普通模式

自定義接口，接口實現類。

思考：需要sqlSessionFactory，生產sqlSession。

UserDao:

package dao;

import java.util.List;
import domain.User;

public interface UserDao {
	//根據Id查詢用戶
	public User findUserByID(Integer id);
	//根據用戶名進行模糊查詢
	public List<User> findUserByUsername(String username);

}

UserDaoImpl:

package dao.impl;

import java.util.List;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import dao.UserDao;
import domain.User;

public class UserDaoImpl implements UserDao{
	
	//namespace
	private String ns="test.";

	private SqlSessionFactory sqlSessionFactory;
	public UserDaoImpl(SqlSessionFactory sqlSessionFactory){
		this.sqlSessionFactory=sqlSessionFactory;
	}
	
	public User findUserByID(Integer id) {
		SqlSession sqlSession=sqlSessionFactory.openSession();
		User user = sqlSession.selectOne(ns+"findUserByID",id);
		
		return user;
	}

	public List<User> findUserByUsername(String username) {
		SqlSession sqlSession=sqlSessionFactory.openSession();
		List<User> list=sqlSession.selectList(ns+"findUserByUsername", username);
		
		return list;
	}
}

Main3:

package test;

import static org.hamcrest.CoreMatchers.nullValue;
import java.io.IOException;
import java.io.InputStream;
import java.util.Date;
import java.util.List;
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.Before;
import org.junit.Test;
import dao.UserDao;
import dao.impl.UserDaoImpl;
import domain.User;

public class Main3 {

	SqlSessionFactory sqlSessionFactory=null;
	
	@Before
	public void beforeConf() throws IOException{
		String resources="sqlMapConfig.xml";
		InputStream inputStream=Resources.getResourceAsStream(resources);
		sqlSessionFactory=new SqlSessionFactoryBuilder().build(inputStream);
		
	}
	
	//普通dao開發模式
	@Test
	public void commonDao(){
		UserDao userDao=new UserDaoImpl(sqlSessionFactory);
		//根據Id查詢用戶
		User user1 = userDao.findUserByID(16);
		System.out.println("user1:::"+user1);
		
		//根據名字模糊查詢用戶
		List<User> list = userDao.findUserByUsername("張");
		System.out.println(list);
	}
}

接口代理開發模式

自需要定義接口。

開發約定：

l 映射文件namespace必須是接口全類路徑名。

l 映射文件的Statement的id必須和接口的方法名一致。

sqlMapConfig.xml:

<?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">
<!-- 配置文件開始，所有配置文件都必須在configuration -->
<configuration>
	<!-- 可以配置多個運行環境，但是每個 SqlSessionFactory 實例只能選擇一個運行環境   
	  一、development:開發模式
	   二、work：工作模式-->
	<environments default="development">
		 <!--id屬性必須和上面的default一樣  -->
		<environment id="development">
			<!-- mybatis事務管理器 ,由jdbc管理-->
			<transactionManager type="JDBC"/>
			<!--  mybatis連接池 -->
			<dataSource type="POOLED">
				<property name="driver" value="com.mysql.jdbc.Driver"/>
				<property name="url" value="jdbc:mysql:///mybatis01"/>
				<property name="username" value="root"/>
				<property name="password" value="moujinling321"/>
			</dataSource>
		</environment>
	</environments>
	<!-- 引入外部映射文件 -->
	<mappers>
		<mapper resource="sqlMap/User.xml"/>
	</mappers>
</configuration>

User.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">
<!-- 
	MyBatis映射文件的開始標簽 ,所有sql語句全部封裝在mapper裏面
	namespace:命名空間
		*隔離不同的映射文件，映射文件的唯一標識，可以任意命名
		*在接口代理開發中，namespace具有特殊含義，不能任意命名
			namespace需要寫接口的全路徑
	-->
<mapper namespace="dao.UserMapper">
	<!-- statement的id必須和接口中的方法名相同 -->
	<select id="findUserByID" parameterType="int" resultType="domain.User">
		select * from user where id=#{id}
	</select>
	
	
	<select id="findUserByUsername" resultType="domain.User" parameterType="string">
		select * from user where username like ‘%${value}%‘
	</select>
	
</mapper>

UserMapper:

package dao;

import java.util.List;
import domain.User;

public interface UserMapper {
	//根據Id查詢用戶
	public User findUserByID(Integer id);
	//根據用戶名進行模糊查詢
	public List<User> findUserByUsername(String username);

}

Main1:

package test;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;
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.Before;
import org.junit.Test;
import dao.UserMapper;
import domain.User;

public class Main1 {
	SqlSessionFactory sqlSessionFactory=null;
	
	@Before
	public void beforeConf() throws IOException{		
		String resources = "sqlMapConfig.xml";
		InputStream inputStream = Resources.getResourceAsStream(resources);
		sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
	}

	//接口代理開發模式
	@Test
	public void proxyInterface(){
		SqlSession sqlSession=sqlSessionFactory.openSession();
		
		//獲取代理對象
		UserMapper userMapper = sqlSession.getMapper(UserMapper.class);
		//根據Id查詢
		User user = userMapper.findUserByID(24);
		System.out.println(user);
		
		//根據用戶名進行模糊查詢
		List<User> users=userMapper.findUserByUsername("張");
		System.out.println(users);
	}
}

2.Mybatis兩種開發模式