/* Copyright 2009-2016 David Hadka
*
* This file is part of the MOEA Framework.
*
* The MOEA Framework is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or (at your
* option) any later version.
*
* The MOEA Framework 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 for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with the MOEA Framework. If not, see <http://www.gnu.org/licenses/>.
*/
import java.io.File;
import java.io.IOException;
import org.apache.commons.lang3.SystemUtils;
import org.moeaframework.Executor;
import org.moeaframework.core.NondominatedPopulation;
import org.moeaframework.core.Solution;
import org.moeaframework.core.variable.RealVariable;
import org.moeaframework.problem.ExternalProblem;
/**
* Similar to Example4, sockets can be used instead of standard I/O for
* communicating with the external process. Run the command 'make' in the
* ./examples/ folder to compile the executable. This example will only
* work on POSIX (Unix-like) systems.
*/
public class Example6 {
/**
* Notice that the only change is in the constructor, where the hostname and
* port are specified.
*/
public static class MyDTLZ2 extends ExternalProblem {
public MyDTLZ2() throws IOException {
super("localhost", ExternalProblem.DEFAULT_PORT);
}
@Override
public String getName() {
return "DTLZ2";
}
@Override
public int getNumberOfVariables() {
return 11;
}
@Override
public int getNumberOfObjectives() {
return 2;
}
@Override
public int getNumberOfConstraints() {
return 0;
}
@Override
public Solution newSolution() {
Solution solution = new Solution(getNumberOfVariables(),
getNumberOfObjectives());
for (int i = 0; i < getNumberOfVariables(); i++) {
solution.setVariable(i, new RealVariable(0.0, 1.0));
}
return solution;
}
}
public static void main(String[] args) throws IOException,
InterruptedException {
//check if the executable exists
File file = new File("./examples/dtlz2_socket.exe");
if (!file.exists()) {
if (!SystemUtils.IS_OS_UNIX) {
System.err.println("This example only works on POSIX-compliant systems; see the Makefile for details");
return;
}
System.err.println("Please compile the executable by running make in the ./examples/ folder");
return;
}
//run the executable and wait one second for the process to startup
new ProcessBuilder(file.toString()).start();
Thread.sleep(1000);
//configure and run the DTLZ2 function
NondominatedPopulation result = new Executor()
.withProblemClass(MyDTLZ2.class)
.withAlgorithm("NSGAII")
.withMaxEvaluations(10000)
.run();
//display the results
System.out.format("Objective1 Objective2%n");
for (Solution solution : result) {
System.out.format("%.4f %.4f%n",
solution.getObjective(0),
solution.getObjective(1));
}
}
}