MyBatis中怎么自定义typeHandler

本篇文章为大家展示了MyBatis中怎么自定义typeHandler，内容简明扼要并且容易理解，绝对能使你眼前一亮，通过这篇文章的详细介绍希望你能有所收获。

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首先编写调度的处理类

package com.ming.MyBatis;


import org.apache.ibatis.type.JdbcType;
import org.apache.ibatis.type.TypeHandler;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;

import java.sql.CallableStatement;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class StringTypeHandler implements TypeHandler {
 private static Logger logger = LogManager.getLogger();

 /**
  * 对预编译的Sql语句进行设置的时候,
  * @param ps
  * @param i
  * @param parameter
  * @param jdbcType
  * @throws SQLException
  */
 @Override
 public void setParameter(PreparedStatement ps, int i, String parameter, JdbcType jdbcType) throws SQLException {
  logger.info("使用TypeHandler");
  // 设置预编译的sql对象,的string
  ps.setString(i, parameter);
 }

 /**
  * 获得结果的时候,获取到列名的时候,调度此方法
  * @param rs
  * @param columnName
  * @return
  * @throws SQLException
  */
 @Override
 public String getResult(ResultSet rs, String columnName) throws SQLException {
  logger.info("使用自定义类型,结果获取列名字符串");
  return rs.getString(columnName);
 }

 /**
  * 获取结果集中的index
  * @param rs
  * @param columnIndex
  * @return
  * @throws SQLException
  */
 @Override
 public String getResult(ResultSet rs, int columnIndex) throws SQLException {
  logger.info("在结果集中获取columnIndex");
  return rs.getString(columnIndex);
 }

 /**
  * 获取结果集中的下标对应的字符串
  * @param cs
  * @param columnIndex
  * @return
  * @throws SQLException
  */
 @Override
 public String getResult(CallableStatement cs, int columnIndex) throws SQLException {
  logger.info("结果集中,下标获取到字符串");
  return cs.getString(columnIndex);
 }
}

再次编写配置文件

传入数据库的为的VARCHAR类型,javaType类型为string类型,调度的类为com.ming.MyBatis.StringTypeHandler

修改映射文件,说明那些需要对结果进行修改

 
 
 
 
 
 
 
 
 
 
 
 
 SELECT id, role_name, note FROM t_role4 WHERE id = #{id}
 
 

其中传入的参数为int类型,由于结果中mybatis没有int类型,对应的是INTEGER类型,在MySQL中两者类型相同,所以修改如上所示,表类型

书写index.jsp

<%@ page import="org.apache.ibatis.session.SqlSession" %>
<%@ page import="com.ming.Util.SqlSessionFactoryUtil" %>
<%@ page import="com.ming.MyBatis.POJO.RoleMapper" %>
<%@ page import="com.ming.MyBatis.POJO.Role" %>


Hello World!

<%
  long startTime = System.currentTimeMillis(); //获取开始时间
  SqlSession sqlSession = null;
  Role role = null;
  for(int i = 0; i < 10; i++) {
    try {
      sqlSession = SqlSessionFactoryUtil.openSqlSesion();
      RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);
      role = roleMapper.getRole(100);
      sqlSession.commit();
    } catch (Exception e) {
      e.printStackTrace();
      sqlSession.rollback();
    } finally {
      if (sqlSession != null) {
        sqlSession.close();
      }
    }
  }
  long endTime = System.currentTimeMillis(); //获取结束时间

%>
<%=role.getNote()%>

已经查询成功

查看日志文件,日志文件已经输出相关信息

2019-04-13 05:03:33.181 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:136) - Opening JDBC Connection
2019-04-13 05:03:33.181 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:397) - Checked out connection 197673257 from pool.
2019-04-13 05:03:33.182 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.setDesiredAutoCommit(JdbcTransaction.java:100) - Setting autocommit to false on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.235 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Preparing: SELECT id, role_name, note FROM t_role4 WHERE id = ? 
2019-04-13 05:03:33.236 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Parameters: 100(Integer)
2019-04-13 05:03:33.275 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.276 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.277 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - <==   Total: 1
2019-04-13 05:03:33.277 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.resetAutoCommit(JdbcTransaction.java:122) - Resetting autocommit to true on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.312 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.close(JdbcTransaction.java:90) - Closing JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.312 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.pushConnection(PooledDataSource.java:362) - Returned connection 197673257 to pool.
2019-04-13 05:03:33.313 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:136) - Opening JDBC Connection
2019-04-13 05:03:33.314 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:397) - Checked out connection 197673257 from pool.
2019-04-13 05:03:33.314 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.setDesiredAutoCommit(JdbcTransaction.java:100) - Setting autocommit to false on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.346 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Preparing: SELECT id, role_name, note FROM t_role4 WHERE id = ? 
2019-04-13 05:03:33.348 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Parameters: 100(Integer)
2019-04-13 05:03:33.386 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.390 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.391 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - <==   Total: 1
2019-04-13 05:03:33.395 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.resetAutoCommit(JdbcTransaction.java:122) - Resetting autocommit to true on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.442 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.close(JdbcTransaction.java:90) - Closing JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.443 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.pushConnection(PooledDataSource.java:362) - Returned connection 197673257 to pool.
2019-04-13 05:03:33.443 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:136) - Opening JDBC Connection
2019-04-13 05:03:33.444 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:397) - Checked out connection 197673257 from pool.
2019-04-13 05:03:33.444 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.setDesiredAutoCommit(JdbcTransaction.java:100) - Setting autocommit to false on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.479 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Preparing: SELECT id, role_name, note FROM t_role4 WHERE id = ? 
2019-04-13 05:03:33.480 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Parameters: 100(Integer)
2019-04-13 05:03:33.518 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.519 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.520 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - <==   Total: 1
2019-04-13 05:03:33.520 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.resetAutoCommit(JdbcTransaction.java:122) - Resetting autocommit to true on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.556 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.close(JdbcTransaction.java:90) - Closing JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.557 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.pushConnection(PooledDataSource.java:362) - Returned connection 197673257 to pool.
2019-04-13 05:03:33.558 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:136) - Opening JDBC Connection
2019-04-13 05:03:33.558 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:397) - Checked out connection 197673257 from pool.
2019-04-13 05:03:33.558 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.setDesiredAutoCommit(JdbcTransaction.java:100) - Setting autocommit to false on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.591 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Preparing: SELECT id, role_name, note FROM t_role4 WHERE id = ? 
2019-04-13 05:03:33.592 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Parameters: 100(Integer)
2019-04-13 05:03:33.638 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.639 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.640 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - <==   Total: 1
2019-04-13 05:03:33.640 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.resetAutoCommit(JdbcTransaction.java:122) - Resetting autocommit to true on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.676 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.close(JdbcTransaction.java:90) - Closing JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.677 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.pushConnection(PooledDataSource.java:362) - Returned connection 197673257 to pool.
2019-04-13 05:03:33.677 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:136) - Opening JDBC Connection
2019-04-13 05:03:33.677 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:397) - Checked out connection 197673257 from pool.
2019-04-13 05:03:33.677 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.setDesiredAutoCommit(JdbcTransaction.java:100) - Setting autocommit to false on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.711 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Preparing: SELECT id, role_name, note FROM t_role4 WHERE id = ? 
2019-04-13 05:03:33.712 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Parameters: 100(Integer)
2019-04-13 05:03:33.747 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.748 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.748 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - <==   Total: 1
2019-04-13 05:03:33.749 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.resetAutoCommit(JdbcTransaction.java:122) - Resetting autocommit to true on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.780 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.close(JdbcTransaction.java:90) - Closing JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.780 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.pushConnection(PooledDataSource.java:362) - Returned connection 197673257 to pool.
2019-04-13 05:03:33.781 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:136) - Opening JDBC Connection
2019-04-13 05:03:33.781 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:397) - Checked out connection 197673257 from pool.
2019-04-13 05:03:33.781 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.setDesiredAutoCommit(JdbcTransaction.java:100) - Setting autocommit to false on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.830 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Preparing: SELECT id, role_name, note FROM t_role4 WHERE id = ? 
2019-04-13 05:03:33.831 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Parameters: 100(Integer)
2019-04-13 05:03:33.868 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.870 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.870 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - <==   Total: 1
2019-04-13 05:03:33.872 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.resetAutoCommit(JdbcTransaction.java:122) - Resetting autocommit to true on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.913 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.close(JdbcTransaction.java:90) - Closing JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.914 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.pushConnection(PooledDataSource.java:362) - Returned connection 197673257 to pool.
2019-04-13 05:03:33.914 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:136) - Opening JDBC Connection
2019-04-13 05:03:33.915 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:397) - Checked out connection 197673257 from pool.
2019-04-13 05:03:33.915 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.setDesiredAutoCommit(JdbcTransaction.java:100) - Setting autocommit to false on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:33.956 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Preparing: SELECT id, role_name, note FROM t_role4 WHERE id = ? 
2019-04-13 05:03:33.957 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Parameters: 100(Integer)
2019-04-13 05:03:33.994 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.994 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:33.995 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - <==   Total: 1
2019-04-13 05:03:33.995 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.resetAutoCommit(JdbcTransaction.java:122) - Resetting autocommit to true on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:34.029 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.close(JdbcTransaction.java:90) - Closing JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:34.029 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.pushConnection(PooledDataSource.java:362) - Returned connection 197673257 to pool.
2019-04-13 05:03:34.030 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:136) - Opening JDBC Connection
2019-04-13 05:03:34.030 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:397) - Checked out connection 197673257 from pool.
2019-04-13 05:03:34.030 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.setDesiredAutoCommit(JdbcTransaction.java:100) - Setting autocommit to false on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:34.095 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Preparing: SELECT id, role_name, note FROM t_role4 WHERE id = ? 
2019-04-13 05:03:34.097 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Parameters: 100(Integer)
2019-04-13 05:03:34.133 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:34.133 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:34.134 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - <==   Total: 1
2019-04-13 05:03:34.134 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.resetAutoCommit(JdbcTransaction.java:122) - Resetting autocommit to true on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:34.168 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.close(JdbcTransaction.java:90) - Closing JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:34.169 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.pushConnection(PooledDataSource.java:362) - Returned connection 197673257 to pool.
2019-04-13 05:03:34.170 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:136) - Opening JDBC Connection
2019-04-13 05:03:34.170 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:397) - Checked out connection 197673257 from pool.
2019-04-13 05:03:34.171 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.setDesiredAutoCommit(JdbcTransaction.java:100) - Setting autocommit to false on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:34.214 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Preparing: SELECT id, role_name, note FROM t_role4 WHERE id = ? 
2019-04-13 05:03:34.215 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Parameters: 100(Integer)
2019-04-13 05:03:34.252 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:34.252 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:34.253 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - <==   Total: 1
2019-04-13 05:03:34.254 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.resetAutoCommit(JdbcTransaction.java:122) - Resetting autocommit to true on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:34.291 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.close(JdbcTransaction.java:90) - Closing JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:34.291 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.pushConnection(PooledDataSource.java:362) - Returned connection 197673257 to pool.
2019-04-13 05:03:34.292 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.openConnection(JdbcTransaction.java:136) - Opening JDBC Connection
2019-04-13 05:03:34.292 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.popConnection(PooledDataSource.java:397) - Checked out connection 197673257 from pool.
2019-04-13 05:03:34.292 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.setDesiredAutoCommit(JdbcTransaction.java:100) - Setting autocommit to false on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:34.336 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Preparing: SELECT id, role_name, note FROM t_role4 WHERE id = ? 
2019-04-13 05:03:34.337 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - ==> Parameters: 100(Integer)
2019-04-13 05:03:34.379 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:34.380 [INFO ] com.ming.MyBatis.StringTypeHandler.getResult(StringTypeHandler.java:48) - 使用自定义类型,结果获取列名字符串
2019-04-13 05:03:34.380 [DEBUG] org.apache.ibatis.logging.jdbc.BaseJdbcLogger.debug(BaseJdbcLogger.java:143) - <==   Total: 1
2019-04-13 05:03:34.381 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.resetAutoCommit(JdbcTransaction.java:122) - Resetting autocommit to true on JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:34.415 [DEBUG] org.apache.ibatis.transaction.jdbc.JdbcTransaction.close(JdbcTransaction.java:90) - Closing JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@bc84129]
2019-04-13 05:03:34.415 [DEBUG] org.apache.ibatis.datasource.pooled.PooledDataSource.pushConnection(PooledDataSource.java:362) - Returned connection 197673257 to pool.

上述内容就是MyBatis中怎么自定义typeHandler，你们学到知识或技能了吗？如果还想学到更多技能或者丰富自己的知识储备，欢迎关注创新互联行业资讯频道。