package com.hoo.ehcache.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;
/**
* <b>function:</b> mobile 頁面緩存過濾器
* @author hoojo
* @createDate 2012-7-4 上午09:34:30
* @file PageEhCacheFilter.java
* @package com.hoo.ehcache.filter
* @project Ehcache
* @blog http://blog.csdn.net/IBM_hoojo
* @email hoojo_@126.com
* @version 1.0
*/
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;
}
}
}
// 如果包含我們要緩存的url 就緩存該頁面，否則執(zhí)行正常的頁面轉(zhuǎn)向
if (flag) { String query = request.getQueryString();
if (query != null) { query = "?" + query;
}
log.info("當(dāng)前請求被緩存：" + 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壓縮
* @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;
}
}