Bug fix issue 'No quality data generated'

HydraulicSim manages a  QualitySim data member when Water quality
analysis is needed in order to fill the water quality data in output.

It fixes the issue:
#4

Author: ahuarte47

src/org/addition/epanet/hydraulic/HydraulicSim.java

@@ -33,6 +33,7 @@
 import org.addition.epanet.network.structures.*;
 import org.addition.epanet.network.structures.Link.LinkType;
 import org.addition.epanet.network.structures.Link.StatType;
+import org.addition.epanet.quality.QualitySim;
 import org.addition.epanet.util.ENException;
 import org.addition.epanet.util.Utilities;
 
@@ -151,6 +152,11 @@ private NetSolveStep(int iter, double relerr) {
      */
     protected PipeHeadModel pHLModel;
 
+    /**
+     * Optional related QualitySim when Water quality analysis is needed.
+     */
+    protected QualitySim qualitySim;
+    
     /**
      * Get current hydraulic simulation time.
      *
@@ -183,6 +189,7 @@ public HydraulicSim(Network net, Logger log) throws ENException {
         running = false;
         logger = log;
         createSimulationNetwork(tmpNodes, tmpLinks, net);
+        if (!net.getPropertiesMap().getQualflag().equals(PropertiesMap.QualType.NONE)) qualitySim = new QualitySim(net, log);        
     }
 
     protected void createSimulationNetwork(List<Node> tmpNodes, List<Link> tmpLinks, Network net) throws ENException {
@@ -692,7 +699,12 @@ protected long nextHyd() throws ENException, IOException {
         long hydstep = 0;
 
         if (simulationOutput != null)
-            AwareStep.write(simulationOutput, this, Htime);
+        {
+            if (qualitySim != null)
+                AwareStep.writeHydAndQual(simulationOutput, this, qualitySim, Rtime-Htime, Htime);
+            else
+                AwareStep.write(simulationOutput, this, Htime);
+        }
 
         if (Htime < pMap.getDuration())
             hydstep = timeStep();
@@ -708,6 +720,11 @@ else if (Htime < pMap.getDuration())
                 Rtime += pMap.getRstep();
         }
 
+        if (qualitySim != null) {
+            for (long i = 0, qstep = pMap.getQstep(), numQsteps = hydstep/pMap.getQstep(); i < numQsteps; i++) {
+                qualitySim.simulateSingleStep(nNodes, nLinks, qstep);
+            }
+        }
         return hydstep;
     }