struts2做的分页标签

package com.tangs.tag; import com.opensymphony.xwork2.util.ValueStack; import java.io.IOException; import java.io.Writer; import java.util.logging.Level; import java.util.logging.Logger; import org.apache.struts2.components.Component; /** * 分页逻辑Bean * * @author tangs */ public class Pages extends Component { private String cpage; private String total; private String url; public String getCpage() { return cpage; } public void setCpage(String cpage) { this.cpage = cpage; } public String getTotal() { return total; } public void setTotal(String total) { this.total = total; } public String getUrl() { return url; } public void setUrl(String url) { this.url = url; } public Pages(ValueStack arg0) { super(arg0); } @Override public boolean start(Writer writer) { boolean result = super.start(writer); try { StringBuilder str = new StringBuilder(); boolean isValid = true; // 从ValueStack中取出数值 if (isValid) { if (total.startsWith("%{") && total.endsWith("}")) { total = total.substring(2, total.length() - 1); total = (String) this.getStack().findValue(total); isValid = total == null ? false : true; } else { isValid = false; } } if (isValid) { if (cpage.startsWith("%{") && cpage.endsWith("}")) { cpage = cpage.substring(2, cpage.length() - 1); cpage = (String) this.getStack().findValue(cpage); isValid = cpage == null ? false : true; } else { isValid = false; } } if (isValid) { if (url.startsWith("%{") && url.endsWith("}")) { url = url.substring(2, url.length() - 1); url = (String) this.getStack().findValue(url); isValid = url == null ? false : true; } else { isValid = false; } } if (isValid) { Integer cpageInt = Integer.valueOf(cpage); // 当前页与总页数相等 if (cpage.equals(total)) { // 如果total = 1，则无需分页，显示“[第1页] [共1页]” if ("1".equals(total)) { str.append("[第 " + cpage + " 页]"); str.append(" [共 " + total + " 页]"); } else { // 到达最后一页,显示“[首页] [上一页] [末页]” str.append("<a href='"); str.append(url); str.append("?cpage=1&total=" + total + "&url=" + url); str.append("'>[首页]</a> <a href='"); str.append(url); str.append("?cpage=" + (cpageInt - 1) + "&total=" + total + "&url=" + url); str.append("'>[上一页]</a> <a href='"); str.append(url); str.append("?cpage=" + total + "&total=" + total + "&url=" + url); str.append("'>[末页]</a>"); } } else { // 当前页与总页数不相同 if ("1".equals(cpage)) { // 第一页，显示“[首页] [下一页] [末页]” str.append("<a href='"); str.append(url); str.append("?cpage=1&total=" + total + "&url=" + url); str.append("'>[首页]</a> <a href='"); str.append(url); str.append("?cpage=" + (cpageInt + 1) + "&total=" + total + "&url=" + url); str.append("'>[下一页]</a> <a href='"); str.append(url); str.append("?cpage=" + total + "&total=" + total + "&url=" + url); str.append("'>[末页]</a>"); } else { // 不是第一页，显示“[首页] [上一页] [下一页] [末页]” str.append("<a href='"); str.append(url); str.append("?cpage=1&total=" + total + "&url=" + url); str.append("'>[首页]</a> <a href='"); str.append(url); str.append("?cpage=" + (cpageInt - 1) + "&total=" + total + "&url=" + url); str.append("'>[上一页]</a> <a href='"); str.append(url); str.append("?cpage=" + (cpageInt + 1) + "&total=" + total + "&url=" + url); str.append("'>[下一页]</a> <a href='"); str.append(url); str.append("?cpage=" + total + "&total=" + total + "&url=" + url); str.append("'>[末页]</a>"); } } } writer.write(str.toString()); } catch (IOException ex) { Logger.getLogger(Pages.class.getName()).log(Level.SEVERE, null, ex); } return result; } }