1、web工程的整体结构
2、Eclipse中tld文件的构建方法3、编码
package mytags;
import java.io.IOException;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.TagSupport;
public class PagerTag extends TagSupport {
/**
*
*/
private static final long serialVersionUID = -3066943125964706748L;
private String url; //表单提交地址
private int recordCount; //记录总数
private int pageNo; //当前页码
private int pageSize; //页面容量
//标签体的主体方法
@Override
public int doStartTag() throws JspException {
// TODO Auto-generated method stub
//总页数
int pageCount=(recordCount+pageSize-1)/pageSize;
if(pageNo>pageCount){
pageNo=pageCount;
}
if(pageNo<0){
pageNo=1;
}
//提交到标签体的表单及脚本内容
StringBuffer sb=new StringBuffer();
sb.append("<div class=\"pagination\">");
//当action=“”时，表示不刷新页面，只更新表单内容
sb.append("<form action=\"\" method=\"post\" name=\"qPagerForm\">\r\n");
//传递当前页码的隐式参数
sb.append("<input type=\"hidden\" name=\"pageNo\" value=")
.append(pageNo).append(">");
//是否显示“上一页”链接
if(pageNo>1){
sb.append("<a href=\"javascript:void(null)\" onclick=\"turnOverPage("
+ (pageNo-1) + ")\">");
sb.append("pre");
sb.append("</a>");
}
//是否显示当前页前面的"..."，以及其它前面的显示逻辑
int start=1;
if(pageNo>4){
start=pageNo-1;
sb.append("<a href=\"javascript:void(null)\" onclick=\"turnOverPage(1)\">");
sb.append("1");
sb.append("</a>");
sb.append("<a href=\"javascript:void(null)\" onclick=\"turnOverPage(2)\">");
sb.append("2");
sb.append("</a>");
sb.append("…");
}
int end=pageNo+1;
if(end>pageCount){
end=pageCount;
}
for(int i=start;i<=end;i++){
if(i==pageNo){
sb.append("<span class=\"current\">")
.append(pageNo)
.append("</span>");
}else{
sb.append("<a href=\"javascript:void(null)\" onclick=\"turnOverPage(")
.append(i).append(")\">").append(i).append("</a>");
}
}
//当前页面后面的显示逻辑
if(end<pageCount-2){
sb.append("…");
}
if(end<pageCount-1){
sb.append("<a href=\"javascript:void(null)\" onclick=\"turnOverPage(")
.append(pageCount-1).append(")\">").append(pageCount-1).append("</a>");
}
if(end<pageCount){
sb.append("<a href=\"javascript:void(null)\" onclick=\"turnOverPage(")
.append(pageCount).append(")\">").append(pageCount).append("</a>");
//显示”下一页“链接2
sb.append("<a href=\"javascript:void(null)\" onclick=\"turnOverPage(")
.append(pageNo+1).append(")\">").append("next").append("</a>");
}
sb.append("</form></div>");
//翻页脚本函数，主要作用：
//（1）向TestPagerServlet提交跳转页码，更新条目内容的显示
//（2）更新翻页标签的显示
//脚本函数是隐式的，不会显示
sb.append("<script language=\"javascript\">\r\n");
sb.append("function turnOverPage(no){\r\n");
//脚本与表单属于同一文档，下面是获取表单的方法
sb.append("var qForm=document.qPagerForm;\r\n");
sb.append("if(no>").append(pageCount)
.append("){no=")
.append(pageCount)
.append(";}\r\n");
sb.append("if(no<1){no=1;}\r\n");
sb.append("qForm.pageNo.value=no;\r\n")
.append("qForm.action=\"").append(url).append("\";");
sb.append("qForm.submit();").append("\r\n}");
sb.append("</script>");
try {
pageContext.getOut().println(sb.toString());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return SKIP_BODY;
}
public void setRecordCount(int num){
recordCount=num;
}
public void setPageNo(int num){
pageNo=num;
}
public void setPageSize(int num){
pageSize=num;
}
public void setUrl(String str){
url=str;
}
}
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Servlet implementation class TestPagerTagServlet
*/
@WebServlet("/TestPagerTagServlet")
public class TestPagerTagServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private static final int PAGE_SIZE=10;
private List<String> datas;
/**
* @see HttpServlet#HttpServlet()
*/
public TestPagerTagServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
doPost(request, response);
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
int pageSize= PAGE_SIZE;
request.setAttribute("pageSize", pageSize);
int recordCount=datas.size();
//获取当前页码
String no=request.getParameter("pageNo");
int pageNo=1;
if(!"".equals(no) && no!=null){
pageNo=Integer.parseInt(no);
}
request.setAttribute("recordCount",recordCount);
request.setAttribute("pageNo", pageNo);
int s=(pageNo-1)*pageSize;
int e=s+pageSize;
if(e>recordCount){
e=recordCount;
}
List<String> subdatas=datas.subList(s, e);
request.setAttribute("subdatas", subdatas);
request.getRequestDispatcher("pager.jsp").forward(request, response);
}
@Override
public void init() throws ServletException {
// TODO Auto-generated method stub
//super.init();
//生成测试用的数据
datas = new ArrayList<String>();
for(int i=1;i<105;i++){
String str;
str="String"+i;
datas.add(str);
}
}
}
pager.tdl
<pre name="code" class="html"><?xml version="1.0" encoding="UTF-8"?> <taglib> <tlib-version>0.0</tlib-version> <jsp-version>0.0</jsp-version> <short-name>q</short-name> <!--统一资源定位符，唯一即可--> <uri>http://www.csdn.net/cjc/tags/pagertag</uri> <!-- 自定义标签的描述信息 --> <tag> <!-- 标签名 --> <name>pager</name> <!-- 对应的标签处理类全限定名 --> <tag-class>mytags.PagerTag</tag-class> <!-- 标签主体的类型 --> <body-content>empty</body-content> <!-- 当前页号属性的描述信息 --> <attribute> <!-- 属性名 --> <name>pageNo</name> <!-- 该属性是否为必要的 --> <required>true</required> <!-- 属性值是否可以在JSP运行时期动态产生 --> <rtexprvalue>true</rtexprvalue> <!-- 属性的数据类型 --> <type>int</type> </attribute> <!-- 总记录数属性的描述信息 --> <attribute> <name>recordCount</name> <required>true</required> <rtexprvalue>true</rtexprvalue> <type>int</type> </attribute> <!-- 总页数属性的描述信息 --> <attribute> <name>pageSize</name> <required>true</required> <rtexprvalue>true</rtexprvalue> <type>int</type> </attribute> <!-- 分页标签要跳转的URI属性的描述信息 --> <attribute> <name>url</name> <required>true</required> <rtexprvalue>true</rtexprvalue> <type>java.lang.String</type> </attribute> </tag> </taglib>
pager.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1" import ="java.util.*"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@ taglib uri="http://www.csdn.net/cjc/tags/pagertag" prefix="q" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>My Define Pager</title>
<style type="text/css">
.pagination{padding:5px; float:right;}
.pagination a, .pagination a:link, .pagination a:visted
{
padding: 2px 5px 2px 5px;
margin: 2px;
border: 1px solid #aaaadd;
text-decoration: none;
color: #006699;
}
.pagination a:hover, .pagination a:active {
border: 1px solid #ff0000;
color: #000;
text-decoration: none;
}
.pagination span.current {
padding: 2px 5px 2px 5px;
margin: 2px;
border: 1px solid #ff0000;
font-weight: bold;
background-color: #ff0000;
color: #FFF;
}
</style>
</head>
<body>
<table cellspacing="1" cellpadding="5" border="1" width="500" align="center">
<%
out.println("<hr/>");
List<String> datas = (List<String>)request.getAttribute("subdatas");
for(int i=0;i<datas.size();i++){
out.println("<tr><td>");
out.println(datas.get(i));
out.println("</td></tr>");
}
%>
</table>
<!--EL表达式 -->
<q:pager pageNo="${pageNo}"
pageSize="${pageSize}"
recordCount="${recordCount}"
url="TestPagerTagServlet" />
</body>
</html>
index.html
<!DOCTYPE html> <html> <head> <meta charset="UTF-8"> <title>Insert title here</title> </head> <body> <a href="TestPagerTagServlet">Test it now</a> </body> </html>
4、结果
时间： 2024-10-07 05:31:02