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mybatis配置SQL语句的方式

程序员文章站 2022-05-23 13:24:07
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配置MAPPER的方式有四种,不过现在只用了两种。
一种是通过XML方式配置,另一种是通过接口+注解
先看第一种:

<?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="com.lonton.mybatis.filemapper">
	
	<select id="findPage" parameterType="map" resultType="fileinfo">
		select * from file_info  limit #{begin},#{size} 
	</select>
	<select id="findPageOrder" parameterType="map" resultType="fileinfo">
		select * from file_info  order by #{column} #{order} limit #{begin},#{size} 
	</select>
	
	<select id="findAll" resultType="fileinfo">
		select * from file_info 
	</select>
	
	<select id="search" parameterType="String" resultType="fileinfo">
		select * from file_info  where name like #{name}
	</select>
	
	<select id="selectCount" resultType="int">
		select count(*)  from file_info 
	</select>

</mapper>


通过接口+注解:
package com.lonton.testMyBatis.dao;

import java.util.List;

import org.apache.ibatis.annotations.Param;
import org.apache.ibatis.annotations.Select;


import com.lonton.testMyBatis.pojo.Fileinfo;

public interface FileinfoDao {

	@Select("select * from file_info")
	public List<Fileinfo> findAll();
	
	@Select("select * from file_info limit #{begin},#{size}")
	public List<Fileinfo> findPage(@Param("map")int page,int pageSize);//注解参数的意思是传给MyBatis API的参数
	
	
	public List<Fileinfo> findPageOrder(int page,int pageSize,String column,String order);
	
	@Select("select count(*) from file_info")
	public int getCount();
	
	@Select("select * from file_info where name like #{name}")
	public List<Fileinfo> search(@Param("name") String name);
	
}



最后的实现类是这样的:

package com.lonton.testMyBatis.daoImpl;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.lonton.testMyBatis.dao.BaseDao;
import com.lonton.testMyBatis.dao.FileinfoDao;
import com.lonton.testMyBatis.pojo.Fileinfo;

public class FileinfoDaoImpl extends BaseDao implements FileinfoDao{

	@Override
	public List<Fileinfo> findAll() {
		return sessionFactory.openSession().selectList("com.lonton.mybatis.filemapper.findAll");
	}

	@Override
	public List<Fileinfo> findPage(int page, int pageSize) {
		Map<String,Integer> map = new HashMap<String,Integer>();
		map.put("begin", (page-1)*pageSize);
		map.put("size", pageSize);
		//XML
		//return sessionFactory.openSession().selectList("com.lonton.mybatis.filemapper.findPage", map);
		//interface
		return sessionFactory.openSession().selectList("com.lonton.testMyBatis.dao.FileinfoDao.findPage",map);
	}

	@Override
	public int getCount() {
		/*
		 *  XML MAPPER 
		 *  路径是 namespace+id
		 */
		//return sessionFactory.openSession().selectOne("com.lonton.mybatis.filemapper.selectCount");
		
		/*
		 * interface MAPPER
		 * 路径应该是:包名+类名+方法
		 */
		return sessionFactory.openSession().selectOne("com.lonton.testMyBatis.dao.FileinfoDao.getCount");
	}

	@Override
	public List<Fileinfo> search(String name) {
		return sessionFactory.openSession().selectList("com.lonton.mybatis.filemapper.search", "%"+name+"%");
	}

	@Override
	public List<Fileinfo> findPageOrder(int page, int pageSize, String column,
			String order) {
		Map<String,Object> map = new HashMap<String,Object>();
		map.put("begin", (page-1)*pageSize);
		map.put("size", pageSize);
		map.put("column", column);
		map.put("order", order);
		return sessionFactory.openSession().selectList("com.lonton.mybatis.filemapper.findPageOrder", map);
	
	}

}

相关标签: mybatis 配置