jsp 自定义分页标签

花了一上午简单研究了下自定义标签。就弄了个自定义的分页标签。代码没有怎么仔细优化。先贴上来，：）

1,标签的实现类NumenTag.java

转自http://blog.youkuaiyun.com/numen_wlm/archive/2007/01/30/1497778.aspx

 

import  java.util.ArrayList;
import  java.util.HashMap;
import  java.util.List;
import  java.util.Map;

import  javax.servlet.jsp.JspException;
import  javax.servlet.jsp.JspWriter;
import  javax.servlet.jsp.tagext.TagSupport;

/** */ /**
 * 自定义的分页标签
 * 
 * @author 马万林
 * 
 */
public   class  NumenTag  extends  TagSupport  {

    private String url = null;

    private Result result;

    private String page = null;

    private String[] p;

    private Map kv = new HashMap();

    private List key = null;

    /** *//**
     * 分离参数
     * @param params
     */
    public void setParams(String params) {
        key = new ArrayList();
        p = params.split(";");
        for (int i = 0; p.length>1&&i < p.length; i++) {
            kv.put(p[i].split(":")[0], p[i].split(":")[1]);
            key.add(p[i].split(":")[0]);
        }
    }

    /** *//**
     * 分页的结果
     * @param result
     */
    public void setResult(String result) {
        this.result = (Result) pageContext.getRequest().getAttribute("result");
        this.page = (String) pageContext.getRequest().getAttribute("page");
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public int doStartTag() throws JspException {
        StringBuffer sb = null;
        if (result != null && result.getContent() != null
                && result.getContent().size() > 0) {
            sb = new StringBuffer("分页: ");
            if (result.getPage().getHasPrePage()){
                sb.append("<a href='").append(url);
                if (url.indexOf("?") == -1)
                    sb.append("?page=1");
                else
                    sb.append("&page=1");
                linkParams(sb);
                sb.append("'>").append("首页").append("</a>").append(" | ");
                sb.append("<a href='").append(url);
                if (url.indexOf("?") == -1)
                    sb.append("?page=").append(
                            result.getPage().getPreviousPage());
                else
                    sb.append("&page=").append(
                            result.getPage().getPreviousPage());
                linkParams(sb);
                sb.append("'>").append("上页").append("</a>").append(" | ");
            }
            if (result.getPage().getHasNextPage()) {
                sb.append("<a href='").append(url);
                if (url.indexOf("?") == -1)
                    sb.append("?page=").append(result.getPage().getNextPage());
                else
                    sb.append("&page=").append(result.getPage().getNextPage());
                linkParams(sb);
                sb.append("'>").append("下页").append("</a>").append(" | ");
                sb.append("<a href='").append(url);
                if (url.indexOf("?") == -1)
                    sb.append("?page=").append(result.getPage().getTotalPage());
                else
                    sb.append("&page=").append(result.getPage().getTotalPage());
                linkParams(sb);
                sb.append("'>").append("尾页").append("</a>");
            }
            sb
                    .append(" 跳转到:<select name='goToPage' onchange='javascript:goPage(this.value)'>");
            int s = result.getPage().getTotalCount();
            for (int i = 1; i <= s; i++) {
                sb.append("<option value=").append(i);
                if (Integer.parseInt(page) == i)
                    sb.append(" selected");
                sb.append(">第").append(i).append("页</option>");
            }
            sb.append("</select>");
            sb.append("<script language=javascript>");
            sb.append("function goPage(page){").append("window.location='")
                    .append(url);
            if (url.indexOf("?") == -1)
                sb.append("?page='+").append("page");
            else
                sb.append("&page='+").append("page");
            sb.append("+'");
            linkParams(sb);
            sb.append("';");
            sb.append("}");
            sb.append("</script>");
        }
        try {
            if (sb != null) {
                JspWriter out = pageContext.getOut();
                out.print(sb);
            }
        } catch (Exception e) {
            throw new JspException(e);
        }
        return EVAL_PAGE;
    }
    
    /** *//**
     * 链接参数处理
     * @param sb
     */
    private void linkParams(StringBuffer sb) {
        for (int i = 0; i < key.size(); i++) {
            sb.append("&").append(key.get(i)).append("=").append(
                    kv.get(key.get(i)));
        }
    }

}

 

2,标签定义文件numentag.tld

 

<? xml  version="1.0"  encoding="utf-8"   ?>
  <! DOCTYPE taglib PUBLIC "-//Sun Microsystems, Inc.//DTD JSP Tag Library 1.2//EN" "http://java.sun.com/dtd/web-jsptaglibrary_1_2.dtd" >
< taglib >
     < tlib-version > 1.0 </ tlib-version >
     < jsp-version > 1.2 </ jsp-version >
     < short-name > numen </ short-name >
     <!-- OutputTag -->
     < tag >
         < name > out </ name >
         < tag-class > cn.cityyouth.util.NumenTag </ tag-class >
         < body-content > empty </ body-content >
         < attribute >
             < name > url </ name >
             < required > true </ required >
             < rtexprvalue > true </ rtexprvalue >
         </ attribute >
         < attribute >
             < name > result </ name >
             < required > true </ required >
             < rtexprvalue > true </ rtexprvalue >
         </ attribute >
         < attribute >
             < name > params </ name >
             < required > false </ required >
             < rtexprvalue > true </ rtexprvalue >
         </ attribute >
     </ tag >
</ taglib >

 

3.js

< %@ page  contentType ="text/html; charset=utf-8" % >
< %@ include  file ="/common/taglibs.jsp" % >
< %@ taglib   uri ="/WEB-INF/numentag.tld"   prefix ="n" % >
< html >
< head >
</ head >
< body >
< table >
< tr >< td >
< n:out  url ="test.do"  result ="result"  params ="${type}" />
</ td ></ tr >
</ table >
</ body >
</ html >