package org.apache.jcs.auxiliary.remote.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.OutputStream;
  import java.net.UnknownHostException;
  import java.rmi.RemoteException;
  import java.rmi.registry.LocateRegistry;
  import java.util.Properties;
  
  import javax.servlet.ServletException;
  import javax.servlet.http.HttpServlet;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.HttpServletResponse;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.jcs.access.exception.CacheException;
  import org.apache.jcs.engine.control.CompositeCacheManager;
  import org.apache.jcs.utils.net.HostNameUtil;
  import org.apache.jcs.utils.props.PropertyLoader;
  
  /**
   * This servlet can be used to startup the JCS remote cache. It is easy to deploy the remote server
   * in a tomcat base. This give you an easy way to monitor its activity.
   * <p>
   * <code>
   *  <servlet>
          <servlet-name>JCSRemoteCacheStartupServlet</servlet-name>
          <servlet-class>
               org.apache.jcs.auxiliary.remote.server.RemoteCacheStartupServlet
          </servlet-class>
          <load-on-startup>1</load-on-startup>
      </servlet>
  
  
      <servlet-mapping>
          <servlet-name>JCSRemoteCacheStartupServlet</servlet-name>
          <url-pattern>/jcs</url-pattern>
      </servlet-mapping>
   * </code>
   * @author Aaron Smuts
   */
  public class RemoteCacheStartupServlet
      extends HttpServlet
  {
      /** Don't change */
      private static final long serialVersionUID = 1L;
  
      /** The logger */
      private final static Log log = LogFactory.getLog( RemoteCacheStartupServlet.class );
  
      /** The default port to start the registry on.  */
      private static final int DEFAULT_REGISTRY_PORT = 1101;
  
      /** properties file name */
      private static final String DEFAULT_PROPS_FILE_NAME = "cache";
  
      /** properties file Suffix */
      private static final String DEFAULT_PROPS_FILE_SUFFIX = "ccf";
  
      /** properties file name, must set prior to calling get instance */
      private final String propsFileName = DEFAULT_PROPS_FILE_NAME;
  
      /** properties file name, must set prior to calling get instance */
      private final String fullPropsFileName = DEFAULT_PROPS_FILE_NAME + "." + DEFAULT_PROPS_FILE_SUFFIX;
  
      /**
       * Starts the registry and then tries to bind to it.
       * <p>
       * Gets the port from a props file. Uses the local host name for the registry host. Tries to
       * start the registry, ignoring failure. Starts the server.
       * <p>
       * @throws ServletException
       */
      @Override
      public void init()
          throws ServletException
      {
          super.init();
          // TODO load from props file or get as init param or get from jndi, or
         // all three
         int registryPort = DEFAULT_REGISTRY_PORT;
 
         try
         {
             Properties props = PropertyLoader.loadProperties( propsFileName );
             if ( props != null )
             {
                 String portS = props.getProperty( "registry.port", String.valueOf( DEFAULT_REGISTRY_PORT ) );
 
                 try
                 {
                     registryPort = Integer.parseInt( portS );
                 }
                 catch ( NumberFormatException e )
                 {
                     log.error( "Problem converting port to an int.", e );
                 }
             }
         }
         catch ( Exception e )
         {
             log.error( "Problem loading props.", e );
         }
         catch ( Throwable t )
         {
             log.error( "Problem loading props.", t );
         }
 
         // we will always use the local machine for the registry
         String registryHost;
         try
         {
             registryHost = HostNameUtil.getLocalHostAddress();
 
             if ( log.isDebugEnabled() )
             {
                 log.debug( "registryHost = [" + registryHost + "]" );
             }
 
             if ( "localhost".equals( registryHost ) || "127.0.0.1".equals( registryHost ) )
             {
                 log.warn( "The local address [" + registryHost
                     + "] is INVALID.  Other machines must be able to use the address to reach this server." );
             }
 
             try
             {
                 LocateRegistry.createRegistry( registryPort );
             }
             catch ( RemoteException e )
             {
                 log.error( "Problem creating registry.  It may already be started. " + e.getMessage() );
             }
             catch ( Throwable t )
             {
                 log.error( "Problem creating registry.", t );
             }
 
             try
             {
                 RemoteCacheServerFactory.startup( registryHost, registryPort, "/" + fullPropsFileName );
                 if ( log.isInfoEnabled() )
                 {
                     log.info( "Remote JCS Server started with properties from " + fullPropsFileName );
                 }
             }
             catch ( IOException e )
             {
                 log.error( "Problem starting remote cache server.", e );
             }
 
             catch ( Throwable t )
             {
                 log.error( "Problem starting remote cache server.", t );
             }
         }
         catch ( UnknownHostException e )
         {
             log.error( "Could not get local address to use for the registry!", e );
         }
     }
 
     /**
      * It just dumps the stats.
      * <p>
      * @param request
      * @param response
      * @throws ServletException
      * @throws IOException
      */
     @Override
     protected void service( HttpServletRequest request, HttpServletResponse response )
         throws ServletException, IOException
     {
         String stats = "";
 
         try
         {
             stats = CompositeCacheManager.getInstance().getStats();
         }
         catch (CacheException e)
         {
             throw new ServletException(e);
         }
 
         if ( log.isInfoEnabled() )
         {
             log.info( stats );
         }
 
         try
         {
             OutputStream os = response.getOutputStream();
             os.write( stats.getBytes() );
             os.close();
         }
         catch ( IOException e )
         {
             log.error( "Problem writing response.", e );
         }
     }
 
     /**
      * shuts the cache down.
      */
     @Override
     public void destroy()
     {
         super.destroy();
 
         log.info( "Shutting down remote cache " );
 
         try
         {
             CompositeCacheManager.getInstance().shutDown();
         }
         catch (CacheException e)
         {
             log.error("Could not retrieve cache manager instance", e);
         }
     }
 }