MyBatis-03-Mapper.rar

package com.qiaobc.mybatis.tests; 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; import org.junit.Test; import com.qiaobc.mybatis.beans.Employee; import com.qiaobc.mybatis.dao.EmployeeMapper; public class MybatisTest { /** * 增删改测试 * 1. MyBatis允许增删改直接定义以下类型的返回值：Integer、Long、Boolean、void * 2. sqlSessionFactory.openSession(); //需要手动提交数据 * sqlSessionFactory.openSession(); //主动提交 * @throws Exception */ @Test public void test3() throws Exception { // 1. 创建SqlSessionFactory实例：根据MyBatis全局配置文件 String resource = "mybatis-config.xml"; InputStream inputStream = Resources.getResourceAsStream(resource); SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream); // 2. 获取SqlSession实例：其能够执行已经映射的SQL语句；且一个SqlSession对象代表和数据库的一次会话； // 需要手动提交数据 SqlSession sqlSession = sqlSessionFactory.openSession(); try { EmployeeMapper mapper = sqlSession.getMapper(EmployeeMapper.class); Employee employee = new Employee(null, "baobei", "1", "baobei@163.com"); System.out.println(mapper.addEmployee(employee)); System.out.println("id = " + employee.getId()); // Employee employee = new Employee(2, "baobei2", "1", "baobei2@163.com"); // mapper.updateEmployee(employee); // mapper.deleteEmployee(4); sqlSession.commit(); } finally { // 5. 关闭SqlSession实例 sqlSession.close(); } } /** * 面向接口编程 * @throws Exception */ @Test public void test2() throws Exception { // 1. 创建SqlSessionFactory实例：根据MyBatis全局配置文件 String resource = "mybatis-config.xml"; InputStream inputStream = Resources.getResourceAsStream(resource); SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream); // 2. 获取SqlSession实例：其能够执行已经映射的SQL语句；且一个SqlSession对象代表和数据库的一次会话； SqlSession sqlSession = sqlSessionFactory.openSession(); try { // 3. 创建接口的实现类对象 EmployeeMapper mapper = sqlSession.getMapper(EmployeeMapper.class); System.out.println(mapper); //org.apache.ibatis.binding.MapperProxy@4efce9a2 // 将接口与SQL映射文件动态绑定后，MyBatis会为该接口自动地创建一个代理对象，代理对象来执行数据库操作 // 4. 调用接口的查询方法 Employee employee = mapper.getEmployeeById(3); System.out.println(employee); } finally { // 5. 关闭SqlSession实例 sqlSession.close(); } } @Test public void test1() throws Exception { // 1. 创建SqlSessionFactory实例：根据MyBatis全局配置文件 String resource = "mybatis-config.xml"; InputStream inputStream = Resources.getResourceAsStream(resource); SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream); // 2. 获取SqlSession实例：其能够执行已经映射的SQL语句；且一个SqlSession对象代表和数据库的一次会话； SqlSession sqlSession = sqlSessionFactory.openSession(); // 3. 执行已经映射的Sql语句 // SQL语句的唯一标识：statement Unique identifier matching the statement to use. // 执行SQL语句所需要的参数：A parameter object to pass to the statement. try { Employee employee = sqlSession.selectOne("selectEmployee", 2); System.out.println(employee); } finally { // 4. 关闭SqlSession实例 sqlSession.close(); } } }