java项目分页怎么做 java分页工具类

使用java实现分页功能

分页的实现在日常的开发中会经常遇到，编写一个分页工具类，以后可以直接引用了，呵呵。。。

1.分页工具类，封装分页信息

1 package com.student.util;
 2 import java.util.List;
 3 
 4 import com.student.entity.Person;
 5 
 6 /**
 7  * 封装分页信息
 8  * @author Administrator
 9  *
10  * @param <Person>
11  */
12 public class PageModel<E> {
13 
14     //结果集
15     private List<E> list;
16     
17     //查询记录数
18     private int totalRecords;
19     
20     //第几页
21     private int pageNo;
22     
23     //每页多少条记录
24     private int pageSize;
25     
26     //总页数
27     public int getTotalPages(){
28         return (totalRecords + pageSize -1)/pageSize;
29     }
30     
31     //首页
32     public int getTopPage(){
33         return 1;
34     }
35     
36     //上一页
37     public int getPreviousPage(){
38         if(pageNo<=1){
39             return 1;
40         }
41         return pageNo-1;
42     }
43     //下一页
44     public int getNextPage(){
45         if(pageNo>=getBottomPage()){
46             return getBottomPage();
47         }
48         return pageNo+1;
49     }
50     
51     //尾页
52     public int getBottomPage(){
53         return getTotalPages();
54     }
55     
56     public List<E> getList() {
57         return list;
58     }
59     public void setList(List<E> list) {
60         this.list = list;
61     }
62     public int getTotalRecords() {
63         return totalRecords;
64     }
65     public void setTotalRecords(int totalRecords) {
66         this.totalRecords = totalRecords;
67     }
68     public int getPageNo() {
69         return pageNo;
70     }
71     public void setPageNo(int pageNo) {
72         this.pageNo = pageNo;
73     }
74     public int getPageSize() {
75         return pageSize;
76     }
77     public void setPageSize(int pageSize) {
78         this.pageSize = pageSize;
79     }
80 
81 }

2.测试类

1 public class PageModelTest{
  2     public static void main(String[] args){
  3         int pageNo=1;
  4         int pageSize=10;
  5         findUserList(pageNo,pageSize);
  6     }
  7     /**
  8      * 分页查询
  9      * @param pageNo 第几页
 10      * @param pageSize 每页多少条记录
 11      * @return PageModel<E>
 12      */
 13     public PageModel<Person> findUserList(int pageNo,int pageSize){
 14         PageModel<Person> pageModel = null;
 15         Connection conn = null;
 16         PreparedStatement ps = null;
 17         ResultSet rs = null;
 18         //各数据库的分页语句不一样
 19         
 20         /*oracle实现分页,三层嵌套，这里10应该为pageNo*pageSize ，0为(pageNo-1)*pageSize
 21         String sql="
 22         select column1,column2,column3,column4,column5 from    
 23              (select rownum rn,column1,column2,column3,column4,column5 from
 24                  (select column1,column2,column3,column4,column5 from table_name order by column desc)
 25              where rownum<=10)
 26          where rn>0";
 27         */
 28         //mysql实现分页
 29         String sql="select * from person order by id desc limit ?,? "; 
 30         conn=DBUtil.getUtil().getConnection();
 31         try {
 32             ps=conn.prepareStatement(sql);
 33             ps.setInt(1, (pageNo-1) * pageSize);
 34             ps.setInt(2, pageSize);
 35             rs=ps.executeQuery();
 36             List<Person> personList  = new ArrayList<Person>();
 37             while(rs.next()){
 38                 Person person=new Person();
 39                 person.setName(rs.getString("stu_name"));
 40                 person.setPassword(rs.getString("stu_psw"));
 41                 person.setNumber(rs.getString("stu_number"));
 42                 person.setBirthday(rs.getDate("stu_birth"));
 43                 person.setSex(rs.getInt("stu_sex"));
 44                 person.setPolity(rs.getInt("stu_polity"));
 45                 person.setBrief(rs.getString("stu_brief"));
 46                 person.setType(rs.getInt("type"));
 47                 person.setState(rs.getInt("state"));
 48                 personList.add(person);
 49             }
 50             pageModel = new PageModel<Person>();
 51             pageModel.setList(personList);
 52             pageModel.setTotalRecords(getTotalRecords(conn));
 53             pageModel.setPageSize(pageSize);
 54             pageModel.setPageNo(pageNo);
 55         } catch (SQLException e) {
 56             // TODO Auto-generated catch block
 57             e.printStackTrace();
 58         }finally{
 59             try {
 60                 if(rs!=null){
 61                     rs.close();
 62                 }
 63                 if(ps!=null){
 64                     ps.close();
 65                 }
 66                 if(conn!=null){
 67                     conn.close();
 68                 }
 69             } catch (SQLException e) {
 70                 // TODO Auto-generated catch block
 71                 e.printStackTrace();
 72             }
 73         }
 74         return pageModel;
 75     }
 76     /**
 77      * 得到总记录数，私有方法，外部无法访问，本类中使用
 78      * @param conn
 79      * @return
 80      */
 81     private int getTotalRecords(Connection conn){
 82         PreparedStatement ps = null;
 83         ResultSet rs = null;
 84 
 85         String sql="select count(*) from person"; 
 86         
 87         conn=DBUtil.getUtil().getConnection();
 88         int count=0;
 89         try {
 90             
 91             ps=conn.prepareStatement(sql);
 92             rs=ps.executeQuery();
 93             while(rs.next()){
 94                 //此时根据sql语句查出的只有一列，否则不建议用int标识字段
 95                 count = rs.getInt(1);
 96             }
 97         } catch (SQLException e) {
 98             e.printStackTrace();
 99         }finally{
100             try {
101                 if(rs!=null){
102                     rs.close();
103                 }
104                 if(ps!=null){
105                     ps.close();
106                 }
107             } catch (SQLException e) {
108                 // TODO Auto-generated catch block
109                 e.printStackTrace();
110             }
111         }
112         return count;
113     }
114 }