Modifications to reduce memory usage

src/main/java/kieker/diagnosis/domain/AbstractOperationCall.java

@@ -48,10 +48,12 @@ public abstract class AbstractOperationCall<T extends AbstractOperationCall<T>>
 	}
 
 	public AbstractOperationCall(final String container, final String component, final String operation, final String failedCause) {
-		this.container = container;
-		this.component = component;
-		this.operation = operation;
-		this.failedCause = failedCause;
+		this.container = container.intern();
+		this.component = component.intern();
+		this.operation = operation.intern();
+		if (failedCause != null) {
+		  this.failedCause = failedCause.intern();
+		}
 	}
 
 	public void addChild(final T child) {
@@ -99,7 +101,10 @@ public abstract class AbstractOperationCall<T extends AbstractOperationCall<T>>
 	}
 
 	public final void setFailedCause(final String failedCause) {
-		this.failedCause = failedCause;
+	    this.failedCause = failedCause;
+	    if (this.failedCause != null) {
+	      this.failedCause =   this.failedCause.intern();
+	    }
 	}
 
 	public final boolean containsFailure() {

src/main/java/kieker/diagnosis/model/DataModel.java

@@ -82,43 +82,43 @@ public final class DataModel extends Observable {
 	}
 
 	public List<Trace> getTracesCopy() {
-		return new ArrayList<>(this.traces);
+		return this.traces;
 	}
 
 	public List<Trace> getFailedTracesCopy() {
-		return new ArrayList<>(this.failedTraces);
+		return this.failedTraces;
 	}
 
 	public List<Trace> getFailureContainingTracesCopy() {
-		return new ArrayList<>(this.failureContainingTraces);
+		return this.failureContainingTraces;
 	}
 
 	public List<AggregatedTrace> getAggregatedTracesCopy() {
-		return new ArrayList<>(this.aggregatedTraces);
+		return this.aggregatedTraces;
 	}
 
 	public List<AggregatedTrace> getFailedAggregatedTracesCopy() {
-		return new ArrayList<>(this.failedAggregatedTraces);
+		return this.failedAggregatedTraces;
 	}
 
 	public List<AggregatedTrace> getFailureContainingAggregatedTracesCopy() {
-		return new ArrayList<>(this.failureAggregatedContainingTraces);
+		return this.failureAggregatedContainingTraces;
 	}
 
 	public List<OperationCall> getOperationCalls() {
-		return new ArrayList<>(this.operationCalls);
+		return this.operationCalls;
 	}
 
 	public List<OperationCall> getFailedOperationCalls() {
-		return new ArrayList<>(this.failedOperationCalls);
+		return this.failedOperationCalls;
 	}
 
 	public List<AggregatedOperationCall> getAggregatedOperationCalls() {
-		return new ArrayList<>(this.aggregatedOperationCalls);
+		return this.aggregatedOperationCalls;
 	}
 
 	public List<AggregatedOperationCall> getAggregatedFailedOperationCalls() {
-		return new ArrayList<>(this.aggregatedFailedOperationCalls);
+		return this.aggregatedFailedOperationCalls;
 	}
 
 	public TimeUnit getTimeUnit() {

src/main/java/kieker/diagnosis/model/importer/stages/AggregatedTraceStatisticsDecorator.java

@@ -19,6 +19,7 @@ package kieker.diagnosis.model.importer.stages;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
+import java.util.concurrent.atomic.AtomicLong;
 
 import kieker.diagnosis.domain.AggregatedOperationCall;
 import kieker.diagnosis.domain.AggregatedTrace;
@@ -32,11 +33,16 @@ import kieker.diagnosis.domain.Trace;
  */
 public final class AggregatedTraceStatisticsDecorator extends AbstractStage<AggregatedTrace, AggregatedTrace> {
 
+  private long counter;
+  
 	@Override
 	public void execute(final AggregatedTrace trace) {
 		addNumberOfCalls(trace.getRootOperationCall(), trace.getTraces().size());
 		addDurationStatistics(trace);
 
+		// The references are no longer needed
+		trace.getTraces().clear();
+		
 		super.send(trace);
 	}
 

src/main/java/kieker/diagnosis/model/importer/stages/LegacyTraceReconstructor.java

@@ -52,6 +52,7 @@ final class LegacyTraceReconstructor extends AbstractStage<OperationExecutionRec
 		traceBuffer.handleEvent(input);
 		if (traceBuffer.isTraceComplete()) {
 			final Trace trace = traceBuffer.reconstructTrace();
+			traceBuffers.remove(traceID);
 			super.send(trace);
 		}
 	}

src/main/java/kieker/diagnosis/model/importer/stages/TraceReconstructor.java

@@ -55,7 +55,7 @@ final class TraceReconstructor extends AbstractStage<IFlowRecord, Trace> {
 
 		this.traceBuffers.put(traceID, newTraceBuffer);
 	}
-
+	
 	private void handleOperationEventRecord(final AbstractOperationEvent input) {
 		final long traceID = input.getTraceId();
 		final TraceBuffer traceBuffer = this.traceBuffers.get(traceID);
@@ -63,9 +63,12 @@ final class TraceReconstructor extends AbstractStage<IFlowRecord, Trace> {
 		traceBuffer.handleEvent(input);
 		if (traceBuffer.isTraceComplete()) {
 			final Trace trace = traceBuffer.reconstructTrace();
+			traceBuffers.remove(traceID);
 			super.send(trace);
 		}
 	}
+	
+	
 
 	private static final class TraceBuffer {