总结一下工具类备用：
MybatisUtil：
package com.macw.util; import java.io.IOException; import java.io.InputStream; import org.apache.ibatis.io.Resources; import org.apache.ibatis.session.SqlSession; import org.apache.ibatis.session.SqlSessionFactory; import org.apache.ibatis.session.SqlSessionFactoryBuilder; public class MyBatisUtils { private static SqlSessionFactory factory = null; private static ThreadLocal<SqlSession> tl = new ThreadLocal<SqlSession>(); static { // 1 读取配置文件 config.xml InputStream in = null; try { in = Resources.getResourceAsStream("mybatis-config.xml"); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); throw new RuntimeException(e); } // 2 创建SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in); } public static SqlSession openSession() { // 3 创建SqlSession SqlSession sqlSession = tl.get(); if (sqlSession == null) { sqlSession = factory.openSession(); tl.set(sqlSession); } return sqlSession; } public static void close(SqlSession sqlSession) { if (sqlSession != null) { tl.remove(); sqlSession.close(); } } }所用到的mybatis-config.xml文件：
<?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> <properties resource="druid.properties"></properties> <!-- <settings> 打印SQL语句 <setting name="logImpl" value="LOG4J"/> </settings> --> <!-- 给包起别名 --> <typeAliases> <typeAlias type="com.macw.entity.User" alias="user"/> <package name="com.macw.entity"/> </typeAliases> <environments default="oracle"> <environment id="oracle"> <transactionManager type="JDBC"></transactionManager> <dataSource type="POOLED"> <property name="driver" value="${DriverClassName}"/> <property name="url" value="${url}"/> <property name="username" value="${username}"/> <property name="password" value="${password}"/> <!-- <property name="initialSize" value="${initialSize}"/> <property name="maxActive" value="${maxActive}"/> <property name="maxWait" value="${maxWait}"/> --> </dataSource> </environment> </environments> <!-- mapper文件的映射 --> <mappers> <mapper resource="com/macw/dao/mapper/UserMapper.xml"/> </mappers> </configuration>上面xml所用到的druid.properties文件： 连接Oracle数据库的配置文件
DriverClassName=oracle.jdbc.OracleDriver url=jdbc:oracle:thin:@localhost:1521:xe username=macw password=macw initialSize=10 maxActive=50 maxWait=60000Mybatis工具类在ServiceImpl类下的使用：
package com.macw.service.impl; import java.util.List; import org.apache.ibatis.session.SqlSession; import com.macw.dao.OrderDao; import com.macw.entity.Order; import com.macw.service.OrderService; import com.macw.util.MyBatisUtils; /** * @author 超伟 * @2019年7月16日 上午10:41:20 * @博客：https://blog.csdn.net/MacWx */ public class OrderServiceImpl implements OrderService { private OrderDao dao; /* (non-Javadoc) * @see com.macw.service.OrderService#insertOrder(com.macw.entity.Order) */ @Override public void insertOrder(Order order) { // TODO Auto-generated method stub SqlSession sqlSession = MyBatisUtils.openSession(); dao = sqlSession.getMapper(OrderDao.class); try { dao.insertOrder(order); sqlSession.commit(); } catch (Exception e) { // TODO: handle exception sqlSession.rollback(); } finally { MyBatisUtils.close(sqlSession); } } }log4j.properties：
log4j.rootLogger=DEBUG, stdout # SqlMap logging configuration... log4j.logger.com.ibatis=DEBUG log4j.logger.com.ibatis.common.jdbc.SimpleDataSource=DEBUG log4j.logger.com.ibatis.sqlmap.engine.cache.CacheModel=DEBUG log4j.logger.com.ibatis.sqlmap.engine.impl.SqlMapClientImpl=DEBUG log4j.logger.com.ibatis.sqlmap.engine.builder.xml.SqlMapParser=DEBUG log4j.logger.com.ibatis.common.util.StopWatch=DEBUG log4j.logger.java.sql.Connection=DEBUG log4j.logger.java.sql.Statement=DEBUG log4j.logger.java.sql.PreparedStatement=DEBUG log4j.logger.java.sql.ResultSet=DEBUG # Console output... log4j.appender.stdout=org.apache.log4j.ConsoleAppender log4j.appender.stdout.layout=org.apache.log4j.PatternLayout log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n