java web實(shí)現(xiàn)分頁查詢實(shí)例方法

發(fā)布時(shí)間：2020-10-03 13:12:11 來源：腳本之家閱讀：178 作者：laozhang 欄目：編程語言

Javaweb分頁技術(shù)實(shí)現(xiàn)

分頁技術(shù)就是通過SQL語句(如下)來獲取數(shù)據(jù)，具體實(shí)現(xiàn)看下面代碼

//分頁查詢語句
select * from 表名 where limit page , count;
和
//獲取表中的總數(shù)據(jù)，確定頁數(shù)
select count(*) from 表名;

不說廢話直接上代碼

前端代碼：

<!DOCTYPE html>
<html>
<head>
 <meta charset="UTF-8">
 <title>Title</title>
 <script src="js/jquery-3.3.1.js"></script>
 <link rel="stylesheet" href="css/bootstrap.min.css" rel="external nofollow" >
</head>
<body>
 
<div>
 <div class="row clearfix">
  <div class="col-md-12 column">
   <table class="table table-bordered table-hover">
    <thead>
    <tr>
     <th>City_ID</th>
     <th>City_EN</th>
     <th>City_CN</th>
     <th>Country_code</th>
     <th>Country_EN</th>
     <th>Country_CN</th>
     <th>Province_EN</th>
     <th>Province_CN</th>
    </tr>
    </thead>
    <tbody id="tbody">
 
    </tbody>
   </table>
   <!--分頁-->
   第<span id="paging">1</span>頁/
   共<span id="countPage">1</span>頁/
   <a id="homePage">Home</a>/
   <a id="prevPage">Prev</a>/
   <a id="nextPage">Next</a>/
   轉(zhuǎn)到第：
   <input type="text"  id="pageNum">
   頁
   <a id="goPage">Go</a>
 
 
  </div>
 </div>
</div>
</body>
<script>
 $(function () {
  //頁面初始化 （顯示第一頁）
  selectPage(1);
  home();
  prev();
  next();
  goPage();
 })
 function selectPage(pageCode) {
  //分頁查詢 pageCode：頁數(shù)
  $.ajax("getCity",{
   type:"get",
   data:{"currenPage":pageCode},
   success:function (data) {
    $("#tbody").html("");
    //總頁數(shù)
    $("#countPage").text(data.totalPage);
 
    $.each(data.pageData,function (index,obj) {
     var clazz="";
     if(index%2==0){
      clazz="success";
     }
     $("#tbody").append(
      "<tr class='"+clazz+"'>\n" +
      "<td>"+obj.cityId+"</td>\n" +
      "<td>"+obj.cityEn+"</td>\n" +
      "<td>"+obj.cityCn+"</td>\n" +
      "<td>"+obj.countryCode+"</td>\n" +
      "<td>"+obj.countryEn+"</td>\n" +
      "<td>"+obj.countryCn+"</td>\n" +
      "<td>"+obj.provinceEn+"</td>\n" +
      "<td>"+obj.provinceCn+"</td>\n" +
      "</tr>"
     );
    })
 
   }
  });
 }
 //第一頁
 function home() {
  $("#homePage").on("click",function () {
   $("#paging").text(1);
   selectPage(1);
  })
 }
 
 //上一頁
 function prev() {
  $("#prevPage").on("click",function () {
   var prevText=$("#paging").text();
   var prevNum=parseInt(prevText);
   prevNum=prevNum-1;
   if(prevNum<=1){
    selectPage(1);
    $("#paging").text(1);
    return;
   }
   $("#paging").text(prevNum);
   selectPage(prevNum);
  })
 }
 //下一頁
 function next() {
  $("#nextPage").on("click",function () {
   //獲取文本的值 頁數(shù)
   var prevText=$("#paging").text();
   //類型轉(zhuǎn)換
   var prevNum=parseInt(prevText);
   //總頁數(shù)
   var countText=$("#countPage").text();
   //類型轉(zhuǎn)換
   var countNum = parseInt(countText);
   //頁數(shù)加1
   prevNum=prevNum+1;
   //判斷超出了總頁碼
   if(prevNum>=countNum){
    selectPage(countNum);
    $("#paging").text(countNum);
    return;
   }
   //設(shè)置網(wǎng)頁增加的值
   $("#paging").text(prevNum);
   //調(diào)用分頁查詢
   selectPage(prevNum);
  })
 }
 //去到幾頁
 function goPage() {
  $("#goPage").on("click",function () {
   var pageNum=parseInt($("#pageNum").val());
   var countPage=parseInt($("#countPage").text())
   //判斷超出了總頁碼
   if(pageNum>=countPage){
    selectPage(countPage);
    $("#paging").text(countPage);
    $("#pageNum").val(countPage);
    return;
   }
   //判斷低于了總頁碼
   if(pageNum<=1){
    selectPage(1);
    $("#paging").text(1);
    $("#pageNum").val(1);
    return;
   }
   selectPage(pageNum);
   $("#paging").text(pageNum);
  })
 }
 
</script>
</html>

后臺(tái)servlet代碼：

/**
 * @author hh
 * @Date 2018/9/12
 */
@WebServlet("/getCity")
public class PageServlet extends HttpServlet {
 @Override
 protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
  //獲取當(dāng)前頁參數(shù)，第一次訪問為空
  String currPage = req.getParameter("currenPage");
  // 判斷，如果為空，則設(shè)置為1
  if (currPage == null || "".equals(currPage.trim())) {
   currPage = "1";
  }
  //調(diào)用service返回分頁類實(shí)例
  PageBean<City> pageBean=new PageService().getPage(currPage);
  //設(shè)置相應(yīng)文本類型
  resp.setContentType("application/json;charset=utf-8");
  //響應(yīng)前端
  resp.getWriter().print(new Gson().toJson(pageBean));
 }
}

City 實(shí)體類：

package edu.nf.demo.entity;
 
/**
 * @author hh
 * @Date 2018/9/12
 */
public class City {
 private String cityId;
 private String cityEn;
 private String cityCn;
 private String countryCode;
 private String countryEn;
 private String countryCn;
 private String provinceEn;
 private String provinceCn;
 public String getCityId() {
  return cityId;
 }
 public void setCityId(String cityId) {
  this.cityId = cityId;
 }
 public String getCityEn() {
  return cityEn;
 }
 public void setCityEn(String cityEn) {
  this.cityEn = cityEn;
 }
 
 public String getCityCn() {
  return cityCn;
 }
 public void setCityCn(String cityCn) {
  this.cityCn = cityCn;
 }
 public String getCountryCode() {
  return countryCode;
 }
 public void setCountryCode(String countryCode) {
  this.countryCode = countryCode;
 }
 public String getCountryEn() {
  return countryEn;
 }
 public void setCountryEn(String countryEn) {
  this.countryEn = countryEn;
 }
 public String getCountryCn() {
  return countryCn;
 }
 
 public void setCountryCn(String countryCn) {
  this.countryCn = countryCn;
 }
 
 public String getProvinceEn() {
  return provinceEn;
 }
 
 public void setProvinceEn(String provinceEn) {
  this.provinceEn = provinceEn;
 }
 
 public String getProvinceCn() {
  return provinceCn;
 }
 
 public void setProvinceCn(String provinceCn) {
  this.provinceCn = provinceCn;
 }
}

自己寫的一個(gè)類，專門用于分頁查詢用的：

package edu.nf.demo.entity;
 
import java.util.List;
 
/**
 * @author hh
 * @Date 2018/9/12
 */
public class PageBean<T> {
 /**
  * 當(dāng)前頁， 默認(rèn)顯示第一頁
  */
 private Integer currntPage = 1;
 /**
  * 查詢返回的行數(shù)（每頁顯示的行數(shù)），默認(rèn)每頁顯示10行
  */
 private int pageCount = 10;
 /**
  * 總記錄數(shù)
  */
 private int totalCount;
 /**
  * 總頁數(shù) = 總記錄數(shù)/每頁顯示的行數(shù)（+1）
  */
 private int totalPage;
 /**
  * 分頁查詢的數(shù)據(jù),運(yùn)用泛型，可以重復(fù)利用
  */
 private List<T> pageData;
 
 public int getTotalPage() {
  if (totalCount % pageCount == 0) {
   totalPage = totalCount / pageCount;
  } else {
   totalPage = totalCount / pageCount + 1;
  }
  return totalPage;
 }
 
 public void setTotalPage(int totalPage) {
  this.totalPage = totalPage;
 }
 
 public int getCurrntPage() {
  return currntPage;
 }
 
 public void setCurrntPage(int currntPage) {
  this.currntPage = currntPage;
 }
 
 public int getPageCount() {
  return pageCount;
 }
 
 public void setPageCount(int pageCount) {
  this.pageCount = pageCount;
 }
 
 public int getTotalCount() {
  return totalCount;
 }
 
 public void setTotalCount(int totalCount) {
  this.totalCount = totalCount;
 }
 
 
 public List<T> getPageData() {
  return pageData;
 }
 
 public void setPageData(List<T> pageData) {
  this.pageData = pageData;
 }
}

后臺(tái)service，邏輯業(yè)務(wù)層：

/**
 * @author hh
 * @Date 2018/9/12
 */
public class PageService {
 
 public PageBean getPage(String currPage){
  //類型轉(zhuǎn)換 當(dāng)前頁數(shù)
  Integer currenPage = Integer.valueOf(currPage);
  //實(shí)例化分頁類
  PageBean<City> pageBean = new PageBean();
  //實(shí)例化CityDaoImpl類
  CityDaoImpl cityDao=new CityDaoImpl();
 
  //數(shù)據(jù)庫第幾行開始查詢
  int startPage=(currenPage-1)*pageBean.getPageCount();
  //查詢多少行數(shù)據(jù) 分頁類里默認(rèn)30行
  int selectCount=pageBean.getPageCount();
  //查詢數(shù)據(jù)庫獲取分頁返回的數(shù)據(jù) : select * from regional_info limit startPage,selectCount
  List<City> list=cityDao.listCity(startPage,selectCount);
  //獲取總數(shù)
  int cityCount=cityDao.getCityCount();
  //設(shè)置查詢的數(shù)據(jù)
  pageBean.setPageData(list);
  //共多少行
  pageBean.setTotalCount(cityCount);
  //設(shè)置總頁數(shù)
  pageBean.setTotalPage(cityCount/pageBean.getPageCount()+1);
  return pageBean;
 }
}

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java web實(shí)現(xiàn)分頁查詢實(shí)例方法

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