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2326) at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:832) at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:46) at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) at java.lang.reflect.Constructor.newInstance(Unknown Source) at com.mysql.jdbc.Util.handleNewInstance(Util.java:409) at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:417) at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:344) at org.apache.commons.dbcp.DriverConnectionFactory.createConnection(DriverConnectionFactory.java:38) at org.apache.commons.dbcp.PoolableConnectionFactory.makeObject(PoolableConnectionFactory.java:294) at org.apache.commons.dbcp.BasicDataSource.validateConnectionFactory(BasicDataSource.java:1247) at org.apache.commons.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1221) ... 57 more Caused by: java.sql.SQLException: Access denied for user 'DELL'@'localhost' (using password: YES) at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1084) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4232) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4164) at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:926) at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1748) at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1288) at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2506) at com.mysql.jdbc.ConnectionImpl.connectWithRetries(ConnectionImpl.java:2344) ... 71 more
mybatis拦截器分页问题。intercept有时候不执行
我在SSM工程中使用mybatis拦截器做分页,但是拦截器的intercept有时候执行有时候不执行,不知道为什么,程序员没有没有经验呢?谢谢赐教 代码: @Intercepts({@Signature(type = StatementHandler.class, method = "prepare", args = { Connection.class })}) public class PageInterceptor implements Interceptor { private static String sqlId = ""; private static String dialect = ""; public Object intercept(Invocation inv) throws Throwable { System.out.println("到了"); RoutingStatementHandler handler = (RoutingStatementHandler) inv.getTarget(); StatementHandler delegate = (StatementHandler)ReflectionUtils.getFieldValue(handler, "delegate"); MappedStatement mappedStatement = (MappedStatement) ReflectionUtils.getFieldValue(delegate, "mappedStatement"); if(mappedStatement.getId().matches(sqlId)) { //只拦截id包含pages的SQL BoundSql bound = delegate.getBoundSql(); //获得当前绑定Sql的参数对象 Object object = bound.getParameterObject(); if(object == null) { return inv.proceed(); } if(object instanceof PageEntity<?>) { PageEntity<?> page = (PageEntity<?>)object; String sql = bound.getSql(); String pageSql = getPageSql(sql, page); ReflectionUtils.setFieldValue(bound, "sql", pageSql); } } return inv.proceed(); } public String getPageSql(String sql, PageEntity<?> page) { //此处省略SQL拼接代码 return pageSql.toString(); } public Object plugin(Object arg0) { return Plugin.wrap(arg0, this); } public void setProperties(Properties property) { sqlId = property.getProperty("sqlId"); //".*Pages*.*" dialect = property.getProperty("dialect"); //"oracle" } } 配置: <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE configuration PUBLIC "-//ibatis.apache.org//DTD Config 3.0//EN" "http://ibatis.apache.org/dtd/ibatis-3-config.dtd"> <configuration> <settings> <setting name="cacheEnabled" value="true" /> <setting name="lazyLoadingEnabled" value="true" /> <setting name="multipleResultSetsEnabled" value="true" /> <setting name="useColumnLabel" value="true" /> <setting name="useGeneratedKeys" value="false" /> <setting name="defaultExecutorType" value="SIMPLE" /> </settings> <typeAliases> <typeAlias type="com.cifpay.user.entity.UserEntity" alias="user" /> <typeAlias type="com.cifpay.role.entity.RoleEntity" alias="role" /> <typeAlias type="com.cifpay.menu.entity.MenuEntity" alias="menu" /> <typeAlias type="com.cifpay.role.entity.RoleMenuMapEntity" alias="roleMenuMap" /> <typeAlias type="com.cifpay.role.entity.UserRoleMapEntity" alias="userRoleMap" /> </typeAliases> <plugins> <plugin interceptor="com.cifpay.base.interceptor.PageInterceptor"> <property name="sqlId" value=".*Pages*.*"/> <property name="dialect" value="oracle"/> </plugin> </plugins> <mappers> <mapper resource="com/cifpay/user/entity/User.sqlMap.xml" /> <mapper resource="com/cifpay/role/entity/Role.sqlMap.xml" /> <mapper resource="com/cifpay/menu/entity/Menu.sqlMap.xml"/> <mapper resource="com/cifpay/role/entity/RoleMenuMap.sqlMap.xml"/> <mapper resource="com/cifpay/role/entity/UserRoleMap.sqlMap.xml"/> </mappers> </configuration>
基于springmvc+mybatis的登录表单提交后404
前端填写正确的用户名和密码后,提交登录,浏览器显示404,前端提交的地址是/userlogin,后端对接的/user/userlogin也是对的,浏览器f12里显示请求的确成功传给了后端,但是不知道为什么404。用的是tomcat8.5,java版本1.8,phpstudy最新版,mysql5.7.26。 ## 这是所用到的包: ![图片说明](https://img-ask.csdn.net/upload/202002/01/1580567617_880785.jpg) ## 这是目录结构: ![图片说明](https://img-ask.csdn.net/upload/202002/01/1580567511_223692.jpg) ## 这是web.xml: ```xml <?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5"> <display-name>springmvc_test</display-name> <welcome-file-list> <welcome-file>index.html</welcome-file> <welcome-file>index.jsp</welcome-file> </welcome-file-list> <!-- 配置spring监听器 --> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <!-- 加载spring配置文件 --> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath*:config/context-config.xml</param-value> </context-param> <!-- 配置前端控制器 --> <servlet> <servlet-name>springmvc</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <!-- DispatcherServlet在初始化方法里面会读取该初始化参数的值来获得 spring配置文件的位置 ,然后启动spring容器。 --> <param-name>contextConfigLocation</param-name> <param-value>classpath*:config/springmvc-config.xml</param-value> </init-param> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>springmvc</servlet-name> <url-pattern>/</url-pattern> </servlet-mapping> <!-- 配置字符编码 --> <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> </filter> <filter-mapping> <filter-name>encodingFilter</filter-name> <url-pattern>/*</url-pattern> </filter-mapping> </web-app> ``` ## 这是context-config.xml: ```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:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <!-- 扫描service包下的注解 --> <context:component-scan base-package="com.test.service"></context:component-scan> <!-- 配置数据库 --> <!-- 加载配置文件 --> <!-- <context:property-placeholder location="classpath:jdbc.properties"/> --> <bean id="dateSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <property name="driver" value="com.mysql.jdbc.Driver"></property> <property name="url" value="jdbc:mysql://localhost:3306/Eday_Test"></property> <property name="username" value="root"></property> <property name="password" value="123456"></property> </bean> <!-- 配置Sqlsessionfactory并将数据源注入 --> <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean"> <!-- 引入数据源 --> <property name="dateSource" ref="dateSource"></property> <!-- 载入mybatis配置文件 --> <property name="configLocation" value="classpath:mybatis-config.xml"></property> <!-- 载入配置mapper映射的xml --> <property name="mapperLocations" value="classpath:com/test/mapper/*.xml"></property> </bean> <!-- 配置扫描mapper接口 --> <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer"> <property name="basePackge" value="com.test.mapper"></property> <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"></property> </bean> <!-- 配置事务管理器 --> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dateSource" ref="dateSource"></property> </bean> <tx:annotation-driven transaction-manager="transactionManager"/> </beans> ``` ## 这是mybatis-config.xml: ```xml <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <typeAliases> <!-- 配置别名 --> <typeAlias alias="User" type="com.test.pojo.User"/> </typeAliases> </configuration> ``` ## 这是springmvc-config.xml: ```xml <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context" 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/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd"> <!-- 扫描controller包下的注解 --> <context:component-scan base-package="com.test.controller"></context:component-scan> <!-- 开启注解 --> <mvc:annotation-driven></mvc:annotation-driven> <!-- 静态资源访问 --> <mvc:default-servlet-handler/> <!-- 视图解析器 --> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <!-- 配置试图解析的默认路径,即配置页面的根路径 --> <property name="prefix" value="/"></property> <property name="suffix" value=".jsp"></property> </bean> </beans> ``` ## 这是UserController.java: ```java package com.test.controller; import javax.servlet.http.HttpSession; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.context.annotation.Scope; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.servlet.ModelAndView; import com.test.pojo.User; import com.test.service.UserService; //声明控制器 @Controller //设置bean的scope属性为多例(prototype) @Scope("prototype") //设置请求映射,当客户端请求/user时,转到该控制器处理 @RequestMapping("/user") public class UserController { @Autowired private UserService userService; @RequestMapping(value="/userlogin") public ModelAndView login(String user_Name,String user_pwd,ModelAndView mv,HttpSession session){ //调用userService中的login方法处理user实体类对象 User user = userService.login(user_Name,user_pwd); //登录的逻辑判断,判断条件是返回结果不为空 if(user!=null){ //登陆成功,将user对象设置到HttpSession作用范围域中,相当于服务端的cookie,有效时间默认30分钟 //在程序运行期间,在任意页面都可以提取它的值。 session.setAttribute("user",user); //转发到main请求 //登录成功,跳转页面 mv.setViewName("login/login-success"); }else{ //登录失败,向前端传递失败信息 mv.addObject("message","用户名或密码错误,请重新输入!"); //登录失败,跳转到登录页面 mv.setViewName("login"); } return mv; } //跳转到用户注册界面 @RequestMapping(value="/userregister"/*,method=RequestMethod.POST*/) public String register(User user){ String user_Name = user.getUser_Name(); //如果数据库中没有该用户,可以注册,否则跳转页面 if(userService.findByUserName(user_Name)==null){ //添加用户 userService.register(user); //注册成功,跳转到主页面 return "index"; }else{ //注册失败,跳转到错误页面 return "error"; } } } ``` ## 这是UserMapper.java: ```java package com.test.mapper; import org.apache.ibatis.annotations.Param; import com.test.pojo.User; public interface UserMapper { //根据用户名和密码查找,mybatis中有多个参数时,需要使用@Param注解 User findByUserNameAndPassword(@Param("user_Name")String user_Name,@Param("user_Pwd")String user_Pwd); //增加用户 void addUser(User user); //根据用户名查询 User findByUserName(String user_Name); } ``` ## 这是UserMapper.xml: ```xml <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace="com.tes.mapper.UserMapper"> <!-- 根据用户名和密码查询 --> <select id="findByUserNameAndPasssword" resultType="User"> select * from user where user_Name=#{user_Name} and user_Pwd=#{user_Pwd} </select> <!-- 增加用户 --> <insert id="addUser" parameterType="User"> insert into user (user_Name,user_Pwd,user_Email,user_NickName,user_Birth,user_Phone,user_InvitationCode) values(#{user_Name},#{user_Pwd},#{user_Email},#{user_NickName},#{user_Birth},#{user_Phone},#{user_InvitationCode}) </insert> <!-- 根据用户名查询 --> <select id="findByUserName" resultType="User"> select * from user where user_Name=#{user_Name} </select> </mapper> ``` ## 这是User.java: ```java package com.test.pojo; import java.sql.Timestamp; public class User { private int user_Id; private String user_Name; private int user_Pwd; private String user_Email; private String user_NickName; private Timestamp user_Time; private String user_Birth; private int user_Fans; private int user_Follow; private int user_Score; private String user_HeadImgAddr; private int user_Phone; private String user_InvitationCode; public int getUser_Id() { return user_Id; } public void setUser_Id(int user_Id) { this.user_Id = user_Id; } public String getUser_Name() { return user_Name; } public void setUser_Name(String user_Name) { this.user_Name = user_Name; } public int getUser_Pwd() { return user_Pwd; } public void setUser_Pwd(int user_Pwd) { this.user_Pwd = user_Pwd; } public String getUser_Email() { return user_Email; } public void setUser_Email(String user_Email) { this.user_Email = user_Email; } public String getUser_NickName() { return user_NickName; } public void setUser_NickName(String user_NickName) { this.user_NickName = user_NickName; } public Timestamp getUser_Time() { return user_Time; } public void setUser_Time(Timestamp user_Time) { this.user_Time = user_Time; } public String getUser_Birth() { return user_Birth; } public void setUser_Birth(String user_Birth) { this.user_Birth = user_Birth; } public int getUser_Fans() { return user_Fans; } public void setUser_Fans(int user_Fans) { this.user_Fans = user_Fans; } public int getUser_Follow() { return user_Follow; } public void setUser_Follow(int user_Follow) { this.user_Follow = user_Follow; } public int getUser_Score() { return user_Score; } public void setUser_Score(int user_Score) { this.user_Score = user_Score; } public String getUser_HeadImgAddr() { return user_HeadImgAddr; } public void setUser_HeadImgAddr(String user_HeadImgAddr) { this.user_HeadImgAddr = user_HeadImgAddr; } public int getUser_Phone() { return user_Phone; } public void setUser_Phone(int user_Phone) { this.user_Phone = user_Phone; } public String getUser_InvitationCode() { return user_InvitationCode; } public void setUser_InvitationCode(String user_InvitationCode) { this.user_InvitationCode = user_InvitationCode; } @Override public String toString() { return "User [user_Id=" + user_Id + ", user_Name=" + user_Name + ", user_Pwd=" + user_Pwd + ", user_Email=" + user_Email + ", user_NickName=" + user_NickName + ", user_Time=" + user_Time + ", user_Birth=" + user_Birth + ", user_Fans=" + user_Fans + ", user_Follow=" + user_Follow + ", user_Score=" + user_Score + ", user_HeadImgAddr=" + user_HeadImgAddr + ", user_Phone=" + user_Phone + ", user_InvitationCode=" + user_InvitationCode + "]"; } } ``` ## 这是UserService.java: ```java package com.test.service; import com.test.pojo.User; public interface UserService { //通过用户名及密码核查用户登录 User login(String user_Name,String user_Pwd); //增加用户 void register(User user); //根据用户名查询 User findByUserName(String user); } ``` ## 这是UserServiceImpl.java: ```java package com.test.service.impl; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; import org.springframework.transaction.annotation.Transactional; import com.test.mapper.UserMapper; import com.test.pojo.User; import com.test.service.UserService; @Service @Transactional public class UserServiceImpl implements UserService { //注入UserMapper接口 @Autowired private UserMapper userMapper; //登录,根据用户名和密码进行查询 @Override public User login(String user_Name,String user_Pwd){ return userMapper.findByUserNameAndPassword(user_Name,user_Pwd); } //注册,增加用户 @Override public void register(User user){ userMapper.addUser(user); } //根据用户名查询 @Override public User findByUserName(String user_Name){ return userMapper.findByUserName(user_Name); } } ``` ##这是login.jsp ```jsp <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <link rel="stylesheet" type="text/css" href="../css/login.css" /> <title>登录</title> </head> <body> <!--导航栏--> <nav class="nav"> <ul> <li class="logo"><a href="#">Eday</a></li> <li class="shouye"><a href="../index.jsp" class="neirong">首页</a></li> <li class="fgx">|</li> <li><a href="#" class="neirong">文章列表</a></li> <li class="fgx">|</li> <li><a href="#" class="neirong">留言板</a></li> <li class="fgx">|</li> <li><a href="#" class="neirong">更新日志</a></li> </ul> </nav> <!--登录板块--> <header class="header"> <p class="logintitle"> <b>登录</b> </p> <form action="${pageContext.request.contextPath }/user/userlogin" method="post" class=login-form> <p class= login-username-p> <label for="username" class="login-username-text">用户名:</label> <input type=text name="user_Name" class="login-username-input"> <br><a href="register.jsp" class=login-register>注册</a> </p> <p class="login-psw-p"> <label for="psw" class="login-psw-text">密码:</label> <input type=password name="user_Pwd" class="login-psw-input"> <br><a href="#" class=login-forget>忘记密码</a> </p> <div class=login-button-div> <label for=button></label> <button type=sublim class=login-button>登录</button> </div> </form> </header> </body> </html> ``` ## 这是login-success.jsp: ```jsp <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>登录成功,请等待跳转...</title> <script type="text/javascript"> onload=function(){ setInterval(go, 1000); }; var x=3; //利用了全局变量来执行 function go(){ x--; if(x>0){ document.getElementById("sp").innerHTML=x; //每次设置的x的值都不一样了。 }else{ location.href='../index.jsp'; } } </script> </head> <body> <!--导航栏--> <nav class="nav"> <ul> <li class="logo"><a href="#">Eday</a></li> <li class="shouye"><a href="../index.jsp" class="neirong">首页</a></li> <li class="fgx">|</li> <li><a href="#" class="neirong">文章列表</a></li> <li class="fgx">|</li> <li><a href="#" class="neirong">留言板</a></li> <li class="fgx">|</li> <li><a href="#" class="neirong">更新日志</a></li> </ul> </nav> <header> <div> <p>登录成功!页面将在3秒后自动跳转,请稍等...</p> </div> </header> </body> </html> ``` ## 这是数据库: ![图片说明](https://img-ask.csdn.net/upload/202002/01/1580568589_694404.jpg)
spring boot mybatis 枚举错误,无法映射
spring boot mybatis 枚举错误 * 今天遇到一个问题,解决了好几个小时,没有搞定,搞到现在,有大佬可以帮我看下吗?万分感谢,没有分了,枚举映射,在idea中可以使用, 部署使用java -jar 方式就报错 * jdk1.8 * mybatis3.0.7.1 * application.yml环境为prod * ``` mybatis-plus: #枚举 typeHandlersPackage: com.xxx.common.module.handler ``` * 查询代码,不能转换 * ``` public LsAppEntity queryByAppKey(String appKey) { return this.getOne(new QueryWrapper<LsAppEntity>() .eq("app_key", appKey) .ne("status", StatusEnum.删除)); } ``` 1. Enum代码 ``` /** * Enum - 状态 * * @author xxx * @version 1.0.0 */ @JSONType(serializeEnumAsJavaBean = true) @JsonFormat(shape = JsonFormat.Shape.OBJECT) public enum StatusEnum implements BaseEnum<StatusEnum, Integer> { /** 删除 */ 删除(-1, "删除"), /** 无效 */ 无效(0, "无效"), /** 有效 */ 有效(1, "有效"); /** * 值. */ private Integer value; /** * 名称. */ private String name ; static { subClass.add(StatusEnum.class); } StatusEnum(Integer value, String name) { this.value = value; this.name = name; } @Override public Integer getValue() { return value; } public void setValue(Integer value) { this.value = value; } @Override public String getName() { return name; } public void setName(String name) { this.name = name; } //根据key获取枚举 public static StatusEnum getEnumByValue(Integer value){ if (null == value){ return null; } for(StatusEnum e: StatusEnum.values()){ if(e.getValue().equals(value)){ return e; } } return null; } } ``` 2. 枚举转换处理器 ``` package com.xxx.common.module.handler; import com.xxx.common.module.enums.*; import lombok.extern.slf4j.Slf4j; import org.apache.ibatis.type.BaseTypeHandler; import org.apache.ibatis.type.JdbcType; import org.apache.ibatis.type.MappedTypes; import java.sql.CallableStatement; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; /** * 枚举转换处理器 * * @author xxx * @version 1.0.0 */ @Slf4j @MappedTypes(value = {StatusEnum.class}) public final class BaseEnumTypeHandler<E extends BaseEnum> extends BaseTypeHandler<E> { private Class<E> type; private E[] enums; public BaseEnumTypeHandler() { } public BaseEnumTypeHandler(Class<E> type) { if (type == null) { throw new IllegalArgumentException("Type argument cannot be null"); } this.type = type; this.enums = this.type.getEnumConstants(); if (this.enums == null) { throw new IllegalArgumentException(type.getSimpleName() + " does not represent an enum type."); } } @Override public void setNonNullParameter(PreparedStatement ps, int i, E parameter, JdbcType jdbcType) throws SQLException { //BaseTypeHandler 进行非空校验 log.debug("index : {}, parameter : {},jdbcType : {} ", i, parameter.getValue(), jdbcType); if (jdbcType == null) { ps.setObject(i, parameter.getValue()); } else { ps.setObject(i, parameter.getValue(), jdbcType.TYPE_CODE); } } @Override public E getNullableResult(ResultSet rs, String columnName) throws SQLException { Object code = rs.getObject(columnName); if (rs.wasNull()) { return null; } return getEnmByCode(code); } @Override public E getNullableResult(ResultSet rs, int columnIndex) throws SQLException { Object code = rs.getObject(columnIndex); if (rs.wasNull()) { return null; } return getEnmByCode(code); } @Override public E getNullableResult(CallableStatement cs, int columnIndex) throws SQLException { Object code = cs.getObject(columnIndex); if (cs.wasNull()) { return null; } return getEnmByCode(code); } private E getEnmByCode(Object code) { if (code == null) { throw new NullPointerException("the result code is null " + code); } if (code instanceof Integer) { for (E e : enums) { if (e.getValue() == code) { return e; } } throw new IllegalArgumentException("Unknown enumeration type , please check the enumeration code : " + code); } if (code instanceof String) { for (E e : enums) { if (code.equals(e.getValue())) { return e; } } throw new IllegalArgumentException("Unknown enumeration type , please check the enumeration code : " + code); } throw new IllegalArgumentException("Unknown enumeration type , please check the enumeration code : " + code); } } ``` 3. 报错信息 2020-01-20 02:45:35.879 ERROR 2472 --- [nio-8081-exec-1] c.l.exception.RRExceptionHandler : nested exception is org.apache.ibatis.executor.result.ResultMapException: Error attempting to get column 'status' from result set. Cause: java.lang.IllegalArgumentException: No enum constant com.xxx.common.module.enums.StatusEnum.1 * org.mybatis.spring.MyBatisSystemException: nested exception is org.apache.ibatis.executor.result.ResultMapException: Error attempting to get column 'status' from result set. Cause: java.lang.IllegalArgumentException: No enum constant com.xxx.common.module.enums.StatusEnum.1 * at org.mybatis.spring.MyBatisExceptionTranslator.translateExceptionIfPossible(MyBatisExceptionTranslator.java:77) * at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:446) * at com.sun.proxy.$Proxy132.selectList(Unknown Source) * at org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:230) * at com.baomidou.mybatisplus.core.override.PageMapperMethod.executeForMany(PageMapperMethod.java:173) * at com.baomidou.mybatisplus.core.override.PageMapperMethod.execute(PageMapperMethod.java:86) * at com.baomidou.mybatisplus.core.override.PageMapperProxy.invoke(PageMapperProxy.java:64) * at com.sun.proxy.$Proxy137.selectList(Unknown Source) * at com.baomidou.mybatisplus.extension.service.impl.ServiceImpl.getOne(ServiceImpl.java:259) * at com.baomidou.mybatisplus.extension.service.IService.getOne(IService.java:230) * at com.xxx.common.module.service.impl.AppServiceImpl.queryByAppKey(AppServiceImpl.java:100) * at com.xxx.common.module.service.impl.AppServiceImpl$$FastClassBySpringCGLIB$$9380a940.invoke(<generated>) * at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) * at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:684) * at com.xxx.common.module.service.impl.AppServiceImpl$$EnhancerBySpringCGLIB$$307b01.queryByAppKey(<generated>) * at com.xxx.common.module.service.impl.AppInfoServiceImpl.validateBaseApi(AppInfoServiceImpl.java:141) * at com.xxx.common.module.service.impl.AppInfoServiceImpl.appInfo(AppInfoServiceImpl.java:157) * at com.xxx.common.module.service.impl.AppInfoServiceImpl$$FastClassBySpringCGLIB$$2bb67632.invoke(<generated>) * at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) * at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:684) * at com.xxx.common.module.service.impl.AppInfoServiceImpl$$EnhancerBySpringCGLIB$$8bd88917.appInfo(<generated>) * at com.xxx.controller.ApiAppProductController.list(ApiAppProductController.java:79) * 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:483) * at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:189) * at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138) * at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) * at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) * at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:800) * at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) * at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1038) * at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:942) * at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1005) * at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:908) * at javax.servlet.http.HttpServlet.service(HttpServlet.java:660) * at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:882) * at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) * at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) * at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) * at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) * at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) * at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) * at com.xxx.common.xss.XssFilter.doFilter(XssFilter.java:24) * at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) * at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) * at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) * at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) * at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) * at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) * at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:92) * at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) * at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) * at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) * at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:93) * at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) * at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) * at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) * at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:200) * at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) * at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) * at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) * at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) * at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) * at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:490) * at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) * at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) * at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) * at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) * at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:408) * at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) * at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:834) * at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1417) * 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) * Caused by: org.apache.ibatis.executor.result.ResultMapException: Error attempting to get column 'status' from result set. Cause: java.lang.IllegalArgumentException: No enum constant com.xxx.common.module.enums.StatusEnum.1 * at org.apache.ibatis.type.BaseTypeHandler.getResult(BaseTypeHandler.java:68) * at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.applyAutomaticMappings(DefaultResultSetHandler.java:520) * at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.getRowValue(DefaultResultSetHandler.java:401) * at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleRowValuesForSimpleResultMap(DefaultResultSetHandler.java:355) * at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleRowValues(DefaultResultSetHandler.java:330) * at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleResultSet(DefaultResultSetHandler.java:303) * at org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleResultSets(DefaultResultSetHandler.java:196) * at org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:64) * at org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:79) * 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:483) * at org.apache.ibatis.plugin.Plugin.invoke(Plugin.java:63) * at com.sun.proxy.$Proxy200.query(Unknown Source) * at org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:63) * at org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:326) * at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156) * at org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:136) * at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:148) * at org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:141) * at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) * at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) * at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) * at java.lang.reflect.Method.invoke(Method.java:483) * at org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:433) * ... 77 common frames omitted * Caused by: java.lang.IllegalArgumentException: No enum constant com.xxx.common.module.enums.StatusEnum.1 * at java.lang.Enum.valueOf(Enum.java:238) * at org.apache.ibatis.type.EnumTypeHandler.getNullableResult(EnumTypeHandler.java:49) * at org.apache.ibatis.type.EnumTypeHandler.getNullableResult(EnumTypeHandler.java:26) * at org.apache.ibatis.type.BaseTypeHandler.getResult(BaseTypeHandler.java:66) * ... 102 common frames omitted
有关于JPA和MybatisPlus的问题。
## 有关于 JPA 和 Mybatis Plus的问题 问题背景描述 1. 确定数据库字段和其所对应的实体类字段一致。例如:DB(mem_name),Class(memName) 2. 用于数据库操作的表,以下简称A表。A表中主键id,名称是id,类型varchar,不为NULL。 3. 我实体类定义如下: ``` // A就是A表对应的实体类 @Data @TableName("A") public class A extends BaseClass { ......... } @Data public abstract class BaseEntity { @TableId(value = "id") private String id ;//id在application.yml中是UUID的 ....... } ``` 问题: 1. 当使用 Mybatis Plus时: 1.1 利用SQL注解,BaseMapper.selectByID,通过Mapper.XML进行查询一行记录,在ServiceImpl的Test测试方法中可以查询出我需要的记录,而通过Controller进行调用Service方法来获取记录,但是SQL已经执行了。就无法查出,但是新增是可以向A表进行插入数据。 为什么通过Controller调用Service的方法,方面内部:selectByID或以上3中方式之一,就无法查询出数据. 2. 当使用 JPA 时: ``` // A就是A表对应的实体类 @Data @Entity @TableName("A") public class A extends BaseClass { @Id @TableId(value = "id") private String id ; ......... } @Data public abstract class BaseEntity { ....... } ``` 2.1 你看的没错,我就是把注解放到原有的MyBatis Plus上面,但是调整id位置了,我放到A类中,同样,可以测试查询,放到tomcat中,就无法用请求->controller->service->repository来查询所需数据? MyBatis-Plus:selectById()无法查询 JAP:findOne(id) 无法查询 都无法放到tomcat中,用请求的方式进行查询,测试都能过! 不明白。求赐教!
关于数据库链接connection是否需要关闭的问题
项目中用的是druid连接池,持久层用的是MyBatis,但是项目中需要用到直接执行SQL语句的需求,于是我通过 @Autowired private SqlSessionFactory sessionFactory; 获取到了sessionFactory,然后通过sessionFactory.openSession()获取到了SqlSession,最后用SqlSession.getConnection();获取到了connection,别问我为什么这么费劲....因为需要用到事务手动管理,到了这一层,我才可以手动控制是否自动提交事务,但是问题来了,现在这种情况下,我如果不主动close这个connection,那么这个connection是否会泄露呢,换种说法,这个connection是否还受druid管理呢?
高分悬赏,求大神指点,SSM项目 dao层测试出错,不知道问题在哪里
# 基于ssm框架开发的项目,dao层测试时发生错误,求大神帮忙指引解决,说不清楚的可以加我q远程协助. 错误代码如下: ``` 五月 10, 2018 12:11:50 下午 org.springframework.context.support.GenericApplicationContext refresh 警告: Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [spring/spring-dao.xml]: Invocation of init method failed; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [D:\MyEclipse\MyClass\o2o Maven Webapp\target\classes\mapper\AreaDao.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error creating document instance. Cause: org.xml.sax.SAXParseException; lineNumber: 2; columnNumber: 47; 文档根元素 "mapper" 必须匹配 DOCTYPE 根 "null"。 五月 10, 2018 12:11:50 下午 org.springframework.test.context.TestContextManager prepareTestInstance 严重: Caught exception while allowing TestExecutionListener [org.springframework.test.context.support.DependencyInjectionTestExecutionListener@77b52d12] to prepare test instance [com.imooc.o2o.dao.AreaDaoTest@4de4b452] java.lang.IllegalStateException: Failed to load ApplicationContext at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:124) at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:83) at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:117) at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83) at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:230) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:228) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:287) at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:289) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:247) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94) at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70) at org.junit.runners.ParentRunner.run(ParentRunner.java:363) at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191) at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86) at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:678) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382) at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192) Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [spring/spring-dao.xml]: Invocation of init method failed; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [D:\MyEclipse\MyClass\o2o Maven Webapp\target\classes\mapper\AreaDao.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error creating document instance. Cause: org.xml.sax.SAXParseException; lineNumber: 2; columnNumber: 47; 文档根元素 "mapper" 必须匹配 DOCTYPE 根 "null"。 at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1628) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:742) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:866) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:542) at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:128) at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:60) at org.springframework.test.context.support.AbstractDelegatingSmartContextLoader.delegateLoading(AbstractDelegatingSmartContextLoader.java:108) at org.springframework.test.context.support.AbstractDelegatingSmartContextLoader.loadContext(AbstractDelegatingSmartContextLoader.java:251) at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:98) at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:116) ... 25 more Caused by: org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [D:\MyEclipse\MyClass\o2o Maven Webapp\target\classes\mapper\AreaDao.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error creating document instance. Cause: org.xml.sax.SAXParseException; lineNumber: 2; columnNumber: 47; 文档根元素 "mapper" 必须匹配 DOCTYPE 根 "null"。 at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:523) at org.mybatis.spring.SqlSessionFactoryBean.afterPropertiesSet(SqlSessionFactoryBean.java:380) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1687) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1624) ... 40 more Caused by: org.apache.ibatis.builder.BuilderException: Error creating document instance. Cause: org.xml.sax.SAXParseException; lineNumber: 2; columnNumber: 47; 文档根元素 "mapper" 必须匹配 DOCTYPE 根 "null"。 at org.apache.ibatis.parsing.XPathParser.createDocument(XPathParser.java:259) at org.apache.ibatis.parsing.XPathParser.<init>(XPathParser.java:125) at org.apache.ibatis.builder.xml.XMLMapperBuilder.<init>(XMLMapperBuilder.java:78) at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:520) ... 43 more Caused by: org.xml.sax.SAXParseException; lineNumber: 2; columnNumber: 47; 文档根元素 "mapper" 必须匹配 DOCTYPE 根 "null"。 at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:203) at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.error(ErrorHandlerWrapper.java:134) at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:396) at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:327) at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:284) at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.rootElementSpecified(XMLDTDValidator.java:1599) at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.handleStartElement(XMLDTDValidator.java:1877) at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.startElement(XMLDTDValidator.java:742) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(XMLDocumentFragmentScannerImpl.java:1359) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$ContentDriver.scanRootElementHook(XMLDocumentScannerImpl.java:1289) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:3132) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(XMLDocumentScannerImpl.java:852) at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:602) at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:505) at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:841) at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:770) at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:141) at com.sun.org.apache.xerces.internal.parsers.DOMParser.parse(DOMParser.java:243) at com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderImpl.parse(DocumentBuilderImpl.java:339) at org.apache.ibatis.parsing.XPathParser.createDocument(XPathParser.java:257) ... 46 more ``` # spring-dao.xml配置文件代码如下: ``` <?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" 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"> <!-- 配置整合mybatis过程 --> <!-- 1.配置数据库相关参数properties的属性:${url} --> <context:property-placeholder location="classpath:jdbc.properties"/> <!-- 2.数据库连接池 --> <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <!-- 配置连接池属性 --> <property name="driverClass" value="${jdbc.driver}" /> <property name="jdbcUrl" value="${jdbc.url}" /> <property name="user" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <!-- c3p0连接池的私有属性 --> <property name="maxPoolSize" value="30" /> <property name="minPoolSize" value="10" /> <!-- 关闭连接后不自动commit --> <property name="autoCommitOnClose" value="false" /> <!-- 获取连接超时时间 --> <property name="checkoutTimeout" value="10000" /> <!-- 当获取连接失败重试次数 --> <property name="acquireRetryAttempts" value="2" /> </bean> <!-- 3.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" /> <!-- 配置MyBaties全局配置文件:mybatis-config.xml --> <property name="configLocation" value="classpath:mybatis-config.xml" /> <!-- 扫描entity包 使用别名 --> <property name="typeAliasesPackage" value="com.imooc.o2o.entity" /> <!-- 扫描sql配置文件:mapper需要的xml文件 --> <property name="mapperLocations" value="classpath:mapper/*.xml" /> </bean> <!-- 4.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.imooc.o2o.dao" /> </bean> </beans> ``` 知道怎么解决的直接加我Q吧,万分感谢,472562424
关于多表联查的缓存问题,使用什么样的技术可以解决?
最近在做一个后台的权限管理系统,使用了shiro来进行权限的空值,所以每次登陆的时候都会到数据库里查找当前用户所对应的角色和权限,每次都要通过从账号到用户,到角色,到权限的查询,中间还有两张关联表,所以很耗费时间 上面要求让我做一个缓存,将查询结果缓存起来,同时要做到每个角色或者用户的更改缓存中的数据也需要清除或更改 首先我想的是mybatis的二级缓存应该是不能用,每个缓存是以namespace为单位的,用户表,角色表,角色用户关联表,无论我把sql写在那个namespace下,另一张表中数据的更改并不会影响的这边,所以会出现数据错误的情况...后来上边给了我一个文档,是spring和ehcache结合的使用,我查看了之后发现他们其实有着相同的地方,他是利用了aop的思想,在执行查询方法的时候查询是否有缓存,如果没有就利用反射的原理将该方法的全名做为cache的键,将查询结果作为值保存在cache中;然后在执行增删改的时候也是利用反射的原理获取该方法的所在的类,然后清除缓存中所有以该类名开头的缓存..这样也就是说我在用户的service下执行了角色的查询,那么我只有在操作该类下的增删改方法的时候才能清除缓存,然而我如果对角色进行了更改完全不会影响到这边的缓存操作。。除非我将用户角色所有的方法全部放在一个server下,不然缓存是会出现错误的 希望有朋友帮我解决这个问题,我是新手,也不了解redis,不知道能否解决这样的问题?求帮助。。
求大神指点,SSM项目 dao层测试出错,不知道问题在哪里
# 基于ssm框架开发的项目,dao层测试时发生错误,求大神帮忙指引解决,说不清楚的可以加我q远程协助. ```五月 10, 2018 12:11:50 下午 org.springframework.context.support.GenericApplicationContext refresh 警告: Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [spring/spring-dao.xml]: Invocation of init method failed; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [D:\MyEclipse\MyClass\o2o Maven Webapp\target\classes\mapper\AreaDao.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error creating document instance. Cause: org.xml.sax.SAXParseException; lineNumber: 2; columnNumber: 47; 文档根元素 "mapper" 必须匹配 DOCTYPE 根 "null"。 五月 10, 2018 12:11:50 下午 org.springframework.test.context.TestContextManager prepareTestInstance 严重: Caught exception while allowing TestExecutionListener [org.springframework.test.context.support.DependencyInjectionTestExecutionListener@77b52d12] to prepare test instance [com.imooc.o2o.dao.AreaDaoTest@4de4b452] java.lang.IllegalStateException: Failed to load ApplicationContext # spring-dao.xml配置如下 ``` <?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" 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"> <!-- 配置整合mybatis过程 --> <!-- 1.配置数据库相关参数properties的属性:${url} --> <context:property-placeholder location="classpath:jdbc.properties"/> <!-- 2.数据库连接池 --> <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"> <!-- 配置连接池属性 --> <property name="driverClass" value="${jdbc.driver}" /> <property name="jdbcUrl" value="${jdbc.url}" /> <property name="user" value="${jdbc.username}" /> <property name="password" value="${jdbc.password}" /> <!-- c3p0连接池的私有属性 --> <property name="maxPoolSize" value="30" /> <property name="minPoolSize" value="10" /> <!-- 关闭连接后不自动commit --> <property name="autoCommitOnClose" value="false" /> <!-- 获取连接超时时间 --> <property name="checkoutTimeout" value="10000" /> <!-- 当获取连接失败重试次数 --> <property name="acquireRetryAttempts" value="2" /> </bean> <!-- 3.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" /> <!-- 配置MyBaties全局配置文件:mybatis-config.xml --> <property name="configLocation" value="classpath:mybatis-config.xml" /> <!-- 扫描entity包 使用别名 --> <property name="typeAliasesPackage" value="com.imooc.o2o.entity" /> <!-- 扫描sql配置文件:mapper需要的xml文件 --> <property name="mapperLocations" value="classpath:mapper/*.xml" /> </bean> <!-- 4.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.imooc.o2o.dao" /> </bean> </beans> ```
JNDI破坏双亲加载机制的一些疑问
import java.sql.Connection; Context ctx = new InitialContext(); DataSource ds = (DataSource) ctx.lookup("java:comp/env/jndi/mybatis"); Connection conn = ds.getConnection(); 我们知道JNDI,JDBC加载具体生产商实现的服务时,是父类委托子类去加载的,即通过设置线程类加载器去加载,如此破坏了双亲加载机制。 疑问在于: 我们知道不同的类加载加载的类之间是无法发生关系的(继承,实现,依赖,强制转换等)。如Class A被自定义ClassloaderA和自定义ClassloaderB加载,然后实例化两个对象objA和objB,那么objA(loaded by ClassloaderA) instance of ClassA(loaded by ClassloaderB)结果为false. 以tomcat实现JNDI为例,这段代码里,import java.sql.Connection 这个Connection接口是rt.jar下边的,按照虚拟机加载原理,是由bootstrap类加载器加载的,我们看不到。 而Connection conn = ds.getConnection(); 这里获取的Connection实现类是tomcat自己定义的类加载器加载的(org.apache.catalina.loader.StandardClassLoader)。即Connection接口和实现类是由不同的类加载器加载的,但是他们仍然可以赋值成功,这一点很奇怪,请高手指点迷津。
javaweb小项目,在写完登录功能时设置断点查看程序运行状况时得到的结果和直接运行得到的结果不一样???
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