src/main/java/net/berack/upo/valpre/SimulationBuilder.java

@@ -2,6 +2,7 @@ package net.berack.upo.valpre;
 
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.io.PrintStream;
 import java.util.concurrent.ExecutionException;
 import com.esotericsoftware.kryo.KryoException;
 
@@ -13,6 +14,7 @@ import net.berack.upo.valpre.sim.EndCriteria.MaxTime;
 import net.berack.upo.valpre.sim.Net;
 import net.berack.upo.valpre.sim.SimulationMultiple;
 import net.berack.upo.valpre.sim.stats.CsvResult;
+import net.berack.upo.valpre.sim.stats.Result;
 
 /**
  * This class is responsible for running the simulation. It parses the arguments
@@ -230,23 +232,38 @@ public class SimulationBuilder {
      * @throws ExecutionException   If the simulation has an error.
      * @throws IOException          If the CSV file has a problem.
      */
-    public void run() throws InterruptedException, ExecutionException, IOException {
+    public Result.Summary run() throws InterruptedException, ExecutionException, IOException {
+        return this.run(System.out);
+    }
+
+    /**
+     * Run the simulation with the given parameters.
+     * At the end it prints the results and saves them to a CSV file if requested.
+     * 
+     * @param out the output stream to print the results
+     * @throws InterruptedException If the simulation is interrupted.
+     * @throws ExecutionException   If the simulation has an error.
+     * @throws IOException          If the CSV file has a problem.
+     */
+    public Result.Summary run(PrintStream out) throws InterruptedException, ExecutionException, IOException {
         var nano = System.nanoTime();
         var sim = new SimulationMultiple(this.net);
         var summary = switch (this.type) {
-            case Incremental -> sim.runIncremental(this.seed, this.runs, this.confidences, this.endCriteria);
+            case Incremental -> sim.runIncremental(this.seed, this.runs, out, this.confidences, this.endCriteria);
             case Parallel -> sim.runParallel(this.seed, this.runs, this.endCriteria);
             case Normal -> sim.run(this.seed, this.runs, this.endCriteria);
         };
         nano = System.nanoTime() - nano;
 
-        System.out.print(summary);
+        out.print(summary);
-        System.out.println("Final time " + nano / 1e6 + "ms");
+        out.println("Final time " + nano / 1e6 + "ms");
 
         if (csv != null) {
             new CsvResult(this.csv).saveResults(summary.getRuns());
-            System.out.println("Data saved to " + this.csv);
+            out.println("Data saved to " + this.csv);
         }
+
+        return summary;
     }
 
     /**

src/main/java/net/berack/upo/valpre/sim/SimulationMultiple.java

@@ -1,5 +1,6 @@
 package net.berack.upo.valpre.sim;
 
+import java.io.PrintStream;
 import java.util.ArrayList;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Executors;
@@ -99,16 +100,21 @@ public class SimulationMultiple {
      * Run the simulation multiple times with the given seed and end criteria. The
      * simulation runs will stop when the relative error of the confidence index is
      * less than the given value.
-     * The results are printed on the console.
+     * The results are printed on the PrintStream.
      * 
      * @param seed        The seed to use for the random number generator.
+     * @param runs        The maximum number of runs to perform.
+     * @param stream      The PrintStream to print the results.
+     * @param confidences The confidence indices to use to determine when to stop
+     *                    the simulation.
      * @param criterias   The criteria to determine when to end the simulation. If
      *                    null then the simulation will run until there are no more
      *                    events.
      * @return The statistics the network.
      * @throws IllegalArgumentException If the confidence is not set.
      */
-    public Result.Summary runIncremental(long seed, int runs, ConfidenceIndices confidences, EndCriteria... criterias) {
+    public Result.Summary runIncremental(long seed, int runs, PrintStream stream, ConfidenceIndices confidences,
+            EndCriteria... criterias) {
         if (confidences == null)
             throw new IllegalArgumentException("Confidence must be not null");
 
@@ -133,11 +139,11 @@ public class SimulationMultiple {
                 var oneSting = String.join("], [", errString);
 
                 output.append('[').append(oneSting).append("]");
-                System.out.print(output);
+                stream.print(output);
             }
         }
 
-        System.out.println(); // remove last printed line
+        stream.println(); // remove last printed line
         return results;
     }
 

src/test/java/net/berack/upo/valpre/sim/TestSaveExamplesNet.java

@@ -4,6 +4,8 @@ import static org.junit.Assert.assertArrayEquals;
 import static org.junit.Assert.assertEquals;
 
 import java.io.IOException;
+import java.io.OutputStream;
+import java.io.PrintStream;
 import java.util.HashSet;
 import org.junit.Test;
 import org.junit.jupiter.api.AfterAll;
@@ -153,33 +155,39 @@ public class TestSaveExamplesNet {
     @Test
     @AfterAll
     public void multiSimulation1() throws Exception {
+        try (var newOut = new PrintStream(OutputStream.nullOutputStream())) {
             new SimulationBuilder(net1)
                     .setCsv(csv1)
                     .setMaxRuns(1000)
                     .setSeed(2007539552L)
                     .setParallel(true)
-                .run();
+                    .run(newOut);
+        }
     }
 
     @Test
     @AfterAll
     public void multiSimulation2() throws Exception {
+        try (var newOut = new PrintStream(OutputStream.nullOutputStream())) {
             new SimulationBuilder(net2)
                     .setCsv(csv2)
                     .setMaxRuns(1000)
                     .setSeed(2007539552L)
                     .setParallel(true)
-                .run();
+                    .run(newOut);
+        }
     }
 
     @Test
     @AfterAll
     public void multiSimulation3() throws Exception {
+        try (var newOut = new PrintStream(OutputStream.nullOutputStream())) {
             new SimulationBuilder(net3)
                     .setCsv(csv3)
                     .setMaxRuns(1000)
                     .setSeed(2007539552L)
                     .setParallel(true)
-                .run();
+                    .run(newOut);
+        }
     }
 }