added check for negative input in ObjectProducer

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 #FindBugs User Preferences
-#Tue Apr 21 14:17:42 CEST 2015
+#Tue Apr 21 16:50:39 CEST 2015
 detector_threshold=3
 effort=max
 excludefilter0=.fbExcludeFilterFile|true

src/main/java/teetime/stage/ObjectProducer.java

@@ -32,6 +32,9 @@ public final class ObjectProducer<T> extends AbstractProducerStage<T> {
 	 * @since 1.0
 	 */
 	public ObjectProducer(final long numInputObjects, final ConstructorClosure<T> inputObjectCreator) {
+		if (numInputObjects < 0) {
+			throw new IllegalArgumentException("numInputObjects must be non-negative.");
+		}
 		this.numInputObjects = numInputObjects;
 		this.inputObjectCreator = inputObjectCreator;
 	}

wiki @ 0e447457

-Subproject commit 162510ff4d2f04011498ba6920aae0c78347c6c8
+Subproject commit 0e4474577e1f49bc96e734c286b2d9e0363895e8

src/test/java/teetime/stage/ObjectProducerTest.java

@@ -53,6 +53,14 @@ public class ObjectProducerTest {
 		assertThat(results, is(empty()));
 	}
 
+	@Test(expected = IllegalArgumentException.class)
+	public void producerShouldFailOnNegativeInput() {
+		final List<Integer> results = new ArrayList<Integer>();
+		final ObjectProducer<Integer> producer = new ObjectProducer<Integer>(-1, new Generator());
+
+		test(producer).and().receive(results).from(producer.getOutputPort()).start();
+	}
+
 	private static class Generator implements ConstructorClosure<Integer> {
 
 		private int counter = 1;