/*
* Copyright 2012 JBoss Inc
*
* Licensed 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.
*/
package org.optaplanner.webexamples.cloudbalancing;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import javax.servlet.http.HttpSession;
import org.optaplanner.core.api.solver.SolverFactory;
import org.optaplanner.core.api.solver.Solver;
import org.optaplanner.core.api.solver.event.BestSolutionChangedEvent;
import org.optaplanner.core.api.solver.event.SolverEventListener;
import org.optaplanner.examples.cloudbalancing.domain.CloudBalance;
import org.optaplanner.examples.cloudbalancing.persistence.CloudBalancingGenerator;
public class CloudBalancingWebAction {
private static ExecutorService solvingExecutor = Executors.newFixedThreadPool(4);
public void setup(HttpSession session) {
terminateEarly(session);
SolverFactory solverFactory = SolverFactory.createFromXmlResource(
"org/optaplanner/examples/cloudbalancing/solver/cloudBalancingSolverConfig.xml");
Solver solver = solverFactory.buildSolver();
session.setAttribute(CloudBalancingSessionAttributeName.SOLVER, solver);
// Load a problem with 40 computers and 120 processes
CloudBalance unsolvedSolution = new CloudBalancingGenerator(true).createCloudBalance(100, 300);
session.setAttribute(CloudBalancingSessionAttributeName.SHOWN_SOLUTION, unsolvedSolution);
}
public void solve(final HttpSession session) {
final Solver solver = (Solver) session.getAttribute(CloudBalancingSessionAttributeName.SOLVER);
final CloudBalance unsolvedSolution = (CloudBalance) session.getAttribute(CloudBalancingSessionAttributeName.SHOWN_SOLUTION);
solver.addEventListener(new SolverEventListener<CloudBalance>() {
public void bestSolutionChanged(BestSolutionChangedEvent<CloudBalance> event) {
CloudBalance bestSolution = event.getNewBestSolution();
session.setAttribute(CloudBalancingSessionAttributeName.SHOWN_SOLUTION, bestSolution);
}
});
solvingExecutor.submit(new Runnable() {
public void run() {
solver.solve(unsolvedSolution);
}
});
}
public void terminateEarly(HttpSession session) {
final Solver solver = (Solver) session.getAttribute(CloudBalancingSessionAttributeName.SOLVER);
if (solver != null) {
solver.terminateEarly();
session.setAttribute(CloudBalancingSessionAttributeName.SOLVER, null);
}
}
}