0. pom.jar
<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis --> <dependency> <groupId>org.mybatis</groupId> <artifactId>mybatis</artifactId> <version>3.5.3</version> </dependency>
1. mapper.xml
1 <?xml version="1.0" encoding="UTF-8"?> 2 <!DOCTYPE mapper 3 PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" 4 "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> 5 <mapper namespace="com.xing.mapper.AccountMapper"> 6 <delete id="deleteAll"> 7 delete from `account`; 8 </delete> 9 </mapper>
2. SqlMapConfig.xml
1 <?xml version="1.0" encoding="UTF-8"?> 2 <!DOCTYPE configuration 3 PUBLIC "-//mybatis.org//DTD Config 3.0//EN" 4 "http://mybatis.org/dtd/mybatis-3-config.dtd"> 5 <configuration> 6 <environments default="development"> 7 <environment id="development"> 8 <transactionManager type="JDBC" /> 9 <dataSource type="POOLED"> 10 <property name="driver" value="com.mysql.jdbc.Driver" /> 11 <property name="url" value="jdbc:mysql:///student" /> 12 <property name="username" value="root" /> 13 <property name="password" value="123" /> 14 </dataSource> 15 </environment> 16 </environments> 17 <mappers> 18 <!-- 加载sql语句的配置文件 --> 19 <mapper resource="mapper.xml"/> 20 </mappers> 21 </configuration>
3. Interface AccountMapper
1 package com.xing.mapper; 2 import com.xing.beans.Account; 3 import java.util.List; 4 public interface AccountMapper { 5 void deleteAll(); 6 List<Account> findAll(); 7 void deleteById( Integer id); 8 Account findById(Integer id); 9 double findMoneyById(Integer id); 10 }
4. Class Test
1 package com.xing.test2; 2 3 import com.xing.beans.Account; 4 import com.xing.mapper.AccountMapper; 5 import org.apache.ibatis.io.Resources; 6 import org.apache.ibatis.session.SqlSession; 7 import org.apache.ibatis.session.SqlSessionFactory; 8 import org.apache.ibatis.session.SqlSessionFactoryBuilder; 9 import org.junit.Test; 10 11 import java.io.IOException; 12 import java.util.List; 13 14 public class Test1 { 15 @Test 16 public void te1() throws IOException { 17 SqlSession sqlSession = new SqlSessionFactoryBuilder().build(Resources.getResourceAsStream("SqlMapConfig.xml")).openSession(); 18 AccountMapper mapper = sqlSession.getMapper(AccountMapper.class); 19 mapper.deleteById(2); 20 sqlSession.commit(); 21 } 22 23 @Test 24 public void test2() throws IOException { 25 SqlSession sqlSession = new SqlSessionFactoryBuilder().build(Resources.getResourceAsStream("SqlMapConfig.xml")).openSession(); 26 AccountMapper mapper = sqlSession.getMapper(AccountMapper.class); 27 List<Account> all = mapper.findAll(); 28 29 }
注意：
1. 在做查询操作时，配置 mapper.xml 里 返回值类型 写为 对象不用写集合，当查询返回是对象集合时，会自动的转换的