package cn.javass.common.web.filter;

import java.util.Enumeration;
import javax.servlet.FilterChain;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import net.sf.ehcache.CacheException;
import net.sf.ehcache.constructs.blocking.LockTimeoutException;
import net.sf.ehcache.constructs.web.AlreadyCommittedException;
import net.sf.ehcache.constructs.web.AlreadyGzippedException;
import net.sf.ehcache.constructs.web.filter.FilterNonReentrantException;
import net.sf.ehcache.constructs.web.filter.SimplePageCachingFilter;
import org.apache.commons.lang.StringUtils;
import org.apache.log4j.Logger;

public class PageEhCacheFilter extends SimplePageCachingFilter {

    private final static Logger log = Logger.getLogger(PageEhCacheFilter.class);
    private final static String FILTER_URL_PATTERNS = "patterns";
    private static String[] cacheURLs;
    private void init() throws CacheException {
        String patterns = filterConfig.getInitParameter(FILTER_URL_PATTERNS);
        cacheURLs = StringUtils.split(patterns, ",");
    }

    @Override
    protected void doFilter(final HttpServletRequest request,
    final HttpServletResponse response, final FilterChain chain)
    throws AlreadyGzippedException, AlreadyCommittedException,
    FilterNonReentrantException, LockTimeoutException, Exception {
        if (cacheURLs == null) {
            init();
        }
        String url = request.getRequestURI();
        boolean flag = false;
        if (cacheURLs != null && cacheURLs.length > 0) {
            for (String cacheURL : cacheURLs) {
                if (url.contains(cacheURL.trim())) {
                    flag = true;
                    break;
                }
            }
        }

        // 如果包含我们要缓存的url 就缓存该页面，否则执行正常的页面转向

        if (flag) {
            String query = request.getQueryString();
            if (query != null) {
                query = "?" + query;
            }
            log.info("当前请求被缓存：" + url + query);
            super.doFilter(request, response, chain);
        } else {
            chain.doFilter(request, response);
        }
    }

    @SuppressWarnings("unchecked")
    private boolean headerContains(final HttpServletRequest request,
            final String header, final String value) {
        logRequestHeaders(request);
        final Enumeration accepted = request.getHeaders(header);
        while (accepted.hasMoreElements()) {
            final String headerValue = (String) accepted.nextElement();
            if (headerValue.indexOf(value) != -1) {
                return true;
            }
        }
        return false;
    }

    /**
     * 
     * @see net.sf.ehcache.constructs.web.filter.Filter#acceptsGzipEncoding(javax.servlet.http.HttpServletRequest)
     * 
     *      <b>function:</b> 兼容ie6/7 gzip压缩
     * 
     * @author hoojo
     * 
     * @createDate 2012-7-4 上午11:07:11
     */

    @Override
    protected boolean acceptsGzipEncoding(HttpServletRequest request) {
        boolean ie6 = headerContains(request, "User-Agent", "MSIE 6.0");
        boolean ie7 = headerContains(request, "User-Agent", "MSIE 7.0");
        return acceptsEncoding(request, "gzip") || ie6 || ie7;

    }

}

2.3 web.xml

            <!-- 缓存、使用页面缓存,gzip压缩核心过滤器 -->
            <filter>
                <filter-name>PageEhCacheFilter</filter-name>
                <filter-class>cn.javass.common.web.filter.PageEhCacheFilter</filter-class>
                <init-param>
                    <param-name>patterns</param-name>
                    <!-- 配置你需要缓存的url -->
                    <param-value>/pageCache.jsp,/pageCache </param-value>
                </init-param>
            </filter>
            <filter-mapping>
                <filter-name>PageEhCacheFilter</filter-name>
                <url-pattern>/pageCache</url-pattern>
            </filter-mapping>

2.4测试

package cn.javass.demo.web.controller;

import javax.servlet.http.HttpServletRequest;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;


/**
 * @author Zhangkaitao
 * @version 1.0
 */
@Controller
public class pageCacheController {
    
    @RequestMapping(value = "/pageCache")
    public String index(HttpServletRequest request){
        return "pageCache";
    }

}

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@page import="java.util.Date"%>
<%@ include file="inc/header.jsp"%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>欢迎</title>
</head>
<body>
<p>使用new Date()来检测该页面是否被缓存</p>
<%=new Date()%>
</body>
</html>

访问两次该页面，检测时间没有发生变化，说明该url被缓存了

八、xss过滤器

使用XssRequestWrapper装饰器模式

页面缓存可参考：http://www.cnblogs.com/crazylqy/p/4325363.html

其他部分请直接看源码

优质内容筛选与推荐>>
1、UVa1583 Digit Generator
2、用例建模Use Case Modeling
3、javaFX制作helloWorld的几种方式
4、Java读取oracle数据库中blob字段数据文件保存到本地文件(转载)
5、POJ 3126-Prime Path(BFS)

赞赏

长按二维码向我转账

受苹果公司新规定影响，微信 iOS 版的赞赏功能被关闭，可通过二维码转账支持公众号。

阅读

好看

已推荐到看一看

你的朋友可以在“发现”-“看一看”看到你认为好看的文章。

取消 推荐

我知道了

已取消，“好看”想法已同步删除

知道了

已推荐到看一看 和朋友分享想法

最多200字，当前共字 发送

已发送

朋友将在看一看看到

确定

分享你的想法...

取消

分享想法到看一看

确定

最多200字，当前共字

发送中

网络异常，请稍后重试

知道了