mybatis sql里获取不到查询的值

<select id="selectAll" parameterType="com.xxx.entity.BiReportsTemplate" resultMap="BaseResultMap" > 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 <if test="templatename != null" > and brt.templateName = #{templatename,jdbcType=VARCHAR} </if> order by brt.rtid </select> sql如上， <if test="templatename != null" > and brt.templateName = #{templatename,jdbcType=VARCHAR} </if> 获取不到templatename值什么原因哦？？？

Mybatis 不能获取sqlserver序列

### SQL: SELECT NEXT VALUE FOR sqp_decodenum ### Cause: com.microsoft.sqlserver.jdbc.SQLServerException: 对象名 'sqp_decodenum' 无效。 在SQLServer 可以查询到序列值，Mybatis 报错

通过mybatis拦截器获取到执行的sql语句,如果我的service层报错,怎么才能让拦截器中的sql语句不保存下来

问题描述:程序记录每一条增,改,更新sql,其实获取的sql语句是在真正执行前通过拼接方式获得的完整的即将执行的sql语句,但是当service报错时,这些语句还是会记录下来,我想问的是怎么能避免这种情况,当service报错时,mybatis拦截器拦截下来的sql语句不记录

mybatis 多对一但是实体类中获得不到查询的结果

```DEBUG [http-bio-80-exec-2] - <== Total: 1 DEBUG [http-bio-80-exec-2] - Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7a30581e] DEBUG [http-bio-80-exec-2] - Fetched SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7a30581e] from current transaction DEBUG [http-bio-80-exec-2] - ooo Using Connection [com.mysql.jdbc.JDBC4Connection@67df626e] DEBUG [http-bio-80-exec-2] - ==> Preparing: select m.id,u.username as u_user,u.userid as u_id,m.message from message m LEFT JOIN user u on m.user_id=u.userId limit ?,? DEBUG [http-bio-80-exec-2] - ==> Parameters: 0(Integer), 1(Integer) TRACE [http-bio-80-exec-2] - <== Columns: id, u_user, u_id, message TRACE [http-bio-80-exec-2] - <== Row: 2, admin, 21, ajksgbiquldbakj,dgwouidbkaj DEBUG [http-bio-80-exec-2] - <== Total: 1 DEBUG [http-bio-80-exec-2] - Releasing transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7a30581e] [Message [id=2, message=ajksgbiquldbakj,dgwouidbkaj, user=null]] [{"keyword":null,"page":1,"rows":1}]DEBUG [http-bio-80-exec-2] - Transaction synchronization deregistering SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7a30581e] DEBUG [http-bio-80-exec-2] - Transaction synchronization closing SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@7a30581e] [Message [id=2, message=ajksgbiquldbakj,dgwouidbkaj, user=null]] ``` ```//实体类 ```public class Message { private Long id; private String message; private User user; @Override public String toString() { return "Message [id=" + id + ", message=" + message + ", user=" + user + "]"; } } ```//xml文件 <select id="queryForPage" resultMap="BaseResultMap"> select m.id,u.username as u_user,u.userid as u_id,m.message from message m LEFT JOIN user u on m.user_id=u.userId <include refid="where_sql"/> <if test="page!=null"> limit #{start},#{rows} </if> </select> ```//resultMap <resultMap id="BaseResultMap" type="com._520it.com.domain.Message"> <id column="id" jdbcType="BIGINT" property="id" /> <result column="message" jdbcType="VARCHAR" property="message" /> <association property="user" javaType="com._520it.com.domain.User" columnPrefix="u_"> <id column="userid" property="id" /> <result column="username" property="user"/> </association> </resultMap> message 实体类中的user获得不到查询出来的结果

关于Mybatis子查询嵌套问题

直接上Sql代码 ``` SELECT t.*, ( SELECT count( s.un_sid ) FROM un_star s WHERE t.un_pid = s.un_pid AND s.un_uid = #{unUid,jdbcType=INTEGER) ) AS 'skey', ( SELECT count( l.un_lid ) FROM un_like l WHERE t.un_pid = l.un_pid AND l.un_uid = #{unUid,jdbcType=INTEGER) ) AS 'lkey' FROM ( SELECT a.*, b.un_uname, b.un_uid, b.un_upic FROM `un_pic` a, `un_user` b WHERE b.un_uid = a.un_plinkid AND a.un_pstatus = 0 ORDER BY a.un_pid DESC ) t ``` 运行的话会报错如下图  我把 ( SELECT count( s.un_sid ) FROM un_star s WHERE t.un_pid = s.un_pid AND s.un_uid = 3) AS 'skey', ( SELECT count( l.un_lid ) FROM un_like l WHERE t.un_pid = l.un_pid AND l.un_uid = 3) ) AS 'lkey' 这两句的 #{}里面 直接换成数字ID就可以正常通过，就很纳闷，怎么才能把UID传递进去呢？ 目前的mybatis里是这样写的 ``` <select id="selectUserHomePic" resultMap="QueryPicList" parameterType="java.lang.Integer" > SELECT t.*, (SELECT count( s.un_sid ) FROM un_star s WHERE t.un_pid = s.un_pid AND s.un_uid = #{unUid,jdbcType=INTEGER)) AS 'skey', (SELECT count( l.un_lid ) FROM un_like l WHERE t.un_pid = l.un_pid AND l.un_uid = #{unUid,jdbcType=INTEGER)) AS 'lkey' FROM ( SELECT a.*, b.un_uname, b.un_uid, b.un_upic FROM `un_pic` a, `un_user` b WHERE b.un_uid = a.un_plinkid AND a.un_pstatus = 0 ORDER BY a.un_pid DESC ) t </select> ``` 求助 已经解决了该问题了！请遇到此类 链接多个数据表，并且传递参数的时候，要将参数放在 最外层的where去 传递， 括号()里面的select语句传递参数是获取不到的 如下 ``` <select id="selectUserHomePic" resultMap="QueryPicList" parameterType="java.lang.Integer" > SELECT t.*, (SELECT count( s.un_sid ) FROM un_star s WHERE t.un_pid = s.un_pid AND s.un_uid = b.un_uid) AS 'skey', (SELECT count( l.un_lid ) FROM un_like l WHERE t.un_pid = l.un_pid AND l.un_uid = b.un_uid ) AS 'lkey' FROM ( SELECT a.*, b.un_uname, b.un_uid, b.un_upic FROM `un_pic` a, `un_user` b WHERE b.un_uid = a.un_plinkid AND a.un_pstatus = 0 ORDER BY a.un_pid DESC ) t , `un_user ` b where b.un_uid = #{unUid,jdbcType=INTEGER) </select> ``` 将（）内的 #{unUid,jdbcType=INTEGER) 移植到下面去

mybatis中mapper配置问题

第一次创建，报一下这些错误，求解决！求解决！不知道usermapper哪里出问题 D:\Java\jdk1.8.0_172\bin\java.exe "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2018.1.5\lib\idea_rt.jar=58476:C:\Program Files\JetBrains\IntelliJ IDEA 2018.1.5\bin" -Dfile.encoding=UTF-8 -classpath D:\Java\jdk1.8.0_172\jre\lib\charsets.jar;D:\Java\jdk1.8.0_172\jre\lib\deploy.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\access-bridge-64.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\cldrdata.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\dnsns.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\jaccess.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\jfxrt.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\localedata.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\nashorn.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\sunec.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\sunjce_provider.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\sunmscapi.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\sunpkcs11.jar;D:\Java\jdk1.8.0_172\jre\lib\ext\zipfs.jar;D:\Java\jdk1.8.0_172\jre\lib\javaws.jar;D:\Java\jdk1.8.0_172\jre\lib\jce.jar;D:\Java\jdk1.8.0_172\jre\lib\jfr.jar;D:\Java\jdk1.8.0_172\jre\lib\jfxswt.jar;D:\Java\jdk1.8.0_172\jre\lib\jsse.jar;D:\Java\jdk1.8.0_172\jre\lib\management-agent.jar;D:\Java\jdk1.8.0_172\jre\lib\plugin.jar;D:\Java\jdk1.8.0_172\jre\lib\resources.jar;D:\Java\jdk1.8.0_172\jre\lib\rt.jar;D:\workplace\webssm\target\classes;D:\mavenRepository\jstl\jstl\1.2\jstl-1.2.jar;D:\mavenRepository\javax\javaee-api\7.0\javaee-api-7.0.jar;D:\mavenRepository\com\sun\mail\javax.mail\1.5.0\javax.mail-1.5.0.jar;D:\mavenRepository\javax\activation\activation\1.1\activation-1.1.jar;D:\mavenRepository\org\mybatis\mybatis\3.3.0\mybatis-3.3.0.jar;D:\mavenRepository\mysql\mysql-connector-java\5.1.29\mysql-connector-java-5.1.29.jar;D:\mavenRepository\commons-dbcp\commons-dbcp\1.2.2\commons-dbcp-1.2.2.jar;D:\mavenRepository\commons-pool\commons-pool\1.3\commons-pool-1.3.jar;D:\mavenRepository\com\alibaba\fastjson\1.1.41\fastjson-1.1.41.jar;D:\mavenRepository\log4j\log4j\1.2.17\log4j-1.2.17.jar;D:\mavenRepository\org\slf4j\slf4j-api\1.7.18\slf4j-api-1.7.18.jar;D:\mavenRepository\org\slf4j\slf4j-log4j12\1.7.18\slf4j-log4j12-1.7.18.jar;D:\mavenRepository\org\codehaus\jackson\jackson-mapper-asl\1.9.13\jackson-mapper-asl-1.9.13.jar;D:\mavenRepository\org\codehaus\jackson\jackson-core-asl\1.9.13\jackson-core-asl-1.9.13.jar;D:\mavenRepository\com\fasterxml\jackson\core\jackson-core\2.8.0\jackson-core-2.8.0.jar;D:\mavenRepository\com\fasterxml\jackson\core\jackson-databind\2.8.0\jackson-databind-2.8.0.jar;D:\mavenRepository\com\fasterxml\jackson\core\jackson-annotations\2.8.0\jackson-annotations-2.8.0.jar;D:\mavenRepository\commons-fileupload\commons-fileupload\1.3.1\commons-fileupload-1.3.1.jar;D:\mavenRepository\commons-io\commons-io\2.4\commons-io-2.4.jar;D:\mavenRepository\commons-codec\commons-codec\1.9\commons-codec-1.9.jar com.controller.test Exception in thread "main" org.apache.ibatis.exceptions.PersistenceException: ### Error building SqlSession. ### The error may exist in com/mapper/UserMapper.java (best guess) ### Cause: org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error creating document instance. Cause: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 43; 文档根元素 "mapper" 必须匹配 DOCTYPE 根 "null"。 at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30) at org.apache.ibatis.session.SqlSessionFactoryBuilder.build(SqlSessionFactoryBuilder.java:54) at org.apache.ibatis.session.SqlSessionFactoryBuilder.build(SqlSessionFactoryBuilder.java:38) at com.controller.test.main(test.java:25) Caused by: org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error creating document instance. Cause: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 43; 文档根元素 "mapper" 必须匹配 DOCTYPE 根 "null"。 at org.apache.ibatis.builder.xml.XMLConfigBuilder.parseConfiguration(XMLConfigBuilder.java:115) at org.apache.ibatis.builder.xml.XMLConfigBuilder.parse(XMLConfigBuilder.java:95) at org.apache.ibatis.session.SqlSessionFactoryBuilder.build(SqlSessionFactoryBuilder.java:52) ... 2 more Caused by: org.apache.ibatis.builder.BuilderException: Error creating document instance. Cause: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 43; 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.apache.ibatis.builder.xml.XMLMapperBuilder.<init>(XMLMapperBuilder.java:73) at org.apache.ibatis.builder.annotation.MapperAnnotationBuilder.loadXmlResource(MapperAnnotationBuilder.java:166) at org.apache.ibatis.builder.annotation.MapperAnnotationBuilder.parse(MapperAnnotationBuilder.java:118) at org.apache.ibatis.binding.MapperRegistry.addMapper(MapperRegistry.java:72) at org.apache.ibatis.session.Configuration.addMapper(Configuration.java:671) at org.apache.ibatis.builder.xml.XMLConfigBuilder.mapperElement(XMLConfigBuilder.java:348) at org.apache.ibatis.builder.xml.XMLConfigBuilder.parseConfiguration(XMLConfigBuilder.java:113) ... 4 more Caused by: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 43; 文档根元素 "mapper" 必须匹配 DOCTYPE 根 "null"。 <mapper namespace="com.mapper.UserMapper"> <resultMap type="com.pojo.User" id="userResultMap"> <id property="id" colum="id"/> <result property="username" column="username"/> <result property="sex" column="sex"/> <result property="age" column="age"/> <result property="loginname" column="loginname"/> <result property="password" column="password"/> <result property="phone" column="phone"/> <result property="address" column="address"/> <!-- 一对多关联映射--> <collection property="orders" javaType="ArrayList" column="id" ofType="com.pojo.User" select="com.mapper.OrderMapper.selectOrderByUserId" fetchType="lazy"> <id property="id" colum="id"></id> <result property="code" column="code"></result> <result property="total" column="total"></result> </collection> </resultMap> <select id="selectUserById" parameterType="int" resultMap="userResultMap"> SELECT * FROM user WHERE id = #{id} </select> </mapper> package com.controller; import com.mapper.OrderMapper; import com.mapper.UserMapper; import com.pojo.Order; import com.pojo.User; import org.apache.ibatis.io.Resources; import org.apache.ibatis.session.*; //import org.mybatis.spring.SqlSessionFactoryBean; //import org.springframework.aop.scope.ScopedProxyUtils; import java.io.IOException; //import java.io.InputStream; import java.io.Reader; import java.util.List; public class test { public static void main(String[] args) throws IOException { //读取mybatis-config.xml文件 //InputStream inputStream= Resources.getResourceAsStream("mybatis-config.xml"); Reader reader=Resources.getResourceAsReader("mybatis-config.xml"); //初始化mybatis，创建sqlsessionfactory类的实例 SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader); //创建Session实例 SqlSession session=sqlSessionFactory.openSession(); test t=new test(); t.testSelectUserById(session); t.testSelectOrderById(session); session.commit(); session.close(); } //测试一对多关系 public void testSelectUserById(SqlSession session){ //获得usermapper接口的代理对象 UserMapper um=session.getMapper(UserMapper.class); //调用selectUserById方法 User user=um.selectUserById(1); //查询user的对象信息 System.out.println(user.getId()+""+user.getUsername()); List<Order> orders=user.getOrders(); for (Order order:orders ) { System.out.println(order); } } //测试多对多的关系，查询订单Order的时候级联查询订单的商品 public void testSelectOrderById(SqlSession session){ //获得OrderMapper接口的代理对象 OrderMapper om=session.getMapper(OrderMapper.class); //调用selectOrderById方法 Order order=om.selectOrderById(2); //查看查询到的信息 System.out.println(order.getId()+""+order.getCode()+""+order.getTotal()); User user=order.getUser(); System.out.println(user); } }

mybatis传值到XML里面，为什么参数类型是HashMap可以获取到参数值，Map就不行？

  [ [ 第一二张图是别人写的代码，三四张是我写的代码，一开始我也像他那样在XML文件里面传入的参数配置为java.util.Map,虽然能正常运行，但是却不能传入参数，打印出来的SQL，传入的参数显示为“？”当我把传入的参数类型改为java.util.HashMap又能看到传入的参数为正常，请问为什么，我们代码基本都是一样的啊。

Mybatis小练习 报错 求大神指导，信息详尽

# 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

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基于springmvc+mybatis的登录表单提交后404

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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： 

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？

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求大神指点,SSM项目 dao层测试出错,不知道问题在哪里

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JNDI破坏双亲加载机制的一些疑问

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