MyBatis3入门一（简单查询、插入）
1. 环境
mybatis-3.2版本，jdk1.6版本，Oracle数据库
2. 功能
实现基本的数据单条插入、单条查询功能。
3. 准备工作
3.1 下载mybatis-3.2，需要引用其中的若干包
mybatis-3.2.0.jar lib/asm-3.3.1.jar lib/cglib-2.2.2.jar lib/commons-logging-1.1.1.jar lib/javassist-3.17.1-GA.jar lib/log4j-1.2.17.jar lib/slf4j-api-1.7.2.jar lib/slf4j-log4j12-1.7.2.jar
3.2 项目的目录结构
src\com\clzhang\sample\struts2\mapper
MemberUserMapper.java mybatis的mapper处理类 src\com\clzhang\sample\struts2\mapper\entity
MemberUserBean.java mybatis的entity类 src\com\clzhang\sample\struts2\test
MyBatisTest.java 测试类，最终应该是在service的package中调用mapper中的方法。 resources\config
mybatis-config.xml mybatis的配置文件
resources\com\clzhang\sample\struts2\mapper
MemberUserMapper.xml mybatis的mapper配置文件
3.3 假定数据库已经创建，表结构也已经创建，并且有测试数据
这里数据库为Oracle，表名：MEMBER_USER，数据结构如下（假设已经存在测试数据）：
CREATE TABLE MEMBER_USER ( ID NUMBER NOT NULL PRIMARY KEY, NAME VARCHAR2(30), PERSONMOBILE VARCHAR2(20), ADDRESS VARCHAR2(255), AGE NUMBER);
4. 具体步骤
4.1 创建entity类
package com.clzhang.sample.struts2.mapper.entity; public class MemberUserBean { private int id; private String name; private String personMobile; private String address; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public String getPersonMobile() { return personMobile; } public void setPersonMobile(String personMobile) { this.personMobile = personMobile; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } }
4.2 创建mapper类
package com.clzhang.sample.struts2.mapper; import com.clzhang.sample.struts2.mapper.entity.MemberUserBean; public interface MemberUserMapper { public void insertUser(MemberUserBean user); public MemberUserBean getUser(int id); }
4.3 创建mybatis-config.xml的配置文件，位置于resources/config目录
<?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> <settings> <setting name="cacheEnabled" value="false" /> <setting name="useGeneratedKeys" value="true" /> <setting name="defaultExecutorType" value="REUSE" /> </settings> <typeAliases> <typeAlias alias="MemberUser" type="com.clzhang.sample.struts2.mapper.entity.MemberUserBean"/> </typeAliases> <environments default="development"> <environment id="development"> <transactionManager type="JDBC"/> <dataSource type="POOLED"> <property name="driver" value="oracle.jdbc.driver.OracleDriver"/> <property name="url" value="jdbc:oracle:thin:@192.168.2.136:1521:jingdu"/> <property name="username" value="jingdu"/> <property name="password" value="jingdu"/> </dataSource> </environment> </environments> <mappers> <mapper resource="com/clzhang/sample/struts2/mapper/MemberUserMapper.xml" /> </mappers> </configuration>
4.4 创建MemberUserMapper.xml配置文件，位置于：resources\com\clzhang\sample\struts2\mapper\
<?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.clzhang.sample.struts2.mapper.MemberUserMapper"> <cache /> <select id="getUser" resultType="MemberUser" parameterType="int"> select ID, NAME, PERSONMOBILE, PERSONREMARK, ADDRESS FROM MEMBER_USER WHERE ID = #{id} </select> <insert id="insertUser" parameterType="MemberUser"> INSERT INTO MEMBER_USER (ID, NAME, PERSONMOBILE, ADDRESS) VALUES(#{id}, #{name}, #{personMobile}, #{address}) </insert> </mapper>
4.5 创建测试类
package com.clzhang.sample.struts2.test; import java.io.IOException; import java.io.Reader; 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.clzhang.sample.struts2.mapper.MemberUserMapper; import com.clzhang.sample.struts2.mapper.entity.MemberUserBean; /** * mybatis的测试类，真正的应用，应该在service包中调用。 * @author Administrator * */ public class MyBatisTest { private static final String MYBATIS_CONFIG_FILENAME = "config/mybatis-config.xml"; private static SqlSessionFactory sqlSessionFactory; static { Reader reader = null; try { reader = Resources.getResourceAsReader(MYBATIS_CONFIG_FILENAME); } catch (IOException e) { System.out.println(e.getMessage()); } // 一旦你创建了 SqlSessionFactory 后,SqlSessionFactoryBuilder这个类就不需要存在了。 sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader); } /** * SqlSessionFactory 应该在你的应用执行期间都存在。没有理由来处理或重新创建它。 * @return */ public static SqlSessionFactory getSqlSessionFactory() { return sqlSessionFactory; } // @Test public void testAdd() { // SqlSession 的实例不能被共享,也是线程不安全的。因此最佳的范围是请求或方法范围。 SqlSession sqlSession = getSqlSessionFactory().openSession(); try { // 从技术上来说,当被请求时,任意映射器实例的最宽范围和 SqlSession 是相同的。最佳范围是方法范围。 MemberUserMapper mapper = sqlSession .getMapper(MemberUserMapper.class); MemberUserBean memberUser = new MemberUserBean(); memberUser.setId(1003); memberUser.setName("张三"); memberUser.setPersonMobile("18387887878"); memberUser.setAddress("北京丰台某公司"); mapper.insertUser(memberUser); sqlSession.commit(); } finally { sqlSession.close(); } } @Test public void getUser() { SqlSession sqlSession = getSqlSessionFactory().openSession(); try { MemberUserMapper mapper = sqlSession .getMapper(MemberUserMapper.class); MemberUserBean memberUser = mapper.getUser(725); System.out.println("name:" + memberUser.getName() + "\tmobile:" + memberUser.getPersonMobile() + "\taddress:" + memberUser.getAddress()); } finally { sqlSession.close(); } } }
测试输出：
name:吴经理 mobile:13695769533 address:浙江省乐清市北白象金炉工业区
