泛域名解析

web.xml配置

<!-- webSite dns 泛域名解析 -->
	 <filter>
		<filter-name>webDnsFilter</filter-name>
		<filter-class>
		net.hlj.schoolWebsite.Filter.WebDnsFilter
		</filter-class>
		<init-param>
			<param-name>error</param-name>
			<param-value>/error.jsp</param-value>
		</init-param>
		<init-param>
			<param-name>ignorePages</param-name>
			<param-value>
				/error.jsp,/include/ajax_action.jsp,/download
			</param-value>
		</init-param>
		<init-param>
			<param-name>ignoreExtensions</param-name>
			<param-value>
				jpeg,gif,css,jpg,js,htm,html,swf,png
			</param-value>
		</init-param>
	 </filter>
	 <filter-mapping>
		<filter-name>webDnsFilter</filter-name>
		<url-pattern>/*</url-pattern>
	</filter-mapping>
	<!-- webSite dns -->

实现类：

package net.hlj.schoolWebsite.Filter;

import java.io.IOException;
import java.util.Vector;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import net.hlj.util.*;
/**
 * 备注：对网站域名做泛解析
 * @author:未知
 * @date:2012-01-30
 */
public class WebDnsFilter implements Filter {
	Vector<String> nonfilter = new Vector<String>();

	private static String contextPath = null;

	private static boolean hasContextPath = false;

	private String forwardPage;

	/*
	 * (non-Javadoc)
	 * 
	 * @see javax.servlet.Filter#init(javax.servlet.FilterConfig)
	 */
	public void init(FilterConfig config) throws ServletException {
		forwardPage = config.getInitParameter("error");
		String[] notFilter = config.getInitParameter("ignorePages").split(",");
		for (int i = 0; i < notFilter.length; i++) {
			nonfilter.add(notFilter[i]);
		}
		String[] notFilterExt = config.getInitParameter("ignoreExtensions").split(",");
		for (int i = 0; i < notFilterExt.length; i++) {
			nonfilter.add(notFilterExt[i]);
		}
		nonfilter.add(forwardPage);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see javax.servlet.Filter#doFilter(javax.servlet.ServletRequest,
	 *      javax.servlet.ServletResponse, javax.servlet.FilterChain)
	 */
	public void doFilter(ServletRequest srequest, ServletResponse sresponse,
			FilterChain chain) throws IOException, ServletException {

		HttpServletRequest request = (HttpServletRequest) srequest;
	 
		String uri = request.getRequestURI();
		//System.out.println(uri);
		String dns = "";
		String forwordPage="";
		//String pageName="";
		String ext="";
		String basePath = request.getServerName();
		if (basePath != null) {
			dns = basePath.substring(0, basePath.indexOf("."));
		}
		if (hasContextPath(request))
			uri = uri.substring(uri.indexOf("/", 1));
			//System.out.println(uri);
			ext=uri.substring(uri.lastIndexOf(".")+1);
			//pageName=uri.substring(uri.lastIndexOf(".")+1);
		if (infiltermap(uri)&&infiltermap(ext)) {
			if (dns != null && !dns.equals("www")&&!UtilTool.ipvalid(basePath)) {//ip留测试用
//				if(uri.equals("/showNews.jsp"))
//				{
//					forwordPage="/schoolWebsite/webSite/showNews.jsp";
//				}
//				else if(uri.equals("/showInfo.jsp"))
//				{
//					forwordPage="/schoolWebsite/webSite/showInfo.jsp";
//				}
//				else
//				{
//					forwordPage="/schoolWebsite/webSite/index.jsp";
//				}
				
				RequestDispatcher rd = request
						.getRequestDispatcher(forwordPage);
				rd.forward(srequest, sresponse);
				return;
			}
		}
		chain.doFilter(srequest, sresponse);
	}

	public boolean hasContextPath(HttpServletRequest request) {
		if (contextPath == null) {
			contextPath = request.getContextPath();
			hasContextPath = contextPath.length() > 0;
		}
		return hasContextPath;
	}

	private boolean infiltermap(String uri) {
		return !nonfilter.contains(uri);
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see javax.servlet.Filter#destroy()
	 */
	public void destroy() {

	}
}