org.apache.jcs.auxiliary.lateral.http.server.AbstractDeleteCacheServlet.java Source code

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package org.apache.jcs.auxiliary.lateral.http.server;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import java.io.IOException;
import java.io.PrintWriter;

import java.util.Arrays;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.StringTokenizer;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.SingleThreadModel;

import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.jcs.engine.behavior.ICache;

import org.apache.jcs.engine.control.CompositeCache;
import org.apache.jcs.engine.control.CompositeCacheManager;
import org.apache.jcs.engine.CacheConstants;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.apache.jcs.utils.servlet.BasicHttpAuthenticator;

public abstract class AbstractDeleteCacheServlet extends HttpServlet implements SingleThreadModel {
    private final static Log log = LogFactory.getLog(AbstractDeleteCacheServlet.class);

    /** Description of the Field */
    protected CompositeCacheManager cacheMgr;
    private BasicHttpAuthenticator authenticator;

    /** Description of the Method */
    public void init(ServletConfig config) throws ServletException {
        // subsclass must initialize the cacheMgr before here.
        authenticator = new BasicHttpAuthenticator("jcs");
        super.init(config);
    }

    /** Description of the Method */
    public void service(HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException {
        if (!authenticator.authenticate(req, res)) {
            return;
        }
        Hashtable params = new Hashtable();
        res.setContentType("text/html");
        PrintWriter out = res.getWriter();
        try {
            String paramName;
            String paramValue;

            // GET PARAMETERS INTO HASHTABLE
            for (Enumeration e = req.getParameterNames(); e.hasMoreElements();) {
                paramName = (String) e.nextElement();
                paramValue = req.getParameter(paramName);
                params.put(paramName, paramValue);
                if (log.isDebugEnabled()) {
                    log.debug(paramName + "=" + paramValue);
                }
            }
            String hashtableName = req.getParameter("hashtableName");
            String key = req.getParameter("key");

            if (hashtableName == null) {
                hashtableName = req.getParameter("cacheName");
            }
            out.println("<html><body bgcolor=#FFFFFF>");

            if (hashtableName != null) {

                if (log.isDebugEnabled()) {
                    log.debug("hashtableName = " + hashtableName);
                }
                out.println("(Last hashtableName = " + hashtableName + ")");

                if (hashtableName.equals("ALL")) {

                    // Clear all caches.
                    String[] list = cacheMgr.getCacheNames();
                    Arrays.sort(list);

                    for (int i = 0; i < list.length; i++) {
                        String name = list[i];
                        ICache cache = cacheMgr.getCache(name);
                        cache.removeAll();
                    }
                    out.println("All caches have been cleared!");
                } else {

                    ICache cache = cacheMgr.getCache(hashtableName);

                    String task = (String) params.get("task");
                    if (task == null) {
                        task = "delete";
                    }

                    if (task.equalsIgnoreCase("stats")) {

                        //                        out.println( "<br><br>" );
                        //                        out.println( "<b>Stats for " + hashtableName + ":</b><br>" );
                        //                        out.println( cache.getStats() );
                        //                        out.println( "<br>" );

                    } else {

                        // Remove the specified cache.

                        if (key != null) {
                            if (key.toUpperCase().equals("ALL")) {
                                cache.removeAll();

                                if (log.isDebugEnabled()) {
                                    log.debug("Removed all elements from " + hashtableName);
                                }
                                out.println("key = " + key);
                            } else {
                                if (log.isDebugEnabled()) {
                                    log.debug("key = " + key);
                                }
                                out.println("key = " + key);
                                StringTokenizer toke = new StringTokenizer(key, "_");

                                while (toke.hasMoreElements()) {
                                    String temp = (String) toke.nextElement();
                                    cache.remove(key);

                                    if (log.isDebugEnabled()) {
                                        log.debug("Removed " + temp + " from " + hashtableName);
                                    }
                                }
                            }
                        } else {
                            out.println("key is null");
                        }

                    }
                    // end is task == delete

                }
            } else {
                out.println("(No hashTableName specified.)");
            }

            // PRINT OUT MENU
            out.println("<br>");
            int antiCacheRandom = (int) (10000.0 * Math.random());
            out.println("<a href=?antiCacheRandom=" + antiCacheRandom + ">List all caches</a><br>");
            out.println("<br>");
            out.println("<a href=?hashtableName=ALL&key=ALL&antiCacheRandom=" + antiCacheRandom
                    + "><font color=RED>Clear All Cache Regions</font></a><br>");
            out.println("<br>");
            String[] list = cacheMgr.getCacheNames();
            Arrays.sort(list);
            out.println("<div align=CENTER>");
            out.println("<table border=1 width=80%>");
            out.println("<tr bgcolor=#eeeeee><td>Cache Region Name</td><td>Size</td><td>Status</td><td>Stats</td>");
            for (int i = 0; i < list.length; i++) {
                String name = list[i];
                out.println("<tr><td><a href=?hashtableName=" + name + "&key=ALL&antiCacheRandom=" + antiCacheRandom
                        + ">" + name + "</a></td>");
                ICache cache = cacheMgr.getCache(name);
                out.println("<td>");
                out.print(cache.getSize());
                out.print("</td><td>");
                int status = cache.getStatus();
                out.print(status == CacheConstants.STATUS_ALIVE ? "ALIVE"
                        : status == CacheConstants.STATUS_DISPOSED ? "DISPOSED"
                                : status == CacheConstants.STATUS_ERROR ? "ERROR" : "UNKNOWN");
                out.print("</td>");
                out.println("<td><a href=?task=stats&hashtableName=" + name + "&key=NONE&antiCacheRandom="
                        + antiCacheRandom + ">stats</a></td>");
            }
            out.println("</table>");
            out.println("</div>");
        }
        //CATCH EXCEPTIONS
        catch (Exception e) {
            log.error(e);
            //log.logIt( "hashtableName = " + hashtableName );
            //log.logIt( "key = " + key );
        }
        // end try{
        finally {
            String isRedirect = (String) params.get("isRedirect");
            if (isRedirect == null) {
                isRedirect = "N";
            }
            if (log.isDebugEnabled()) {
                log.debug("isRedirect = " + isRedirect);
            }
            String url;
            if (isRedirect.equals("Y")) {
                url = (String) params.get("url");
                if (log.isDebugEnabled()) {
                    log.debug("url = " + url);
                }
                res.sendRedirect(url);
                // will not work if there's a previously sent header
                out.println("<br>\n");
                out.println(" <script>");
                out.println(" location.href='" + url + "'; ");
                out.println(" </script> ");
                out.flush();
            } else {
                url = "";
            }
            out.println("</body></html>");
        }
    }
    //end service()

}
// end class