这个问题折腾了好长时间,原帖在这http://www.cnblogs.com/xinxin1994/p/6243979.html
我这是修改了一个小错误,就是显示页数的问题
原帖都放在了一个包中,自己可以分,我这还是在一个包里
数据库
/*
Navicat MySQL Data Transfer
Source Server : localhost_3306
Source Server Version : 50720
Source Host : localhost:3306
Source Database : newshopping
Target Server Type : MYSQL
Target Server Version : 50720
File Encoding : 65001
Date: 2018-06-30 14:15:10
*/
SET FOREIGN_KEY_CHECKS=0;
-- ----------------------------
-- Table structure for student
-- ----------------------------
DROP TABLE IF EXISTS `student`;
CREATE TABLE `student` (
`id` int(255) DEFAULT NULL,
`name` varchar(255) DEFAULT NULL,
`age` int(255) DEFAULT NULL,
`sex` varchar(255) DEFAULT NULL,
`birth` date DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
-- ----------------------------
-- Records of student
-- ----------------------------
INSERT INTO `student` VALUES ('1', '12', '12', '12', '2015-01-01');
INSERT INTO `student` VALUES ('2', '12', '13', '14', '2016-07-07');
INSERT INTO `student` VALUES ('3', '12', '13', '16', '2018-09-08');
INSERT INTO `student` VALUES ('4', '12', '13', '16', '2018-08-08');
INSERT INTO `student` VALUES ('5', '12', '13', '16', '2018-09-09');
INSERT INTO `student` VALUES ('5', '12', '13', '16', '2018-08-08');
INSERT INTO `student` VALUES ('5', '12', '13', '16', '2018-08-08');
INSERT INTO `student` VALUES ('5', '12', '13', '16', '2018-08-08');
INSERT INTO `student` VALUES ('5', '12', '13', '16', '2018-08-08');
INSERT INTO `student` VALUES ('5', '12', '13', '16', '2018-08-08');
INSERT INTO `student` VALUES ('5', '12', '13', '16', '2018-08-08');
INSERT INTO `student` VALUES ('5', '12', '13', '16', '2018-08-08');
INSERT INTO `student` VALUES ('5', '12', '13', '16', '2018-08-08');
INSERT INTO `student` VALUES ('5', '5', '12', '13', '2016-09-09');
INSERT INTO `student` VALUES ('5', '12', '13', '16', '2018-08-08');
INSERT INTO `student` VALUES ('5', '12', '13', '16', '2018-08-08');
Student.java
package test;
import java.util.Date;
public class Student {
private int id;
private String name;
private int age;
private String sex;
private Date birth;
public Student() {
super();
}
public Student(int id, String name, int age, String sex, Date birth) {
super();
this.id = id;
this.name = name;
this.age = age;
this.sex = sex;
this.birth = birth;
}
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 int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public Date getBirth() {
return birth;
}
public void setBirth(Date birth) {
this.birth = birth;
}
}
PageView.java
package test;
import java.util.List;
public class PageView {
private List<Student> records;// 记录
private Long totalrecordnumber;// 总记录数
private Integer startindex;// 第一页
private Integer endindex;// 最后一页
private Integer totalpagenumber;// 总页数
private Integer currentpage;// 当前页
public PageView(List<Student> records, Long totalrecordnumber, int currentpage, int maximum, int viewperpage)
// 构造函数
{
this.records = records;
this.totalrecordnumber = totalrecordnumber;
this.currentpage = currentpage;
totalpagenumber = (int) (totalrecordnumber % maximum == 0 ? totalrecordnumber / maximum
: totalrecordnumber / maximum + 1);// 获得总页数
setIndex(currentpage, viewperpage, totalpagenumber);
}
public List<Student> getRecords() {
return records;
}
public Long getTotalrecordnumber() {
return totalrecordnumber;
}
public Integer getStartindex() {
return startindex;
}
public Integer getEndindex() {
return endindex;
}
public Integer getTotalpagenumber() {
return totalpagenumber;
}
public Integer getCurrentpage() {
return currentpage;
}
// 获得总页数 显示页数 当前页数 第一页 最后一页
public void setIndex(int currentpage, int viewperpage, int totalpagenumber) {
if (viewperpage >= totalpagenumber) {
startindex = 1;
endindex = totalpagenumber;
} else {
if (currentpage <= viewperpage / 2) {
startindex = 1;
endindex = viewperpage;
} else if ((currentpage + viewperpage / 2) > totalpagenumber) {
startindex = totalpagenumber - viewperpage + 1;
endindex = totalpagenumber;
} else {
startindex = currentpage - (viewperpage - 1) / 2;
endindex = currentpage + viewperpage / 2;
}
}
}
}
PageServlet.java
package test;
import java.io.IOException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class PageServlet extends HttpServlet {
public static Statement returnConn() throws SQLException{
// String name="com.mysql.jdbc.Driver";
String url="jdbc:mysql://127.0.0.1/newshopping";
String user="root";
String password="123123";
//加载驱动
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//连接数据库
Connection conn=DriverManager.getConnection(url, user, password);
Statement st=conn.createStatement();
return st;
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//showone(request,response);
try {
showtwo(request,response);
} catch (SQLException e) {
e.printStackTrace();
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
public void showone(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{
try {
Statement st=returnConn();
String sql="select * from student";
ResultSet rs=st.executeQuery(sql);
List<Student> list=new ArrayList<Student>();
while(rs.next()){
int id=rs.getInt("id");
String name=rs.getString("name");
int age=rs.getInt("age");
String sex=rs.getString("sex");
Date birth=rs.getDate("birth");
Student stu=new Student(id,name,age,sex,birth);
list.add(stu);
}
//response.sendRedirect("studentlist.jsp");
request.setAttribute("list", list);
request.getRequestDispatcher("studentlist.jsp").forward(request, response);
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public void showtwo(HttpServletRequest request, HttpServletResponse response) throws SQLException, ServletException, IOException{
// 当前是第几页
String currentpageStr = request.getParameter("currentpage") == null ? "1"
: request.getParameter("currentpage");
int currentpage = Integer.parseInt(currentpageStr);
// 每页显示多少条
int maximum = 5;
// 可以显示多少页
int viewperpage = 5;
Statement st=returnConn();
String sql="select * from student limit "+ (currentpage - 1) * maximum + "," + maximum;
ResultSet rs=st.executeQuery(sql);
List<Student> list=new ArrayList<Student>();
while(rs.next()){
int id=rs.getInt("id");
String name=rs.getString("name");
int age=rs.getInt("age");
String sex=rs.getString("sex");
Date birth=rs.getDate("birth");
Student stu=new Student(id,name,age,sex,birth);
list.add(stu);
}
String sql2="select * from student";
ResultSet rs2=st.executeQuery(sql2);
int count=0;
while(rs2.next()){
count++;
}
long totalrecordnumber=count;
// 将数据都封装到pageView
PageView pageView =new PageView(list, totalrecordnumber, currentpage, maximum, viewperpage);
// PageView<Student> pageView = new PageView<Student>(records,totalrecordnumber, currentpage, maximum, viewperpage);
request.setAttribute("pageView", pageView);
request.setAttribute("list", list);
request.getRequestDispatcher("studentlist.jsp").forward(request, response);
}
}
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN" "http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>
<servlet>
<servlet-name>PageServlet</servlet-name>
<display-name>This is the display name of my J2EE component</display-name>
<description>This is the description of my J2EE component</description>
<servlet-class>test.PageServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>PageServlet</servlet-name>
<url-pattern>/PageServlet</url-pattern>
</servlet-mapping>
</web-app>
MyJsp.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'MyJsp.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<form action="PageServlet" method="get">
<input type="submit" value="提交">
</from>
</body>
</html>
studentlist.jsp
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@ page import="test.*" %>
<%@ page isELIgnored="false" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<script type="text/javascript">
function topage(currentpage) {
var form = document.forms[0];
form.currentpage.value = currentpage;
form.submit();
}
</script>
</head>
<body>
<form>
<input type="hidden" name="currentpage" />
<table align="center" style="width: 60%;" border="1">
<tr>
<th>学生编号</th>
<th>学生姓名</th>
<th>学生年龄</th>
<th>学生性别</th>
<th>学生生日</th>
</tr>
<c:forEach items="${requestScope.list}" var="list">
<tr>
<td>${list.id }</td>
<td>${list.name }</td>
<td>${list.age }</td>
<td>${list.sex }</td>
<td>${list.birth}</td>
</tr>
</c:forEach>
</table>
<div align="right" style="width: 80%">
<c:forEach begin="${pageView.startindex}" end="${pageView.endindex}"
var="wp">
<c:if test="${pageView.currentpage==wp}">
<b>[${wp}]</b>
</c:if>
<c:if test="${pageView.currentpage!=wp}">
<a href="javascript:topage('${wp}')">[${wp}]</a>
</c:if>
</c:forEach>
<!-- ${pageView.totalrecordnumber} 本来他写错了 -->
总共${pageView.totalpagenumber}页
</div>
</form>
</body>
</html>
运行结果:结束!