/*******************************************************************************
* Copyright (c) MOBAC developers
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
******************************************************************************/
package mobac.tools.testtileserver.servlets;
import java.io.IOException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.log4j.Logger;
public abstract class AbstractTileServlet extends HttpServlet {
protected static final SecureRandom RND = new SecureRandom();
protected final Logger log;
/**
* Error rate in percent [0..100]
*/
protected int errorRate = 0;
protected boolean errorOnUrl = true;
protected int delay = 0;
private final MessageDigest md5;
public AbstractTileServlet() {
log = Logger.getLogger(this.getClass());
try {
md5 = MessageDigest.getInstance("MD5");
} catch (NoSuchAlgorithmException e) {
throw new RuntimeException(e);
}
}
@Override
protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException,
IOException {
try {
Thread.sleep(delay);
} catch (InterruptedException e) {
}
if (errorResponse(request, response))
return;
super.service(request, response);
}
public boolean errorResponse(HttpServletRequest request, HttpServletResponse response) throws IOException {
if (errorRate == 0)
return false;
if (errorOnUrl) {
String url = request.getRequestURL() + request.getQueryString();
byte[] digest = md5.digest(url.getBytes());
int hash = Math.abs(digest[4] % 100);
log.debug(url.toString() + " -> " + hash + ">" + errorRate + "?");
if (hash > errorRate)
return false;
} else {
int rnd = RND.nextInt(100);
if (rnd > errorRate)
return false;
}
response.sendError(404);
log.debug("Error response sent");
return true;
}
public int getErrorRate() {
return errorRate;
}
public void setErrorRate(int errorRate) {
this.errorRate = errorRate;
}
public boolean isErrorOnUrl() {
return errorOnUrl;
}
public void setErrorOnUrl(boolean errorOnUrl) {
this.errorOnUrl = errorOnUrl;
}
public int getDelay() {
return delay;
}
public void setDelay(int delay) {
this.delay = delay;
}
}