mybatis基础学习二

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操作users表的CRUD

XML实现方式

  • 定义sql映射xml文件 userMapper.xml
  1. <?xml version="1.0" encoding="UTF-8" ?>
  2. <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> 
  3. <mapper namespace="mybatis.userMapper"> 
  4.     <!-- <select id="getid" parameterType="int" 
  5.         resultType="mybatis.User">
  6.         select * from users where id=#{id}
  7.     </select> -->
  9.     <insert id="insertUser" parameterType="mybatis.User">
  10.     insert into users(name, age) values(#{name}, #{age});
  11.     </insert>
  13.     <delete id="deleteUser" parameterType="int">
  14.     delete from users where id=#{id}
  15.     </delete>
  17.     <update id="updateUser" parameterType="mybatis.User">
  18.     update users set name=#{name},age=#{age} where id=#{id}
  19.     </update>
  21.     <select id="selectUser" parameterType="int" resultType="mybatis.User">
  22.     select * from users where id=#{id}
  23.     </select>
  25.     <select id="selectAllUsers" resultType="mybatis.User">
  26.     select * from users
  27.     </select>    
  28. </mapper>
  • 在conf.xml中注册该映射文件
  1. <?xml version="1.0" encoding="UTF-8"?>
  2. <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
  3. <configuration>
  4.     <environments default="development">
  5.         <environment id="development">
  6.             <transactionManager type="JDBC" />
  7.             <dataSource type="POOLED">
  8.                 <property name="driver" value="com.mysql.jdbc.Driver" />
  9.                 <property name="url" value="jdbc:mysql://172.171.2.161:3306/mybatis" />
  10.                 <property name="username" value="root" />
  11.                 <property name="password" value="root123" />
  12.             </dataSource>
  13.         </environment>
  14.     </environments>
  16.     <mappers>
  17.     <!--xml方式  -->
  18.         <mapper resource="mybatis/userMapper.xml"/>
  20.     </mappers>
  23. </configuration>
  • 封装得到session的方法，MybatisUtil.java
  1. package mybatis;
  3. import java.io.InputStream;
  5. import org.apache.ibatis.session.SqlSession;
  6. import org.apache.ibatis.session.SqlSessionFactory;
  7. import org.apache.ibatis.session.SqlSessionFactoryBuilder;
  10. public class MybatisUtil
  11. {
  12.     //返回session
  13.     public static SqlSession openSqlSession()
  14.     {
  15.         String resource = "conf.xml";
  17.         InputStream is = Test.class.getClassLoader().getResourceAsStream(resource);
  19.         SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);
  21.         SqlSession session = factory.openSession();
  22.         //貌似可有可无
  23.         session.commit();
  24.         return session;
  25.     }
  27. }
  • 编写测试类 Test.java

插入用户

  1. package mybatis;
  3. import java.io.IOException;
  5. public class Test
  6. {
  8.     public static void main(final String[] args) throws IOException
  9.     {
  10.         /**
  11.          * xml方式测试
  12.          */
  14.         String statement = "mybatis.userMapper.insertUser";
  16.         int tuser = MybatisUtil.openSqlSession().insert(statement, new User(3, "rose", 3));
  17.         MybatisUtil.openSqlSession().close();
  18.         System.out.println(tuser);
  19.     }
  21. }

更新用户

  1. package mybatis;
  3. import java.io.IOException;
  5. public class Test
  6. {
  8.     public static void main(final String[] args) throws IOException
  9.     {
  10.         /**
  11.          * xml方式测试
  12.          */
  14.         String statement = "mybatis.userMapper.updateUser";
  16.         int tuser = MybatisUtil.openSqlSession().update(statement, new User(3, "rose", 3));
  17.         MybatisUtil.openSqlSession().close();
  18.         System.out.println(tuser);
  19.     }
  21. }

删除用户

  1. package mybatis;
  3. import java.io.IOException;
  5. public class Test
  6. {
  8.     public static void main(final String[] args) throws IOException
  9.     {
  10.         /**
  11.          * xml方式测试
  12.          */
  14.         String statement = "mybatis.userMapper.deleteUser";
  16.         int tuser = MybatisUtil.openSqlSession().delete(statement,2));
  17.         MybatisUtil.openSqlSession().close();
  18.         System.out.println(tuser);
  19.     }
  21. }

查询全部用户

  1. package mybatis;
  3. import java.io.IOException;
  5. public class Test
  6. {
  8.     public static void main(final String[] args) throws IOException
  9.     {
  10.         /**
  11.          * xml方式测试
  12.          */
  14.         String statement = "mybatis.userMapper.selectAllUsers";
  16.         List<User> tuser = MybatisUtil.openSqlSession().selectList(statement);
  17.         MybatisUtil.openSqlSession().close();
  18.         System.out.println(tuser);
  19.     }
  21. }

注解实现方式

  • 定义sql接口文件 UserMapperDe.java
  1. package mybatis;
  3. import java.util.List;
  5. import org.apache.ibatis.annotations.Delete;
  6. import org.apache.ibatis.annotations.Insert;
  7. import org.apache.ibatis.annotations.Select;
  8. import org.apache.ibatis.annotations.Update;
  10. public interface UserMapperDe
  11. {
  13.     @Insert("insert into users(name, age) values(#{name}, #{age})")
  14.     public int insertUser(User user);
  16.     @Delete("delete from users where id=#{id}")
  17.     public int deleteUserById(int id);
  19.     @Update("update users set name=#{name},age=#{age} where id=#{id}")
  20.     public int updateUser(User user);
  22.     @Select("select * from users where id=#{id}")
  23.     public User getUserById(int id);
  25.     @Select("select * from users")
  26.     public List<User> getAllUser();
  28. }
  • 在conf.xml中注册该接口文件
  1. <?xml version="1.0" encoding="UTF-8"?>
  2. <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd">
  3. <configuration>
  4.     <environments default="development">
  5.         <environment id="development">
  6.             <transactionManager type="JDBC" />
  7.             <dataSource type="POOLED">
  8.                 <property name="driver" value="com.mysql.jdbc.Driver" />
  9.                 <property name="url" value="jdbc:mysql://172.171.2.161:3306/mybatis" />
  10.                 <property name="username" value="root" />
  11.                 <property name="password" value="root123" />
  12.             </dataSource>
  13.         </environment>
  14.     </environments>
  16.     <mappers>
  17.     <!--xml方式  -->
  18.         <mapper resource="mybatis/userMapper.xml"/>
  19.         <!--注解方式  -->
  20.         <mapper class="mybatis.UserMapperDe"/>
  21.     </mappers>
  24. </configuration>
  • 编写测试类 TestClass.java

插入用户

  1. package mybatis;
  3. import java.io.IOException;
  5. public class Test
  6. {
  8.     public static void main(final String[] args) throws IOException
  9.     {
  11.         /**
  12.          * 注解方式测试
  13.          */
  14.         UserMapperDe mapper = MybatisUtil.openSqlSession().getMapper(UserMapperDe.class);
  15.         int inuser = mapper.insertUser(new User(-1, "clock", 1));
  16.         MybatisUtil.openSqlSession().close();
  17.         System.out.println(inuser);
  18.     }
  20. }

更新用户

  1. package mybatis;
  3. import java.io.IOException;
  5. public class Test
  6. {
  8.     public static void main(final String[] args) throws IOException
  9.     {
  11.         /**
  12.          * 注解方式测试
  13.          */
  14.         UserMapperDe mapper = MybatisUtil.openSqlSession().getMapper(UserMapperDe.class);
  15.         int inuser = mapper.updateUser(new User(2, "efpd", 2));
  16.         MybatisUtil.openSqlSession().close();
  17.         System.out.println(inuser);
  18.     }
  20. }

删除用户

  1. package mybatis;
  3. import java.io.IOException;
  5. public class Test
  6. {
  8.     public static void main(final String[] args) throws IOException
  9.     {
  11.         /**
  12.          * 注解方式测试
  13.          */
  14.         UserMapperDe mapper = MybatisUtil.openSqlSession().getMapper(UserMapperDe.class);
  15.         int inuser = mapper.deleteUserById(2);
  16.         MybatisUtil.openSqlSession().close();
  17.         System.out.println(inuser);
  18.     }
  20. }

查询全部用户

  1. package mybatis;
  3. import java.io.IOException;
  5. public class Test
  6. {
  8.     public static void main(final String[] args) throws IOException
  9.     {
  11.         /**
  12.          * 注解方式测试
  13.          */
  14.         UserMapperDe mapper = MybatisUtil.openSqlSession().getMapper(UserMapperDe.class);
  15.         List<User> inuser = mapper.getAllUser();
  16.         MybatisUtil.openSqlSession().close();
  17.         System.out.println(inuser);
  18.     }
  20. }




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