Mysql分页、SSM项目分页实战
作者：互联网
一、Mysql分页
记住几个万年不变的公式就完了
（1）limit分页公式：limit (curPage-1)*pageSize,pageSize curPage是当前第几页；pageSize是一页多少条记录 sql语句： select * from student limit (curPage-1)*pageSize,pageSize;
（2）总页数公式： int totalPageNum = (totalRecord +pageSize - 1) / pageSize; totalRecord是总记录数；pageSize是一页分多少条记录
（3）总记录数： count( * ) sql语句： select count( * ) from student；
二、SSM项目分页实战
1、首先，我们先准备一个分页用到的工具类
public class PageUtil<T> {
private int pageIndex;//当前页码
private int pageSize; //页面大小
private int totalcount; //总条数
private int pageCount; //总页数
private List<T> records; //分页的数据
private int numberStart; //开始序号
private int numberEnd; //结束序号
private List<Integer> numbers=new ArrayList<Integer>(); //序号
public PageUtil(int pageIndex, int pageSize, int totalcount, List<T> records) {
this.pageIndex = pageIndex;
this.pageSize = pageSize;
this.totalcount = totalcount;
this.records = records;
//人工计算总页数
this.pageCount=(this.totalcount%this.pageSize==0)?(this.totalcount/this.pageSize):(this.totalcount/this.pageSize+1);
//给序号赋值
if(this.pageCount<=10){
this.numberStart=1;
this.numberEnd=this.pageCount;
}else{
this.numberStart=this.pageIndex-4;
this.numberEnd=this.pageIndex+5;
if(this.numberStart<1){
this.numberStart=1;
this.numberEnd=10;
}
if(this.numberEnd>this.pageCount){
this.numberStart=this.pageCount-9;
this.numberEnd=this.pageCount;
}
}
for(int i=numberStart;i<=numberEnd;i++){
numbers.add(i);
}
}
public int getPageIndex() {
return pageIndex;
}
public void setPageIndex(int pageIndex) {
this.pageIndex = pageIndex;
}
public int getPageSize() {
return pageSize;
}
public void setPageSize(int pageSize) {
this.pageSize = pageSize;
}
public int getTotalcount() {
return totalcount;
}
public void setTotalcount(int totalcount) {
this.totalcount = totalcount;
}
public int getPageCount() {
return pageCount;
}
public void setPageCount(int pageCount) {
this.pageCount = pageCount;
}
public List<T> getRecords() {
return records;
}
public void setRecords(List<T> records) {
this.records = records;
}
public int getNumberStart() {
return numberStart;
}
public void setNumberStart(int numberStart) {
this.numberStart = numberStart;
}
public int getNumberEnd() {
return numberEnd;
}
public void setNumberEnd(int numberEnd) {
this.numberEnd = numberEnd;
}
public List<Integer> getNumbers() {
return numbers;
}
public void setNumbers(List<Integer> numbers) {
this.numbers = numbers;
}
}
2、看一下我们数据库的数据
3、运行我们的SSM项目，打开页面，请求Controller
4、看一下，我们的Controller
5、Service层就不带大家看了，直接来到持久层
6、返回到我们的页面，主要看参数那一块是怎么取值的，这个SSM项目没有用到Jsp页面，用到的是thymeleaf模板