...

src/explorviz/live_trace_processing/filter/reduction/TracesSummarizationBuffer.java

 package explorviz.live_trace_processing.filter.reduction;
 
-import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map.Entry;
@@ -39,15 +38,15 @@ class TracesSummarizationBuffer {
 				final AbstractEventRecord event = aggregatedRecords.get(i);
 				final AbstractEventRecord event2 = records.get(i);
 
+				final List<HostApplicationMetaDataRecord> hostMetaList1 = event
+						.getHostApplicationMetadataList();
+				final List<HostApplicationMetaDataRecord> hostMetaList2 = event2
+						.getHostApplicationMetadataList();
+
 				if (event instanceof AbstractBeforeEventRecord) {
 					final AbstractBeforeEventRecord abstractBeforeEventRecord = (AbstractBeforeEventRecord) event;
 					final AbstractBeforeEventRecord abstractBeforeEventRecord2 = (AbstractBeforeEventRecord) event2;
 
-					final List<HostApplicationMetaDataRecord> hostMetaList1 = event
-							.getHostApplicationMetadataList();
-					final List<HostApplicationMetaDataRecord> hostMetaList2 = event2
-							.getHostApplicationMetadataList();
-
 					final List<RuntimeStatisticInformation> runtimeList1 = abstractBeforeEventRecord
 							.getRuntimeStatisticInformationList();
 					final List<RuntimeStatisticInformation> runtimeList2 = abstractBeforeEventRecord2
@@ -78,31 +77,24 @@ class TracesSummarizationBuffer {
 
 					for (final Entry<HostApplicationMetaDataRecord, RuntimeStatisticInformation> entry : toAdd
 							.entrySet()) {
-						hostMetaList1.add(entry.getKey());
-						final RuntimeStatisticInformation runtime2 = entry.getValue();
-						if (!runtime2.isInitialized()) {
-							runtime2.makeAccumulator(getRightObjectId(abstractBeforeEventRecord2));
+						if (entry.getKey() != null) {
+							hostMetaList1.add(entry.getKey());
+							final RuntimeStatisticInformation runtime2 = entry.getValue();
+							if (!runtime2.isInitialized()) {
+								runtime2.makeAccumulator(getRightObjectId(abstractBeforeEventRecord2));
+							}
+							runtimeList1.add(runtime2);
 						}
-						runtimeList1.add(runtime2);
 					}
 				} else {
-					final List<HostApplicationMetaDataRecord> hostMetaList1 = event
-							.getHostApplicationMetadataList();
-					final List<HostApplicationMetaDataRecord> hostMetaList2 = event2
-							.getHostApplicationMetadataList();
-
-					final List<HostApplicationMetaDataRecord> toAdd = new ArrayList<HostApplicationMetaDataRecord>(
-							2);
-
 					for (int j = 0; j < hostMetaList2.size(); j++) {
-						final int indexInHostList1 = indexOfHost(hostMetaList2.get(j),
-								hostMetaList1);
-						if (indexInHostList1 == -1) {
-							// not found, so insert later
-							toAdd.add(hostMetaList2.get(j));
+						final HostApplicationMetaDataRecord host2 = hostMetaList2.get(j);
+						final int indexInHostList1 = indexOfHost(host2, hostMetaList1);
+						if ((indexInHostList1 == -1) && (host2 != null)) {
+							// not found, so insert
+							hostMetaList1.add(host2);
 						}
 					}
-					hostMetaList1.addAll(toAdd);
 				}
 			}
 		}