DoubleClickController.java :  » Portal » liferay-portal-4.4.2 » com » liferay » filters » doubleclick » Java Open Source

/**
 * Copyright (c) 2000-2008 Liferay, Inc. All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package com.liferay.filters.doubleclick;

import com.liferay.util.servlet.filters.CacheResponse;
import com.liferay.util.servlet.filters.CacheResponseData;
import com.liferay.util.servlet.filters.CacheResponseUtil;

import java.io.IOException;
import java.io.Serializable;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * <a href="DoubleClickController.java.html"><b><i>View Source</i></b></a>
 *
 * @author Olaf Fricke
 * @author Brian Wing Shun Chan
 *
 */
public class DoubleClickController implements Serializable {

  public void control(
      HttpServletRequest req, HttpServletResponse res, FilterChain chain)
    throws IOException, ServletException {

    boolean firstRequest = false;

    CacheResponse cacheResponse = null;

    synchronized (this) {
      if (_cacheResponse == null) {
        firstRequest = true;

        _cacheResponse = new CacheResponse(
          res, DoubleClickFilter.ENCODING);
        _throwable = null;
      }

      cacheResponse = _cacheResponse;
    }

    if (firstRequest) {
      try {
        chain.doFilter(req, _cacheResponse);
      }
      catch (Throwable t) {
        _throwable = t;
      }
      finally {
        synchronized (this) {
          _cacheResponse = null;

          notifyAll();
        }
      }
    }
    else {
      synchronized (this) {
        while (_cacheResponse != null) {
          try {
            wait();
          }
          catch (InterruptedException ie) {
            Thread.currentThread().interrupt();
          }
        }
      }
    }

    if (_throwable != null) {
      try {
        throw _throwable;
      }
      catch (IOException ioe) {
        throw ioe;
      }
      catch (ServletException se) {
        throw se;
      }
      catch (RuntimeException re) {
        throw re;
      }
      catch (Error e) {
        throw e;
      }
      catch (Throwable t) {
        throw new RuntimeException(t);
      }
    }

    CacheResponseData data = new CacheResponseData(
      cacheResponse.getData(), cacheResponse.getContentType(),
      cacheResponse.getHeaders());

    CacheResponseUtil.write(res, data);
  }

    private CacheResponse _cacheResponse;
    private Throwable _throwable;

}