当前位置：网站首页>JSP - paging

JSP - paging

2022-07-01 06:57:00 【allway2】

Introduce

JavaServer Pages or JSP It's based on Java Technology , For creating dynamic web pages .JSP Use special JSP Tag help in HTML File insert Java Code . for example , Displays the first five even numbers JSP The page will look like this ,

<html>    <head>        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">        <title>JSP Page</title>    </head>    <style>        body{            padding: 50px;        }    </style>    <body>        <%            for(int i=0;i<10;i++){                if(i%2==0)                    out.print("<h1>Even No: "+i+"</h1>");             }        %>    </body> </html>

Pagination

Suppose there are multiple records in our database . under these circumstances , We use paging to break down records into more readable bits , This is true for both users and processors , Because a single page with multiple records may take time to load and users may be tired . Let's look at an example of paging ,

We will be in Netbeans Create our project in , Use XAMPP The server is connected to our SQL database . The following is the project structure .

index.jsp

<%@page contentType="text/html" pageEncoding="UTF-8"%> <!DOCTYPE html> <html>    <head>        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">        <title>JSP Page</title>    </head>    <body>        <a href="view.jsp?page=1">View Employees</a>     </body> </html>

view.jsp

<%@page contentType="text/html" pageEncoding="UTF-8"%> <!DOCTYPE html> <html>    <head>        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">        <title>JSP Page</title>    </head>    <style>        body{            padding: 50px;        }    </style>    <body>        <%@ page import="java.util.*,Emp.*,EmpDao.*" %>         <%         String spageid=request.getParameter("page");         int pageid=Integer.parseInt(spageid);         int total=5;        if(pageid!=1){             pageid=pageid-1;             pageid=pageid*total+1;         }         List<Emp> list=EmpDao.getRecords(pageid,total);         out.print("<h1>Page No: "+spageid+"</h1>");         out.print("<table border='1' cellpadding='4' width='60%'>");         out.print("<tr><th>Id</th><th>Name</th><th>Salary</th>");         for(Emp e:list){             out.print("<tr><td>"+e.getId()+"</td><td>"+e.getName()+"</td><td>"+e.getSalary()+"</td></tr>");         }         out.print("</table>");         %>         <a href="view.jsp?page=1">1</a>         <a href="view.jsp?page=2">2</a>         <a href="view.jsp?page=3">3</a>    </body> </html>

Emp.java

package Emp; /** * * @author 91963 */ public class Emp {    private int id;     private String name;     private float salary;        public void setId(int aInt) {        id = aInt;    }    public void setName(String string) {        name = string;    }    public void setSalary(float aFloat) {        salary = aFloat;    }       public int getId(){        return id;    }        public String getName(){        return name;    }        public float getSalary(){        return salary;    } }

EmpDao.java

package EmpDao; import java.sql.*;  import Emp.*; import java.util.ArrayList;  import java.util.List;   /** * * @author 91963 */ public class EmpDao {    public static Connection getConnection(){         Connection con=null;         try{             Class.forName("com.mysql.jdbc.Driver");             con=DriverManager.getConnection("jdbc:mysql://localhost:3306/test","root","");         }catch(ClassNotFoundException | SQLException e){System.out.println(e);}         return con;     }     public static List<Emp> getRecords(int start,int total){         List<Emp> list=new ArrayList<>();         try        {             try (Connection con = getConnection()) {                PreparedStatement ps=con.prepareStatement("select * from emp limit "+(start-1)+","+total);                ResultSet rs=ps.executeQuery();                while(rs.next()){                    Emp e=new Emp();                    e.setId(rs.getInt(1));                    e.setName(rs.getString(2));                    e.setSalary(rs.getFloat(3));                    list.add(e);                } }         }catch(Exception e){System.out.println(e);}         return list;     }  }

Output

common problem

What is? JSP？
JavaServer Pages or JSP It's based on Java Technology , For creating dynamic web pages .JSP Use the only JSP Tag help in HTML File insert Java Code .
What is pagination ？
Paging is used to divide records into more convenient readable bits , This is true for both users and processors , Because a single page with multiple records may take time to load and users may be tired .

Key points

This blog covers JavaServer Pages All the necessary points for paging in , The function and the method of paging application are discussed in detail . And it's in JavaServer Pages In the implementation of .

原网站

版权声明
本文为[allway2]所创，转载请带上原文链接，感谢
https://yzsam.com/2022/182/202207010645321804.html