详解java基于MyBatis使用示例

<dependency>
  <groupId>org.mybatis</groupId>
  <artifactId>mybatis</artifactId>
  <version>3.2.3</version>
</dependency>
<dependency>
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-java</artifactId>
  <version>5.1.26</version>
</dependency>

CREATE DATABASE mybatis_test;

CREATE TABLE user
(
  age INTEGER NOT NULL,
  name VARCHAR(64) NOT NULL DEFAULT ''

);

insert user values(18,'zhanjindong');
insert user values(20,'zhangsan');

<?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>  
    <!-- changes from the defaults for testing -->  
    <setting name="cacheEnabled" value="false" />  
    <setting name="useGeneratedKeys" value="true" />  
    <setting name="defaultExecutorType" value="REUSE" />  
  </settings>  
  <typeAliases>  
    <typeAlias alias="User" type="test.mybatis.User"/>  
  </typeAliases>  
  <environments default="development">  
    <environment id="development">  
      <transactionManager type="jdbc"/>  
      <dataSource type="POOLED">  
       <property name="driver" value="com.mysql.jdbc.Driver"/>  
       <property name="url" value="jdbc:mysql://192.168.71.38:3306/mybatis_test"/>  
       <property name="username" value="root"/>  
       <property name="password" value="123456"/>  
      </dataSource>  
    </environment>  
  </environments>  
  <mappers>  
    <mapper resource="mappers/UserMapper.xml" />  
  </mappers>  
</configuration>

<?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="test.mybatis.UserMapper">
  <!-- 这里namespace必须是UserMapper接口的路径” -->
  <insert id="insertUser" parameterType="User">
    insert into user(name,age) values(#{name},#{age})
    <!-- 这里sql结尾不能加分号，否则报“ORA-00911”的错误 -->
  </insert>

  <!-- 这里的id必须和UserMapper接口中的接口方法名相同 -->
  <select id="getUser" resultType="User" parameterType="java.lang.String">
    select * from user where name=#{name}
  </select>
</mapper>

package test.mybatis;

public interface UserMapper {
  public void insertUser(User user);

  public User getUser(String name);
}

package test.mybatis;

public class User {
  private String name;
  private Integer age;

  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }

  public Integer getAge() {
    return age;
  }

  public void setAge(Integer age) {
    this.age = age;
  }

  public User(String name, Integer age) {
    super();
    this.name = name;
    this.age = age;
  }

  public User() {
    super();
  }
}

package test.mybatis;

import java.io.IOException;
import java.io.Reader;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

public class MyBatisUtil {
  private final static SqlSessionFactory sqlSessionFactory;
  static {
    String resource = "mybatis-config.xml";
    Reader reader = null;
    try {
      reader = Resources.getResourceAsReader(resource);
    } catch (IOException e) {
      System.out.println(e.getMessage());

    }
    sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
  }

  public static SqlSessionFactory getSqlSessionFactory() {
    return sqlSessionFactory;
  }
}

package test.mybatis;

import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;

public class TestMyBatis {
  static SqlSessionFactory sqlSessionFactory = null;
  static {
    sqlSessionFactory = MyBatisUtil.getSqlSessionFactory();
  }

  public static void main(String[] args) {
    testAdd();
    getUser();
  }

  public static void testAdd() {
    SqlSession sqlSession = sqlSessionFactory.openSession();
    try {
      UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
      User user = new User("lisi", new Integer(25));
      userMapper.insertUser(user);
      sqlSession.commit();// 这里一定要提交，不然数据进不去数据库中
    } finally {
      sqlSession.close();
    }
  }

  public static void getUser() {
    SqlSession sqlSession = sqlSessionFactory.openSession();
    try {
      UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
      User user = userMapper.getUser("zhangsan");
      System.out.println("name: " + user.getName() + "|age: "
          + user.getAge());
    } finally {
      sqlSession.close();
    }
  }
}