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Java實(shí)現(xiàn)分頁代碼

更新時(shí)間：2019年09月08日 15:33:50 作者：小小的程序蟲

這篇文章主要為大家詳細(xì)介紹了Java實(shí)現(xiàn)分頁代碼，提高查詢效率,具有一定的參考價(jià)值，感興趣的小伙伴們可以參考一下

在項(xiàng)目中，分頁是一個(gè)項(xiàng)目中必不可少的，它可以防止我們從數(shù)據(jù)庫中進(jìn)行大量數(shù)據(jù)查詢時(shí)速度變慢，提高我們的查詢效率。

1、定義分頁模型：PageModel

 package com.common.page; 
 
 import java.util.List; 
 
 /** 
 * 封裝分頁信息 
 * @author Administrator 
 * 
 */ 
 public class PageModel<E> { 
 
 //結(jié)果集 
 private List<E> list; 
  
 //查詢記錄數(shù) 
 private int totalRecords; 
  
 //每頁多少條數(shù)據(jù) 
 private int pageSize; 
  
 //第幾頁 
 private int pageNo; 
  
 /** 
  * 總頁數(shù) 
  * @return 
  */ 
 public int getTotalPages() { 
  return (totalRecords + pageSize - 1) / pageSize; 
 } 
  
 /** 
  * 取得首頁 
  * @return 
  */ 
 public int getTopPageNo() { 
  return 1; 
 } 
  
 /** 
  * 上一頁 
  * @return 
  */ 
 public int getPreviousPageNo() { 
  if (pageNo <= 1) { 
  return 1; 
  } 
  return pageNo - 1; 
 } 
  
 /** 
  * 下一頁 
  * @return 
  */ 
 public int getNextPageNo() { 
  if (pageNo >= getBottomPageNo()) { 
  return getBottomPageNo(); 
  } 
  return pageNo + 1; 
 } 
  
 /** 
  * 取得尾頁 
  * @return 
  */ 
 public int getBottomPageNo() { 
  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 getPageSize() { 
  return pageSize; 
 } 
 
 public void setPageSize(int pageSize) { 
  this.pageSize = pageSize; 
 } 
 
 public int getPageNo() { 
  return pageNo; 
 } 
 
 public void setPageNo(int pageNo) { 
  this.pageNo = pageNo; 
 } 
 }

2、分頁測試：在MySQL中建立admin表，里面有字段id、name、password

3、簡歷Admin的實(shí)體bean類：

 package com.common.page; 
 
 public class Admin { 
 private int id; 
 private String name; 
 private String password; 
 public int getId() { 
  return id; 
 } 
 public void setId(int id) { 
  this.id = id; 
 } 
 public String getName() { 
  return name; 
 } 
 public void setName(String name) { 
  this.name = name; 
 } 
 public String getPassword() { 
  return password; 
 } 
 public void setPassword(String password) { 
  this.password = password; 
 } 
 
 }

4、測試調(diào)用：

 package com.common.page; 
 
 import java.sql.Connection; 
 import java.sql.PreparedStatement; 
 import java.sql.ResultSet; 
 import java.sql.SQLException; 
 import java.util.ArrayList; 
 import java.util.List; 
 
 import com.common.db.DbUtil; 
 
 public class Client { 
 public static PageModel findAdmins(int pageNo,int pageSize){ 
  Connection conn=DbUtil.getConnection(); 
  String sql="select * from admin limit ?,?"; 
  PageModel pageModel=null; 
  PreparedStatement pstm=null; 
  ResultSet rs=null; 
  Admin admin=null; 
  List<Admin> list=new ArrayList<Admin>(); 
  try { 
  pstm=conn.prepareStatement(sql); 
  pstm.setInt(1, (pageNo-1)*pageSize); 
  pstm.setInt(2, pageNo*pageSize); 
  rs=pstm.executeQuery();; 
  while(rs.next()){ 
   admin=new Admin(); 
   admin.setId(rs.getInt("a_id")); 
   admin.setName(rs.getString("a_name")); 
   admin.setPassword(rs.getString("a_pwd")); 
   list.add(admin); 
  } 
  ResultSet rs2=pstm.executeQuery("select count(*) from admin"); 
  int total=0; 
  if(rs2.next()){ 
   total=rs2.getInt(1); 
  } 
  pageModel=new PageModel(); 
  pageModel.setPageNo(pageNo); 
  pageModel.setPageSize(pageSize); 
  pageModel.setTotalRecords(total); 
  pageModel.setList(list); 
  } catch (SQLException e) { 
  e.printStackTrace(); 
  }finally{ 
  DbUtil.close(conn); 
  DbUtil.close(pstm); 
  DbUtil.close(rs); 
  } 
  return pageModel; 
 } 
  
 public static void main(String[] args) { 
  PageModel pageModel=Client.findAdmins(2,4); 
  List<Admin> list=pageModel.getList(); 
  for(Admin a:list){ 
  System.out.print("ID:"+a.getId()+",用戶名:"+a.getName()+",密碼:"+a.getPassword()); 
  System.out.println(); 
  } 
  System.out.print("當(dāng)前頁:"+pageModel.getPageNo()+" "); 
  System.out.print("共"+pageModel.getTotalPages()+"頁 "); 
  System.out.print("首頁:"+pageModel.getTopPageNo()+" "); 
  System.out.print("上一頁:"+pageModel.getPreviousPageNo()+" "); 
  System.out.print("下一頁:"+pageModel.getNextPageNo()+" "); 
  System.out.print("尾頁:"+pageModel.getBottomPageNo()+" "); 
  System.out.print("共"+pageModel.getTotalRecords()+"條記錄"); 
  System.out.println(); 
 } 
 
 }

這樣分頁效果就實(shí)現(xiàn)了，我們要實(shí)現(xiàn)分頁效果，只要傳入相應(yīng)的參數(shù)和相應(yīng)的數(shù)據(jù)庫執(zhí)行語句即可實(shí)現(xiàn)，希望大家能靈活運(yùn)用。

以上就是本文的全部內(nèi)容，希望對(duì)大家的學(xué)習(xí)有所幫助，也希望大家多多支持腳本之家。

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