MyBatis-事务管理

项目截图

项目建立步骤：
1、在src目录下建立dp.properties文件，存放配置信息（需要自己在Oracle数据库建表）

jjdbc.driver=oracle.jdbc.OracleDriver
jdbc.url=jdbc:oracle:thin:@localhost:1521:orcl
jdbc.username=bjsxt
jdbc.password=123

2、建立MyBatisUtil工具类

package cn.bjsxt.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 MyBatisUtil {
	private static SqlSessionFactory factory=null;
	
	static {
		
		try {
			InputStream is = Resources.getResourceAsStream("mybatis-cfg.xml");
			factory=new SqlSessionFactoryBuilder().build(is);
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
	public static SqlSession getSession() {
		SqlSession session=null;
		if (factory!=null) {
			//true表示开启自动提交功能,防止回滚，但是运行多条sql语句可能出问题
			//session=factory.openSession(true);
			session=factory.openSession();
		}
		return session;
	}
}

3、log4j.properties 文件,设置日志输出格式

# Set root category priority to INFO and its only appender to CONSOLE.
log4j.rootCategory=ERROR, CONSOLE
# log4j.rootCategory=DEBUG, CONSOLE, LOGFILE

# 单独设置sql语句的输出级别为DEBUG级别
#方法级别
#log4j.logger.cn.bjsxt.mapper.UserMapper.selAll=DEBUG
#类级别
# log4j.logger.cn.bjsxt.mapper.UserMapper=DEBUG
# 包级别
log4j.logger.cn.bjsxt.mapper=DEBUG

# CONSOLE is set to be a ConsoleAppender using a PatternLayout.
log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender
log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout
log4j.appender.CONSOLE.layout.ConversionPattern=- %m%n

# LOGFILE is set to be a File appender using a PatternLayout.
log4j.appender.LOGFILE=org.apache.log4j.FileAppender
log4j.appender.LOGFILE.File=d:/test.log
log4j.appender.LOGFILE.Append=true
log4j.appender.LOGFILE.layout=org.apache.log4j.PatternLayout
log4j.appender.LOGFILE.layout.ConversionPattern=- %m %l%n

4、mybatie-cfg.xml 框架主要的配置文件

<?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 加载外部文件 -->
	<properties resource="db.properties"></properties>
	<!-- 用于指定使用哪个环境 mysql故障 故采用oracle default:用于指定使用的环境id -->
	<settings>
		<!-- 设置mybatis使用log4j支持 -->
		<setting name="logImpl" value="LOG4J" />
	</settings>
	<typeAliases>
		<!-- typeAlias 给类起别名,在UserMapper使用时直接引用类名即可 -->
		<!-- <typeAlias type="cn.bjsxt.pojo.User"/> -->
		<package name="cn.bjsxt.pojo" />
	</typeAliases>
	<environments default="dev">
		<!-- 用于配置开发环境 id：环境的唯一识别码 -->
		<environment id="dev">
			<!-- 事务管理器 type：用于设置mybaties采用什么方式管理事务 JDBC表示采用和JDBC一样的事务管理方式 -->
			<transactionManager type="JDBC"></transactionManager>
			<!-- 数据源/连接池，用于配置连接池和数据库连接的参数 type：用于设置mybatis是否采用连接池技术 POOLED表示mybatis采用连接池技术 -->
			<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>
	<!-- 扫描mapper文件 -->
	<mappers>
		<mapper resource="cn/bjsxt/mapper/UserMapper.xml" />
	</mappers>
</configuration>

5、UserMapper.xml配置文件

<?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,可以随意定义，一般情况下要写全限定路径
  	MyBatis管理SQL语句是通过namespace+id来定位的
   -->
<mapper namespace="cn.bjsxt.mapper.UserMapper">
	<!-- 新增 -->
	<insert id="insUser" parameterType="user">
		insert into t_user values(#{id},#{username},#{password})
	</insert>
	<!--  修改 -->
	<update id="updUser" parameterType="user">
		update t_user set username=#{username},password=#{password} where id=#{id}
	</update>
	<update id="delUser" parameterType="user">
		delete from t_user where id=#{id}
	</update>
</mapper>

6、实体类

package cn.bjsxt.pojo;

import java.io.Serializable;

public class User implements Serializable {
	private int id;
	private String username;
	private String password;

	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 getPassword() {
		return password;
	}

	public void setPassword(String password) {
		this.password = password;
	}

	public User(int id, String username, String password) {
		super();
		this.id = id;
		this.username = username;
		this.password = password;
	}

	public User() {
		super();
	}

	@Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + id;
		result = prime * result + ((password == null) ? 0 : password.hashCode());
		result = prime * result + ((username == null) ? 0 : username.hashCode());
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		User other = (User) obj;
		if (id != other.id)
			return false;
		if (password == null) {
			if (other.password != null)
				return false;
		} else if (!password.equals(other.password))
			return false;
		if (username == null) {
			if (other.username != null)
				return false;
		} else if (!username.equals(other.username))
			return false;
		return true;
	}

	@Override
	public String toString() {
		return "User [id=" + id + ", username=" + username + ", password=" + password + "]";
	}

}

7、主类

package cn.bjsxt.test;

import org.apache.ibatis.session.SqlSession;
import org.junit.Test;

import cn.bjsxt.pojo.User;
import cn.bjsxt.util.MyBatisUtil;

public class TestInsert {
	@Test
	public void TestDel() {
		SqlSession session = MyBatisUtil.getSession();
		User user = new User();
		user.setId(8);
		
		int num = session.delete("cn.bjsxt.mapper.UserMapper.delUser", user);
		if (num>0) {
			System.out.println("删除成功");
			session.commit();
		} else {
			System.out.println("删除失败");
			session.rollback();
		}
	}
	
	@Test
	public void testUpd() {
		SqlSession session = MyBatisUtil.getSession();
		User user = new User();
		user.setId(8);
		user.setUsername("普京");
		user.setPassword("666");
		
		int num = session.update("cn.bjsxt.mapper.UserMapper.updUser", user);
		if (num>0) {
			System.out.println("更新成功");
			session.commit();
		}else {
			System.out.println("更新失败");
			session.rollback();
		}
		session.close();
	}
	//使用junit时，每次要运行一个方法都要在方法前面加@Test，否则会报无法解析的异常
	
	@Test
	public void testIns() {
		SqlSession session = MyBatisUtil.getSession();
		User user = new User();
		user.setId(8);
		user.setUsername("小京");
		user.setPassword("123");
		
		int num = session.insert("cn.bjsxt.mapper.UserMapper.insUser", user);
		if (num>0) {
			//成功时，提交事务，防止回滚
			System.out.println("新增成功");
			session.commit();
		}else {
			//失败时，回滚事务
			System.out.println("新增失败");
			session.rollback();
		}
		//关闭资源
		session.close();
	}
	
	
}

8、运行结果演示（因为该数据已经插入，所以插入失败）