/*
* cron4j - A pure Java cron-like scheduler
*
* Copyright (C) 2007-2010 Carlo Pelliccia (www.sauronsoftware.it)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version
* 2.1, as published by the Free Software Foundation.
*
* 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 Lesser General Public License 2.1 for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License version 2.1 along with this program.
* If not, see <http://www.gnu.org/licenses/>.
*/
package example;
import it.sauronsoftware.cron4j.Scheduler;
import it.sauronsoftware.cron4j.TaskExecutor;
import java.io.IOException;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* This servlet enables the user to view and control any ongoing task execution.
* The HTML layout is generated calling the /WEB-INF/ongoing.jsp page.
*/
public class ExecutionServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
// Retrieves the servlet context.
ServletContext context = getServletContext();
// Retrieves the scheduler.
Scheduler scheduler = (Scheduler) context
.getAttribute(Constants.SCHEDULER);
// Retrieves the executors.
TaskExecutor[] executors = scheduler.getExecutingTasks();
// Registers the executors in the request.
req.setAttribute("executors", executors);
// Action requested?
String action = req.getParameter("action");
if ("pause".equals(action)) {
String id = req.getParameter("id");
TaskExecutor executor = find(executors, id);
if (executor != null && executor.isAlive() && !executor.isStopped()
&& executor.canBePaused() && !executor.isPaused()) {
executor.pause();
}
} else if ("resume".equals(action)) {
String id = req.getParameter("id");
TaskExecutor executor = find(executors, id);
if (executor != null && executor.isAlive() && !executor.isStopped()
&& executor.canBePaused() && executor.isPaused()) {
executor.resume();
}
} else if ("stop".equals(action)) {
String id = req.getParameter("id");
TaskExecutor executor = find(executors, id);
if (executor != null && executor.isAlive()
&& executor.canBeStopped() && !executor.isStopped()) {
executor.stop();
}
}
// Layout.
String page = "/WEB-INF/ongoing.jsp";
RequestDispatcher dispatcher = req.getRequestDispatcher(page);
dispatcher.include(req, resp);
}
private TaskExecutor find(TaskExecutor[] executors, String id) {
if (id == null) {
return null;
}
for (int i = 0; i < executors.length; i++) {
String aux = executors[i].getGuid();
if (aux.equals(id)) {
return executors[i];
}
}
return null;
}
}