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mybatis(3)分页查询和条件分页查询

mybatis.xml,db.properties, MybatisUtil.java ,student.java和第一篇文章一样,所建的表也是一样的

StudentDao.java

/**
 * 持久层 
 * @author AdminTC
 */
public class StudentDao {
	/**
	 * 增加学生
	 */
	public void add(Student student) throws Exception{
		SqlSession sqlSession = null;
		try{
			sqlSession = MybatisUtil.getSqlSession();
			sqlSession.insert(Student.class.getName()+".add",student);
			sqlSession.commit();
		}catch(Exception e){
			e.printStackTrace();
			sqlSession.rollback();
			throw e;
		}finally{
			MybatisUtil.closeSqlSession();
		}
	}
	/**
	 * 无条件分页
	 * @param start 表示在mysql中从第几条记录的索引号开始显示,索引从0开始
	 * @param size 表示在mysql中最多显示几条记录
	 */
	public List<Student> findAllWithFy(int start,int size) throws Exception{
		SqlSession sqlSession = null;
		try{
			sqlSession = MybatisUtil.getSqlSession();
			
			Map<String,Object> map = new LinkedHashMap<String,Object>();
			map.put("pstart",start);
			map.put("psize",size);
			return sqlSession.selectList(Student.class.getName()+".findAllWithFy",map);
		}catch(Exception e){
			e.printStackTrace();
			throw e;
		}finally{
			MybatisUtil.closeSqlSession();
		}
	}
	/**
	 * 有条件分页
	 */
	public List<Student> findAllByNameWithFy(String name,int start,int size) throws Exception{
		SqlSession sqlSession = null;
		try{
			sqlSession = MybatisUtil.getSqlSession();
			Map<String,Object> map = new LinkedHashMap<String, Object>();
			map.put("pname","%"+name+"%");
			map.put("pstart",start);
			map.put("psize",size);			
			return sqlSession.selectList(Student.class.getName()+".findAllByNameWithFy",map);
		}catch(Exception e){
			e.printStackTrace();
			throw e;
		}finally{
			MybatisUtil.closeSqlSession();
		}
	}
	
	public static void main(String[] args) throws Exception{
		StudentDao dao = new StudentDao();
		
		//for(int i=1;i<=10;i++){
		//	dao.add(new Student(i,"哈哈",7000D));
		//}
		
		System.out.println("--------------------第一页");
		List<Student> studentList1 = dao.findAllByNameWithFy("哈",0,3);
		for(Student s : studentList1){
			System.out.println(s.getId()+":"+s.getName()+":"+s.getSal());
		}
		System.out.println("--------------------第二页");
		List<Student> studentList2 = dao.findAllByNameWithFy("哈",3,3);
		for(Student s : studentList2){
			System.out.println(s.getId()+":"+s.getName()+":"+s.getSal());
		}
		System.out.println("--------------------第三页");
		List<Student> studentList3 = dao.findAllByNameWithFy("哈",6,3);
		for(Student s : studentList3){
			System.out.println(s.getId()+":"+s.getName()+":"+s.getSal());
		}
		
	}
}
StudentMapper.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="cn.itcast.javaee.mybatis.app10.Student">	

	<resultMap type="cn.itcast.javaee.mybatis.app10.Student" id="studentMap">
		<id property="id" column="students_id"/>
		<result property="name" column="students_name"/>
		<result property="sal" column="students_sal"/>
	</resultMap>
	
	
	<insert id="add" parameterType="cn.itcast.javaee.mybatis.app10.Student">
		insert into students(students_id,students_name,students_sal) 
		values(#{id},#{name},#{sal});
	</insert>
	
	
	<select id="findAllWithFy" parameterType="map" resultMap="studentMap">
		select students_id,students_name,students_sal 
		from students 
		limit #{pstart},#{psize}
	</select>
	
	
	<select id="findAllByNameWithFy" parameterType="map" resultMap="studentMap">
		select students_id,students_name,students_sal 
		from students 
		where students_name like #{pname}
		limit #{pstart},#{psize}
	</select>
	
	
</mapper>



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