JAva実装ページングツールクラス(JDBC)
1.ページングツールクラス、ページング情報のカプセル化
2.テストクラス
package com.student.util;
import java.util.List;
import com.student.entity.Person;
/**
*
* @author Administrator
*
* @param <Person>
*/
public class PageModel<E> {
//
private List<E> list;
//
private int totalRecords;
//
private int pageNo;
//
private int pageSize;
//
public int getTotalPages(){
return (totalRecords + pageSize -1)/pageSize;
}
//
public int getTopPage(){
return 1;
}
//
public int getPreviousPage(){
if(pageNo<=1){
return 1;
}
return pageNo-1;
}
//
public int getNextPage(){
if(pageNo>=getBottomPage()){
return getBottomPage();
}
return pageNo+1;
}
//
public int getBottomPage(){
return getTotalPages();
}
public List<E> getList() {
return list;
}
public void setList(List<E> list) {
this.list = list;
}
public int getTotalRecords() {
return totalRecords;
}
public void setTotalRecords(int totalRecords) {
this.totalRecords = totalRecords;
}
public int getPageNo() {
return pageNo;
}
public void setPageNo(int pageNo) {
this.pageNo = pageNo;
}
public int getPageSize() {
return pageSize;
}
public void setPageSize(int pageSize) {
this.pageSize = pageSize;
}
}
2.テストクラス
public class PageModelTest{
public static void main(String[] args){
int pageNo=1;
int pageSize=10;
findUserList(pageNo,pageSize);
}
/**
*
* @param pageNo
* @param pageSize
* @return PageModel<E>
*/
public PageModel<Person> findUserList(int pageNo,int pageSize){
PageModel<Person> pageModel = null;
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
//
//oracle , , 10 pageNo*pageSize ,0 (pageNo-1)*pageSize
//String sql="
//select column1,column2,column3,column4,column5 from
// (select rownum rn,column1,column2,column3,column4,column5 from
// (select column1,column2,column3,column4,column5 from table_name order by column desc)
// where rownum<=10)
//where rn>0";
//mysql
String sql="select * from person order by id desc limit ?,? ";
conn=DBUtil.getUtil().getConnection();
try {
ps=conn.prepareStatement(sql);
ps.setInt(1, (pageNo-1) * pageSize);
ps.setInt(2, pageSize);
rs=ps.executeQuery();
List<Person> personList = new ArrayList<Person>();
while(rs.next()){
Person person=new Person();
person.setName(rs.getString("stu_name"));
person.setPassword(rs.getString("stu_psw"));
person.setNumber(rs.getString("stu_number"));
person.setBirthday(rs.getDate("stu_birth"));
person.setSex(rs.getInt("stu_sex"));
person.setPolity(rs.getInt("stu_polity"));
person.setBrief(rs.getString("stu_brief"));
person.setType(rs.getInt("type"));
person.setState(rs.getInt("state"));
personList.add(person);
}
pageModel = new PageModel<Person>();
pageModel.setList(personList);
pageModel.setTotalRecords(getTotalRecords(conn));
pageModel.setPageSize(pageSize);
pageModel.setPageNo(pageNo);
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
try {
if(rs!=null){
rs.close();
}
if(ps!=null){
ps.close();
}
if(conn!=null){
conn.close();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return pageModel;
}
/**
* , , ,
* @param conn
* @return
*/
private int getTotalRecords(Connection conn){
PreparedStatement ps = null;
ResultSet rs = null;
String sql="select count(*) from person";
conn=DBUtil.getUtil().getConnection();
int count=0;
try {
ps=conn.prepareStatement(sql);
rs=ps.executeQuery();
while(rs.next()){
// sql , int
count = rs.getInt(1);
}
} catch (SQLException e) {
e.printStackTrace();
}finally{
try {
if(rs!=null){
rs.close();
}
if(ps!=null){
ps.close();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return count;
}
}