mybatis中的增删改查操作

在这一个部分，主要进行增删改查的示例书写。

增删改查可以基于xml的，也可以基于注解的方式。

一：对单条数据的查询

1.目录结构

　　这个使得目录更加清晰

　　

2.User.java

　　这个使用以前的user表。

　　因此，domain不需要改动。

3.配置文件

　　重要的参考部分是引用映射文件的部分

 <?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>
   <environments default="development">
     <environment id="development">
       <transactionManager type="JDBC">
         <property name="" value=""/>
       </transactionManager>
       <dataSource type="UNPOOLED">
         <property name="driver" value="com.mysql.jdbc.Driver"/>
         <property name="url" value="jdbc:mysql://127.0.0.1:3308/mybatis"/>
         <property name="username" value="root"/>
         <property name="password" value="123456"/>
       </dataSource>
     </environment>
   </environments>

    <mappers>
       <mapper resource="com/cao/sql/config/users.xml"/>
    </mappers>

 </configuration>

4.映射文件

 <?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">

 <mapper namespace="quickFirst">
     <resultMap type="com.cao.bean.User" id="User">
         <id column="ID" jdbcType="INTEGER" property="id"/>
         <result column="NAME" jdbcType="VARCHAR" property="name"/>
         <result column="AGE" jdbcType="INTEGER" property="age"/>
     </resultMap>
       <!-- 单条数据的查询，根据id查询 -->
     <select id="selectUserOne" parameterType="int" resultMap="User">
         SELECT * From users where id = #{id};
     </select>
 </mapper>

5.测试类

　　这个对于加载的配置文件的方式不同，稍微有点区别，顺便整理一下。

 package com.cao.test1;

 import java.io.IOException;
 import java.io.InputStream;
 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.cao.bean.User;
 /**
  * 这是一个对比程序
  * 当然也是一个根据条件，进行单条查询的程序
  * @author dell
  *
  */
 public class mainTest {
     /**
      * 查询单条数据
      * 根据id进行查询
      * @throws Exception
      */
     @Test
     public void testSelectOne1() throws Exception {
         String resources="/com/cao/config/Configuration.xml";       //这种方式在前面需要加一个/
         InputStream is=mainTest.class.getResourceAsStream(resources);
         SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(is);
         SqlSession sqlSession=sqlSessionFactory.openSession();
         String statement="quickFirst.selectUserOne";
         User user=sqlSession.selectOne(statement, 1);
         System.out.println(user);
     }
     @Test
     public void testSelectOne2() throws Exception {                    ////这种方式在前面不需要添加
         Reader reader=Resources.getResourceAsReader("com/cao/config/Configuration.xml");
         SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader);
         SqlSession sqlSession=sqlSessionFactory.openSession();
         String statement="quickFirst.selectUserOne";
         User user=sqlSession.selectOne(statement, 2);
         System.out.println(user);
     }
 }

二：插入数据

1.xml

 <!-- 插入数据 -->
     <insert id="insertData" parameterType="com.cao.bean.User">
         INSERT INTO USERS(name,age) value(#{name},#{age});
     </insert>

2.测试程序

 /**
      * 插入数据
      */
     @Test
     public void testInsert()throws Exception {
         Reader reader=Resources.getResourceAsReader("com/cao/config/Configuration.xml");
         SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader);
         SqlSession sqlSession=sqlSessionFactory.openSession();
         String statement="quickFirst.insertData";
         int insert=sqlSession.insert(statement, new User(-1,"KK",9));
         sqlSession.commit();
         System.out.println(insert);
         sqlSession.close();
     }

3.效果

　　打印出1，表示插入一条数据。

　　

　　数据库：

　　

三：删除数据

1.xml

 <!-- 删除数据 -->
     <delete id="deleteData" parameterType="int">
         DELETE FROM USERS where id=#{id};
     </delete>

2.测试程序

 /**
      * 删除数据
      */
     @Test
     public void testDelete()throws Exception {
         Reader reader=Resources.getResourceAsReader("com/cao/config/Configuration.xml");
         SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader);
         SqlSession sqlSession=sqlSessionFactory.openSession();
         String statement="quickFirst.deleteData";
         int delete=sqlSession.delete(statement, 4);
         System.out.println(delete);
         sqlSession.commit();
         sqlSession.close();
     }

3.效果

　　打印出1，表示删除一条数据。

　　

　　数据库：

　　

四：更新数据

1.xml

 <!-- 更新数据 -->
     <update id="updateData" parameterType="com.cao.bean.User">
         UPDATE USERS set name=#{name},age=#{age} where id=#{id};
     </update>

2.测试类

 /**
      * 更新数据
      */
     @Test
     public void testUpdate()throws Exception{
         Reader reader=Resources.getResourceAsReader("com/cao/config/Configuration.xml");
         SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader);
         SqlSession sqlSession=sqlSessionFactory.openSession();
         String statement="quickFirst.updateData";
         int update=sqlSession.update(statement, new User(3,"TT",99));
         sqlSession.commit();
         System.out.println(update);
         sqlSession.close();

     }

3.效果

　　打印1，表示更新一条数据。

　　

　　数据库：

　　

、

五：完整程序

1.xml

 <?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="quickFirst">
     <resultMap type="com.cao.bean.User" id="User">
         <id column="ID" jdbcType="INTEGER" property="id"/>
         <result column="NAME" jdbcType="VARCHAR" property="name"/>
         <result column="AGE" jdbcType="INTEGER" property="age"/>
     </resultMap>

       <!-- 单条数据的查询，根据id查询 -->
     <select id="selectUserOne" parameterType="int" resultMap="User">
         SELECT * From users where id = #{id};
     </select>

     <!-- 插入数据 -->
     <insert id="insertData" parameterType="com.cao.bean.User">
         INSERT INTO USERS(name,age) value(#{name},#{age});
     </insert>

     <!-- 删除数据 -->
     <delete id="deleteData" parameterType="int">
         DELETE FROM USERS where id=#{id};
     </delete>

     <!-- 更新数据 -->
     <update id="updateData" parameterType="com.cao.bean.User">
         UPDATE USERS set name=#{name},age=#{age} where id=#{id};
     </update>
 </mapper>

2.测试类

 package com.cao.test1;

 import java.io.IOException;
 import java.io.InputStream;
 import java.io.Reader;
 import java.sql.Connection;

 import org.apache.ibatis.io.Resources;
 import org.apache.ibatis.session.Configuration;
 import org.apache.ibatis.session.ExecutorType;
 import org.apache.ibatis.session.SqlSession;
 import org.apache.ibatis.session.SqlSessionFactory;
 import org.apache.ibatis.session.SqlSessionFactoryBuilder;
 import org.apache.ibatis.session.TransactionIsolationLevel;
 import org.junit.Test;

 import com.cao.bean.User;
 /**
  * 这是一个对比程序
  * 当然也是一个根据条件，进行单条查询的程序
  * @author dell
  *
  */
 public class mainTest {
     /**
      * 查询单条数据
      * 根据id进行查询
      * @throws Exception
      */
     @Test
     public void testSelectOne1() throws Exception {
         String resources="/com/cao/config/Configuration.xml";       //这种方式在前面需要加一个/
         InputStream is=mainTest.class.getResourceAsStream(resources);
         SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(is);
         SqlSession sqlSession=sqlSessionFactory.openSession();
         String statement="quickFirst.selectUserOne";
         User user=sqlSession.selectOne(statement, 1);
         System.out.println(user);
     }
     @Test
     public void testSelectOne2() throws Exception {                    ////这种方式在前面不需要添加
         Reader reader=Resources.getResourceAsReader("com/cao/config/Configuration.xml");
         SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader);
         SqlSession sqlSession=sqlSessionFactory.openSession();
         String statement="quickFirst.selectUserOne";
         User user=sqlSession.selectOne(statement, 2);
         System.out.println(user);
     }
     /**
      * 插入数据
      */
     @Test
     public void testInsert()throws Exception {
         Reader reader=Resources.getResourceAsReader("com/cao/config/Configuration.xml");
         SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader);
         SqlSession sqlSession=sqlSessionFactory.openSession();
         String statement="quickFirst.insertData";
         int insert=sqlSession.insert(statement, new User(-1,"KK",9));
         sqlSession.commit();
         System.out.println(insert);
         sqlSession.close();
     }
     /**
      * 删除数据
      */
     @Test
     public void testDelete()throws Exception {
         Reader reader=Resources.getResourceAsReader("com/cao/config/Configuration.xml");
         SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader);
         SqlSession sqlSession=sqlSessionFactory.openSession();
         String statement="quickFirst.deleteData";
         int delete=sqlSession.delete(statement, 4);
         System.out.println(delete);
         sqlSession.commit();
         sqlSession.close();
     }
     /**
      * 更新数据
      */
     @Test
     public void testUpdate()throws Exception{
         Reader reader=Resources.getResourceAsReader("com/cao/config/Configuration.xml");
         SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader);
         SqlSession sqlSession=sqlSessionFactory.openSession();
         String statement="quickFirst.updateData";
         int update=sqlSession.update(statement, new User(3,"TT",99));
         sqlSession.commit();
         System.out.println(update);
         sqlSession.close();

     }

 }

六：基于注解的增删改查

1.目录

　　

2.接口

 package com.cao.test1;

 import java.util.List;

 import org.apache.ibatis.annotations.Delete;
 import org.apache.ibatis.annotations.Insert;
 import org.apache.ibatis.annotations.Select;
 import org.apache.ibatis.annotations.Update;

 import com.cao.bean.User;

 public interface UserMapper {
     @Insert("INSERT INTO USERS(name,age) value(#{name},#{age})")
     public int add(User user);

     @Delete("DELETE FROM USERS where id=#{id}")
     public int delete(int id);

     @Update("UPDATE USERS set name=#{name},age=#{age} where id=#{id}")
     public int update(User user);

     @Select("SELECT * From users where id = #{id}")
     public User selectById(int id);

     @Select("SELECT * From users")
     public List<User> select();
 }

3.xml

　　重要的是需要将接口注册进去

 <?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>
   <environments default="development">
     <environment id="development">
       <transactionManager type="JDBC">
         <property name="" value=""/>
       </transactionManager>
       <dataSource type="UNPOOLED">
         <property name="driver" value="com.mysql.jdbc.Driver"/>
         <property name="url" value="jdbc:mysql://127.0.0.1:3308/mybatis"/>
         <property name="username" value="root"/>
         <property name="password" value="123456"/>
       </dataSource>
     </environment>
   </environments>

    <mappers>
       <mapper class="com.cao.test1.UserMapper"/>
    </mappers>

 </configuration>

4.测试类

 package com.cao.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.cao.bean.User;
 import com.cao.test1.UserMapper;

 public class MainTest {
     @Test
     public void test1() throws Exception {
         Reader reader=Resources.getResourceAsReader("com/cao/config/Configuration.xml");
         SqlSessionFactory sqlSessionFactory=new SqlSessionFactoryBuilder().build(reader);
         SqlSession sqlSession=sqlSessionFactory.openSession(true);                //true后是自动提交
         UserMapper userMapper=sqlSession.getMapper(UserMapper.class);
         int add=userMapper.add(new User(-1,"TT",89));
         System.out.println(add);
         sqlSession.close();
     }
 }

5.效果

　　

　　

、