SSM-分页查询

1.设置好Page类

public class Page<T>{
private int pageno;

private int pageStartIndex;

private int pageSize;

private long totalRows;

private long totalPages;

private List<T> datas;

public Page(){
pageno  = 1;
pageSize = 4;    //根据需要设置
}

public Page(int pageno,int pageSize){
if(pageno < 0){
pageno = 1;}
if(pageSize < 0){
pageSize = 4;}
this.pageno = pageno;
this.pageSize = pageSize;
}

//getter && setter

public int getStartIndex(){
return (pageno-1)*pageSize;}
}

 

2.dao层

public List<User> selectCurrentPageUser(Map<String,Object> map);

 

3.mapper层

<select id="selectCurrentPageUser" resultType="xxx.xxx.xxx.User">

select *  from user limit #{pageStartIndex},#{pageSize}

</select>

4.service层

 

public Page<User> findCurrenPage(int pageno){

Page<User> page = new Page<>(pageno,PAGE_SIZE);

int totalRows = dao.selectTotalRows();

page.setTotalRows(totalRows);

int pageStartIndex = page.getPageStartIndex();

int pageSize = page.getSize();

Map<String,Object> map = new HashMap<>();

map.put("pageStartIndex",pageStartIndex);

map.put("pageSize",pageSize);

List<User> datas = dao.selectCurrentPageUser(map);

page.setDatas(datas);

return page;

}

 

 

5.controller层

<select id="selectCurrentPageUser" resultType="xxx.xxx.xxx.User">

select *  from user limit #{pageStartIndex},#{pageSize}

</select>