added non-negative restriction

jsprit-core/src/main/java/jsprit/core/problem/job/Service.java

@@ -160,8 +160,10 @@ public class Service implements Job {
 		 * @param dimensionIndex
 		 * @param dimensionValue
 		 * @return the builder
+		 * @throws IllegalArgumentException if dimensionValue < 0
 		 */
 		public Builder addCapacityDimension(int dimensionIndex, int dimensionValue){
+			if(dimensionValue<0) throw new IllegalArgumentException("capacity value cannot be negative");
 			capacityBuilder.addDimension(dimensionIndex, dimensionValue);
 			return this;
 		}

jsprit-core/src/main/java/jsprit/core/problem/job/Shipment.java

@@ -212,9 +212,11 @@ public class Shipment implements Job{
 		 * 
 		 * @param dimIndex
 		 * @param dimVal
-		 * @return
+		 * @return builder
+		 * @throws IllegalArgumentException if dimVal < 0
 		 */
 		public Builder addCapacityDimension(int dimIndex, int dimVal) {
+			if(dimVal<0) throw new IllegalArgumentException("capacity value cannot be negative");
 			capacityBuilder.addDimension(dimIndex, dimVal);
 			return this;
 		}

jsprit-core/src/main/java/jsprit/core/problem/vehicle/VehicleTypeImpl.java

@@ -193,8 +193,10 @@ public class VehicleTypeImpl implements VehicleType {
 		 * @param dimIndex
 		 * @param dimVal
 		 * @return the builder
+		 * @throws IllegalArgumentException if dimVal < 0
 		 */
 		public Builder addCapacityDimension(int dimIndex, int dimVal) {
+			if(dimVal<0) throw new IllegalArgumentException("capacity value cannot be negative");
 			capacityBuilder.addDimension(dimIndex,dimVal);
 			return this;
 		}

jsprit-core/src/test/java/jsprit/core/problem/job/ServiceTest.java

@@ -60,7 +60,7 @@ public class ServiceTest {
 		assertTrue(serviceSet.isEmpty());
 	}
 	
-	@Test(expected=IllegalStateException.class)
+	@Test(expected=IllegalArgumentException.class)
 	public void whenCapacityDimValueIsNegative_throwIllegalStateExpception(){
 		@SuppressWarnings("unused")
 		Service s = Service.Builder.newInstance("s").setLocationId("foo").addCapacityDimension(0, -10).build();

jsprit-core/src/test/java/jsprit/core/problem/job/ShipmentTest.java

@@ -44,6 +44,12 @@ public class ShipmentTest {
 		Shipment one = Shipment.Builder.newInstance("s", -10).setPickupLocation("foo").setDeliveryLocation("foofoo").build();
 	}
 	
+	@Test(expected=IllegalArgumentException.class)
+	public void whenShipmentIsBuiltWithNegativeDemand_itShouldThrowException_v2(){
+		@SuppressWarnings("unused")
+		Shipment one = Shipment.Builder.newInstance("s").addCapacityDimension(0, -10).setPickupLocation("foo").setDeliveryLocation("foofoo").build();
+	}
+	
 	@Test(expected=IllegalArgumentException.class)
 	public void whenIdIsNull_itShouldThrowException(){
 		@SuppressWarnings("unused")

jsprit-core/src/test/java/jsprit/core/problem/vehicle/VehicleTypeImplTest.java

@@ -7,7 +7,7 @@ import org.junit.Test;
 public class VehicleTypeImplTest {
 	
 
-	@Test(expected=IllegalStateException.class)
+	@Test(expected=IllegalArgumentException.class)
 	public void whenTypeHasNegativeCapacityVal_throwIllegalStateExpception(){
 		@SuppressWarnings("unused")
 		VehicleTypeImpl type = VehicleTypeImpl.Builder.newInstance("t").addCapacityDimension(0,-10).build();