diff --git a/AlgebraicDataflowArchitectureModel/src/application/simulator/InputEventCellEditor.java b/AlgebraicDataflowArchitectureModel/src/application/simulator/InputEventCellEditor.java
index 46bc39a..476c942 100644
--- a/AlgebraicDataflowArchitectureModel/src/application/simulator/InputEventCellEditor.java
+++ b/AlgebraicDataflowArchitectureModel/src/application/simulator/InputEventCellEditor.java
@@ -75,6 +75,7 @@
 	protected int minimumWidth = DEFAULT_MIN_WIDTH;
 	protected int minimumHeight = DEFAULT_MIN_HEIGHT;
 
+	private SimulatorWindow window;
 	private Object editingCell;
 	private EventObject trigger;
 	private JComboBox<String> comboBox;
@@ -84,8 +85,8 @@
 	private Editor editor;
 	private boolean bReflectingArchitectureModel = false;
 	
-	public InputEventCellEditor(mxGraphComponent graphComponent, Simulator simulator, Editor editor) {
-		this.graphComponent = graphComponent;
+	public InputEventCellEditor(SimulatorWindow window, mxGraphComponent graphComponent, Simulator simulator, Editor editor) {		this.graphComponent = graphComponent;
+		this.window = window;
 		this.simulator = simulator;
 		this.editor = editor;
 	}
@@ -109,26 +110,8 @@
 			ArrayList<Expression> eventMessages = new ArrayList<>();//messageList
 			ResourcePath eventResPath = null;
 
-			for(Channel ch : simulator.getModel().getInputChannels()) {//all channel
-				if(((DataTransferChannel)ch).getInputResources().size()== 0) {//ioch Or normalch
-					for(ChannelMember out: ((DataTransferChannel)ch).getOutputChannelMembers()) {
-						ResourcePath resPath = out.getResource();
-						if(resId.isInstanceOf(resPath)) {//account.uid == acounts.123
-							eventResPath = resPath;
-							eventChs.add(((DataTransferChannel)ch));
-							String message = null;
-							Expression mesExp = out.getStateTransition().getMessageExpression();//sync(a,b)
-							eventMessages.add(mesExp);
-							if(mesExp instanceof Term) {
-								message = ((Term) mesExp).getSymbol().toString();//sync
-							}else if(mesExp instanceof Variable) {
-								message = ((Variable) mesExp).getName();//x,y,z..
-							}
-							messages.add(message);//pulldown 
-							
-						}
-					}
-				}
+			for (Channel ch: simulator.getModel().getInputChannels()) {//all channel
+				eventResPath = getSelectableMessages(ch, resId, eventChs, messages, eventMessages, eventResPath);
 			}
 			    
 			if(messages.isEmpty()) {
@@ -140,7 +123,7 @@
 			JPanel eventChoice = new JPanel();
 			eventChoice.add(event);//FirstEventChoice
 			
-			int ret = JOptionPane.showConfirmDialog(null, eventChoice, "Event Choice", JOptionPane.OK_CANCEL_OPTION);
+			int ret = JOptionPane.showConfirmDialog(window, eventChoice, "Event Choice", JOptionPane.OK_CANCEL_OPTION);
 			if (ret == JOptionPane.OK_OPTION) {
 				
 				JPanel inputEvent = new JPanel();
@@ -157,22 +140,22 @@
 				JTextArea textArea = new JTextArea(eventMessages.get(eventNum).toString(), 10, 30);//EventInput
 				inputEvent.add(textArea);
 			
-				int approve = JOptionPane.showConfirmDialog(null, inputEvent, "Event Code", JOptionPane.OK_CANCEL_OPTION);
+				int approve = JOptionPane.showConfirmDialog(window, inputEvent, "Event Code", JOptionPane.OK_CANCEL_OPTION);
 				if (approve == JOptionPane.OK_OPTION) {
 					try {
 					
-					TokenStream stream = new Parser.TokenStream();
-					Parser parser = new Parser(stream);
-					stream.addLine(textArea.getText());
-					Expression eventMessage = parser.parseTerm(stream,simulator.getModel());
-					
-					Event newEvent = new Event(eventChs.get(eventNum), eventMessage, eventResPath, simulator.getCurState().getResource(resId)); 
-					simulator.transition(newEvent);
-
-//					SimulationLayout layout =  new SimulationLayout(simulator.getCurState());
-//					layout.constructSimulateGraph(graph, simulator);
-
-					graphComponent.setCellEditor(new InputEventCellEditor(graphComponent, simulator, this.editor));
+						TokenStream stream = new Parser.TokenStream();
+						Parser parser = new Parser(stream);
+						stream.addLine(textArea.getText());
+						Expression eventMessage = parser.parseTerm(stream,simulator.getModel());
+						
+						Event newEvent = new Event(eventChs.get(eventNum), eventMessage, eventResPath, simulator.getCurState().getResource(resId)); 
+						simulator.transition(newEvent);
+	
+//						SimulationLayout layout =  new SimulationLayout(simulator.getCurState());
+//						layout.constructSimulateGraph(graph, simulator);
+	
+						graphComponent.setCellEditor(new InputEventCellEditor(window, graphComponent, simulator, this.editor));
 					
 					} catch (ParameterizedIdentifierIsFutureWork | ResolvingMultipleDefinitionIsFutureWork
 							| InvalidMessage | UnificationFailed | ValueUndefined | ExpectedRightBracket | WrongJsonExpression | ExpectedColon | ExpectedDoubleQuotation e) {
@@ -180,8 +163,6 @@
 					}
 				}
 			}
-			//resource
-		return;
 		}
 
 		mxCellState state = graphComponent.getGraph().getView().getState(cell);
@@ -203,7 +184,34 @@
 			}
 		}
 	}
-
+	
+	private ResourcePath getSelectableMessages(Channel ch, ResourceIdentifier resId,
+			ArrayList<DataTransferChannel> eventChs, ArrayList<String> messages, ArrayList<Expression> eventMessages,
+			ResourcePath eventResPath) {
+		if (((DataTransferChannel)ch).getInputResources().size() == 0) {//ioch Or normalch
+			for (ChannelMember out: ((DataTransferChannel)ch).getOutputChannelMembers()) {
+				ResourcePath resPath = out.getResource();
+				if (!out.isOutside() && resId.isInstanceOf(resPath)) {//account.uid == acounts.123
+					eventResPath = resPath;
+					eventChs.add(((DataTransferChannel)ch));
+					String message = null;
+					Expression mesExp = out.getStateTransition().getMessageExpression();//sync(a,b)
+					eventMessages.add(mesExp);
+					if (mesExp instanceof Term) {
+						message = ((Term) mesExp).getSymbol().toString();//sync
+					} else if(mesExp instanceof Variable) {
+						message = ((Variable) mesExp).getName();//x,y,z..
+					}
+					messages.add(message);//pulldown 
+				}
+			}
+			for (Channel childCh: ch.getChildren()) {
+				eventResPath = getSelectableMessages(childCh, resId, eventChs, messages, eventMessages, eventResPath);
+			}
+		}
+		return eventResPath;
+	}
+	
 //	private mxGraph constructNextSimulateGraph(Set<Resource> simulateRes, DataTransferModel model,DataFlowGraph dataFlowGraph, mxGraph nextGraph) {
 //		bReflectingArchitectureModel = true;
 //		((mxGraphModel) nextGraph.getModel()).clear();
diff --git a/AlgebraicDataflowArchitectureModel/src/application/simulator/SimulatorWindow.java b/AlgebraicDataflowArchitectureModel/src/application/simulator/SimulatorWindow.java
index 6dfb078..adfd10f 100644
--- a/AlgebraicDataflowArchitectureModel/src/application/simulator/SimulatorWindow.java
+++ b/AlgebraicDataflowArchitectureModel/src/application/simulator/SimulatorWindow.java
@@ -131,8 +131,8 @@
 		simulator = new Simulator(model);
 		SimulationLayout layout =  new SimulationLayout(simulator.getCurState());
 		layout.constructSimulateGraph(graph, simulator);
-	    graphComponent.setCellEditor(new InputEventCellEditor(graphComponent, simulator, this.editor));
-	    simulator.addSystemReceiver(this);
+        graphComponent.setCellEditor(new InputEventCellEditor(this, graphComponent, simulator, this.editor));
+        simulator.addSystemReceiver(this);
 	    
 		menuBar = new SimulatorMenuBar(this);
 		setJMenuBar(menuBar);
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/CodeGeneratorFromDataFlowGraph.java b/AlgebraicDataflowArchitectureModel/src/generators/CodeGeneratorFromDataFlowGraph.java
index ab82982..fc6b3f4 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/CodeGeneratorFromDataFlowGraph.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/CodeGeneratorFromDataFlowGraph.java
@@ -59,6 +59,7 @@
 		List<Map.Entry<ResourceHierarchy, VariableDeclaration>> constructorParams = new ArrayList<>();
 		List<Map.Entry<ResourceHierarchy, String>> constructorStatements = new ArrayList<>();
 		Map<MethodDeclaration, Map.Entry<Expression, ResourceHierarchy>> updateStatements = new HashMap<>();
+		Map<ResourceHierarchy, Set<ResourceHierarchy>> childGetters = new HashMap<>();
 		
 		// For each components (1st pass).
 		for (Node componentNode: components) {
@@ -105,9 +106,10 @@
 					
 					// Declare the accessor method in the main component to call the getter method.
 					declareAccessorInMainComponent(mainComponent, resourceNode, stateGetter, langSpec);
-					
+				}
+				if (component != null) {
 					// Declare the getter methods in this resource to obtain the children resources.
-					declareChildGetterMethod(resourceNode, component, langSpec);
+					declareChildGetterMethod(resourceNode, component, childGetters, langSpec);
 				}
 			}
 		}
@@ -236,7 +238,7 @@
 		while (termEntItr.hasNext()) {
 			Entry<Position, Term> termEnt = termEntItr.next();
 			Term jsonTerm = termEnt.getValue();
-			if (jsonTerm.getType().equals(replacedJsonType)) {
+			if (jsonTerm.getType() != null && jsonTerm.getType().equals(replacedJsonType)) {
 				MethodDeclaration childConstructor = getConstructor(childComponent);
 				List<String> params = new ArrayList<>();
 				for (VariableDeclaration var: childConstructor.getParameters()) {
@@ -394,7 +396,7 @@
 						// The child has a component.
 						childType = new Type(childTypeName, childTypeName);
 						String fieldName = langSpec.toVariableName(childTypeName);
-						FieldDeclaration stateField = langSpec.newFieldDeclaration(childType, fieldName, langSpec.getFieldInitializer(resStateType, resourceNode.getResourceHierarchy().getInitialValue()));
+						FieldDeclaration stateField = langSpec.newFieldDeclaration(childType, fieldName, langSpec.getConstructorInvocation(childTypeName, new ArrayList<>()));
 						component.addField(stateField);
 					}
 				}
@@ -714,9 +716,13 @@
 		}
 	}
 	
-	private void declareChildGetterMethod(ResourceNode resourceNode, TypeDeclaration component, ILanguageSpecific langSpec) {
+	private void declareChildGetterMethod(ResourceNode resourceNode, TypeDeclaration component, Map<ResourceHierarchy, Set<ResourceHierarchy>> childGetters, ILanguageSpecific langSpec) {
 		// Declare the getter methods in this resource to obtain the children resources.
-		Set<ResourceHierarchy> children = new HashSet<>();
+		Set<ResourceHierarchy> children = childGetters.get(resourceNode.getResourceHierarchy());
+		if (children == null) {
+			children = new HashSet<>();
+			childGetters.put(resourceNode.getResourceHierarchy(), children);
+		}
 		for (ResourceNode child: resourceNode.getChildren()) {
 			if (generatesComponent(child.getResourceHierarchy())) {
 				// A component for the child is generated.
@@ -724,12 +730,13 @@
 					children.add(child.getResourceHierarchy());
 					List<VariableDeclaration> params = new ArrayList<>();
 					int v = 1;
-					for (Selector param: child.getSelectors()) {
-						if (param.getExpression() instanceof Variable) {
-							Variable var = (Variable) param.getExpression();
+					Expression param = child.getPrimaryResourcePath().getLastParam();
+					if (param != null) {
+						if (param instanceof Variable) {
+							Variable var = (Variable) param;
 							params.add(langSpec.newVariableDeclaration(var.getType(), var.getName()));
-						} else if (param.getExpression() instanceof Term) {
-							Term var = (Term) param.getExpression();
+						} else if (param instanceof Term) {
+							Term var = (Term) param;
 							params.add(langSpec.newVariableDeclaration(var.getType(), "v" + v));
 						}
 						v++;
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java b/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java
index e86cc63..7c9ad00 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JavaCodeGenerator.java
@@ -133,6 +133,7 @@
 		Map<ResourceHierarchy, Map<String, MethodDeclaration>> updates = new HashMap<>();
 		Map<ResourceHierarchy, Map<String, MethodDeclaration>> inputs = new HashMap<>();
 		List<Map.Entry<ResourceHierarchy, FieldDeclaration>> fields = new ArrayList<>();
+		Map<ResourceHierarchy, Set<ResourceHierarchy>> childGetters = new HashMap<>();
 		List<Map.Entry<ResourceHierarchy, VariableDeclaration>> constructorParams = new ArrayList<>();
 
 		Map<ResourceHierarchy, Set<ResourceHierarchy>> dependedRootComponentGraph = getDependedRootComponentGraph(model);
@@ -259,7 +260,7 @@
 										// The child has a component.
 										childType = new Type(childTypeName, childTypeName);
 										String fieldName = toVariableName(childTypeName);
-										component.addField(new FieldDeclaration(childType, fieldName, getInitializer(res)));							
+										component.addField(new FieldDeclaration(childType, fieldName, "new " + childTypeName + "()"));
 									}
 								}
 							}
@@ -272,9 +273,14 @@
 					
 					// Declare the accessor method in the main type to call the getter method.
 					declareAccessorMethodInMainComponent(resourceNode, mainComponent);
-					
+				}
+				if (component != null) {
 					// Declare the getter methods to obtain the children resources.
-					Set<ResourceHierarchy> children = new HashSet<>();
+					Set<ResourceHierarchy> children = childGetters.get(resourceNode.getResourceHierarchy());
+					if (children == null) {
+						children = new HashSet<>();
+						childGetters.put(resourceNode.getResourceHierarchy(), children);
+					}
 					for (ResourceNode child: resourceNode.getChildren()) {
 						if (generatesComponent(child.getResourceHierarchy())) {
 							// A component for the child is generated.
@@ -282,12 +288,13 @@
 								children.add(child.getResourceHierarchy());
 								List<VariableDeclaration> params = new ArrayList<>();
 								int v = 1;
-								for (Selector param: child.getSelectors()) {
-									if (param.getExpression() instanceof Variable) {
-										Variable var = (Variable) param.getExpression();
+								Expression param = child.getPrimaryResourcePath().getLastParam();
+								if (param != null) {
+									if (param instanceof Variable) {
+										Variable var = (Variable) param;
 										params.add(new VariableDeclaration(var.getType(), var.getName()));
-									} else if (param.getExpression() instanceof Term) {
-										Term var = (Term) param.getExpression();
+									} else if (param instanceof Term) {
+										Term var = (Term) param;
 										params.add(new VariableDeclaration(var.getType(), "v" + v));
 									}
 									v++;
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JavaMethodBodyGenerator.java b/AlgebraicDataflowArchitectureModel/src/generators/JavaMethodBodyGenerator.java
index 08bc6ec..4ab9dd3 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JavaMethodBodyGenerator.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JavaMethodBodyGenerator.java
@@ -832,7 +832,7 @@
 		while (termEntItr.hasNext()) {
 			Entry<Position, Term> termEnt = termEntItr.next();
 			Term jsonTerm = termEnt.getValue();
-			if (jsonTerm.getType().equals(replacedJsonType)) {
+			if (jsonTerm.getType() != null && jsonTerm.getType().equals(replacedJsonType)) {
 				String constructorInvocation = "new " + replacingClassName + "(";
 				MethodDeclaration childConstructor = getConstructor(childComponent);
 				String delimiter = "";
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java b/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java
index 78a04d2..33fae7a 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JerseyCodeGenerator.java
@@ -136,6 +136,7 @@
 		Map<ResourceHierarchy, Map<String, MethodDeclaration>> updates = new HashMap<>();
 		Map<ResourceHierarchy, Map<String, MethodDeclaration>> inputs = new HashMap<>();
 		List<Map.Entry<ResourceHierarchy, FieldDeclaration>> fields = new ArrayList<>();
+		Map<ResourceHierarchy, Set<ResourceHierarchy>> childGetters = new HashMap<>();
 		Map<ResourceHierarchy, MethodDeclaration> getterAccessors = new HashMap<>();
 		Map<ResourceHierarchy, MethodDeclaration> inputAccessors = new HashMap<>();
 		Map<ResourceHierarchy, Map<String, VariableDeclaration>> constructorParams = new HashMap<>();
@@ -203,7 +204,7 @@
 										// The child has a component.
 										childType = new Type(childTypeName, childTypeName);
 										String fieldName = toVariableName(childTypeName);
-										component.addField(new FieldDeclaration(childType, fieldName, getInitializer(res)));							
+										component.addField(new FieldDeclaration(childType, fieldName, "new " + childTypeName + "()"));
 									}
 								}
 							}
@@ -218,9 +219,14 @@
 						stateGetter.addAnnotation(new Annotation("GET"));
 					}
 					component.addMethod(stateGetter);
-					
+				}
+				if (component != null) {
 					// Declare the getter methods to obtain the children resources.
-					Set<ResourceHierarchy> children = new HashSet<>();
+					Set<ResourceHierarchy> children = childGetters.get(resourceNode.getResourceHierarchy());
+					if (children == null) {
+						children = new HashSet<>();
+						childGetters.put(resourceNode.getResourceHierarchy(), children);
+					}
 					for (ResourceNode child: resourceNode.getChildren()) {
 						if (generatesComponent(child.getResourceHierarchy())) {
 							// The child generates a component.
@@ -228,7 +234,8 @@
 								children.add(child.getResourceHierarchy());
 								List<VariableDeclaration> pathParams = new ArrayList<>();
 								int v = 1;
-								for (Expression pathParam: child.getPrimaryResourcePath().getPathParams()) {
+								Expression pathParam = child.getPrimaryResourcePath().getLastParam();
+								if (pathParam != null) {
 									if (pathParam instanceof Variable) {
 										Variable var = (Variable) pathParam;
 										pathParams.add(new VariableDeclaration(var.getType(), var.getName()));
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JerseyMethodBodyGenerator.java b/AlgebraicDataflowArchitectureModel/src/generators/JerseyMethodBodyGenerator.java
index 4efb2dd..d695463 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JerseyMethodBodyGenerator.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JerseyMethodBodyGenerator.java
@@ -952,7 +952,7 @@
 		while (termEntItr.hasNext()) {
 			Entry<Position, Term> termEnt = termEntItr.next();
 			Term jsonTerm = termEnt.getValue();
-			if (jsonTerm.getType().equals(replacedJsonType)) {
+			if (jsonTerm.getType() != null && jsonTerm.getType().equals(replacedJsonType)) {
 				String constructorInvocation = "new " + replacingClassName + "(";
 				MethodDeclaration childConstructor = getConstructor(childComponent);
 				String delimiter = "";
diff --git a/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java b/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java
index cfef320..95c2b47 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java
@@ -75,8 +75,13 @@
 	
 	public <T extends Expression> HashMap<Position, T> getSubTerms(Class<T> clazz) {
 		HashMap<Position, T> subTerms = new HashMap<>();
-		if (clazz == this.getClass()) {
-			subTerms.put(new Position(), (T) this);
+		Class thisClass = this.getClass();
+		while (thisClass != null) {
+			if (clazz == thisClass) {
+				subTerms.put(new Position(), (T) this);
+				break;
+			}
+			thisClass = thisClass.getSuperclass();
 		}
 		for (int i = 0; i < children.size(); i++) {
 			HashMap<Position, T> terms = children.get(i).getSubTerms(clazz);
diff --git a/AlgebraicDataflowArchitectureModel/src/models/algebra/Type.java b/AlgebraicDataflowArchitectureModel/src/models/algebra/Type.java
index e408a54..3b573d2 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/algebra/Type.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/algebra/Type.java
@@ -73,7 +73,7 @@
 	
 	public boolean isAncestorOf(Type another) {
 		if (this.equals(another)) return true;
-		if (another.getParentTypes() == null) return false;
+		if (another == null || another.getParentTypes() == null) return false;
 		for (Type anothersParentType: another.getParentTypes()) {
 			if (isAncestorOf(anothersParentType)) return true;
 		}
diff --git a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/DataConstraintModel.java b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/DataConstraintModel.java
index 0962ce2..a76879f 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/DataConstraintModel.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/DataConstraintModel.java
@@ -178,7 +178,19 @@
 			return new Constant(Integer.toString(-Integer.parseInt(sArg)));
 		}
 	});
-	public static final Symbol eq = new Symbol(Parser.EQ, 2, Symbol.Type.INFIX, "==", Symbol.Type.INFIX, new Symbol.ICalculator() {
+	public static final Symbol eq = new Symbol(Parser.EQ, 2, Symbol.Type.INFIX, new Symbol.IImplGenerator() {
+		@Override
+		public String generate(Type type, Type[] childrenTypes, String[] children, String[] childrenSideEffects, String[] sideEffect) {
+			for (String s: childrenSideEffects) {
+				sideEffect[0] += s;
+			}
+			if (childrenTypes[0].equals(typeString) && childrenTypes[1].equals(typeString)) {
+				return children[0] + ".equals(" + children[1] + ")";
+			}
+			return "(" + children[0] + "==" + children[1] + ")";
+		}
+		
+	}, new Symbol.ICalculator() {
 		@Override
 		public Expression calculate(List<Expression> args) {
 			if (!(args.get(0) instanceof Constant)) {
@@ -201,7 +213,7 @@
 			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
 				result = (Integer.parseInt(sArg0) == Integer.parseInt(sArg1));
 			} else if (arg0.getType().equals(typeString) || arg1.getType().equals(typeString)) {
-				result = (sArg0.toString().equals(sArg1.toString()));
+				result = sArg0.toString().equals(sArg1.toString());
 			}
 			if (result) {
 				return new Constant(true_);
@@ -210,7 +222,19 @@
 			}
 		}
 	});
-	public static final Symbol neq = new Symbol(Parser.NEQ, 2, Symbol.Type.INFIX, "!=", Symbol.Type.INFIX, new Symbol.ICalculator() {
+	public static final Symbol neq = new Symbol(Parser.NEQ, 2, Symbol.Type.INFIX, new Symbol.IImplGenerator() {
+		@Override
+		public String generate(Type type, Type[] childrenTypes, String[] children, String[] childrenSideEffects, String[] sideEffect) {
+			for (String s: childrenSideEffects) {
+				sideEffect[0] += s;
+			}
+			if (childrenTypes[0].equals(typeString) && childrenTypes[1].equals(typeString)) {
+				return "!" + children[0] + ".equals(" + children[1] + ")";
+			}
+			return "(" + children[0] + "!=" + children[1] + ")";
+		}
+		
+	}, new Symbol.ICalculator() {
 		@Override
 		public Expression calculate(List<Expression> args) {
 			if (!(args.get(0) instanceof Constant)) {
@@ -232,6 +256,8 @@
 				result = (Long.parseLong(sArg0) != Long.parseLong(sArg1));
 			} else if (arg0.getType().equals(typeInt) || arg1.getType().equals(typeInt)) {
 				result = (Integer.parseInt(sArg0) != Integer.parseInt(sArg1));
+			} else if (arg0.getType().equals(typeString) || arg1.getType().equals(typeString)) {
+				result = !(sArg0.toString().equals(sArg1.toString()));
 			}
 			if (result) {
 				return new Constant(true_);
@@ -507,7 +533,7 @@
 					}
 				}
 			}
-			return new Constant(false_);
+			return null;
 		}
 	});
 	public static final Symbol nil = new Symbol("nil", 0, Symbol.Type.PREFIX, new Symbol.IImplGenerator() {
diff --git a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/ResourceHierarchy.java b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/ResourceHierarchy.java
index 7412266..be99827 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/ResourceHierarchy.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/ResourceHierarchy.java
@@ -97,6 +97,7 @@
 	
 	public ResourceHierarchy(ResourceHierarchy parent, Expression parameterExp, Type resourceStateType) {
 		this.parent = parent;
+		if (this.children == null) this.children = new HashSet<>();
 		this.resourceName = null;
 		this.numParameters = 1;
 		this.resourceStateType = resourceStateType;
@@ -120,6 +121,7 @@
 	
 	public ResourceHierarchy(ResourceHierarchy parent, int numParameters, Type resourceStateType) {
 		this.parent = parent;
+		if (this.children == null) this.children = new HashSet<>();
 		this.resourceName = null;
 		this.numParameters = numParameters;
 		this.resourceStateType = resourceStateType;
diff --git a/AlgebraicDataflowArchitectureModel/src/parser/Parser.java b/AlgebraicDataflowArchitectureModel/src/parser/Parser.java
index 3362f4f..abec1de 100644
--- a/AlgebraicDataflowArchitectureModel/src/parser/Parser.java
+++ b/AlgebraicDataflowArchitectureModel/src/parser/Parser.java
@@ -166,11 +166,14 @@
 		}
 		String leftBracket = stream.next();
 		if (leftBracket.equals(LEFT_BRACKET)) {
-			// has a selector
-			String selector = stream.next();
-			Variable var = parseVariable(stream, model, selector);
-			channel.addSelector(var);
-			String rightBracket = stream.next();
+			// has selectors
+			String rightBracket = null;
+			do {
+				String selector = stream.next();
+				Variable var = parseVariable(stream, model, selector);
+				channel.addSelector(var);
+				rightBracket = stream.next();
+			} while (rightBracket.equals(COMMA));
 			if (!rightBracket.equals(RIGHT_BRACKET)) throw new ExpectedRightBracket(stream.getLine());
 			leftBracket = stream.next();
 		}
diff --git a/AlgebraicDataflowArchitectureModel/src/simulator/Event.java b/AlgebraicDataflowArchitectureModel/src/simulator/Event.java
index 58a9df8..b0feb2b 100644
--- a/AlgebraicDataflowArchitectureModel/src/simulator/Event.java
+++ b/AlgebraicDataflowArchitectureModel/src/simulator/Event.java
@@ -235,8 +235,11 @@
 			for (ChannelMember depending: dependency.keySet()) {
 				toResolve.remove(depending);
 			}
+			Expression messageConstraint = null;
+			if ((messageConstraint = getMessage()) instanceof Term) {
+				unifiedMessage = (Term) messageConstraint;
+			}
 			for (ChannelMember leafMember: toResolve) {
-				Expression messageConstraint = null;
 				if (channel.getInputChannelMembers().contains(leafMember)) {
 					// Calculate message constraint from an input state transition
 					messageConstraint = channel.calcMessageConstraintForInputMember(leafMember, null, resouceStateAccessor, null, substitutedPositionsInMessageFromChannels);
@@ -287,7 +290,6 @@
 					}
 					
 					// Calculate message constraint
-					Expression messageConstraint = null;
 					if (channel.getInputChannelMembers().contains(dependingMem)) {
 						// Calculate message constraint from an input state transition
 						messageConstraint = channel.calcMessageConstraintForInputMember(dependingMem, null, resouceStateAccessor, null, substitutedPositionsInMessageFromChannels);
diff --git a/AlgebraicDataflowArchitectureModel/src/simulator/ResourceIdentifier.java b/AlgebraicDataflowArchitectureModel/src/simulator/ResourceIdentifier.java
index d454391..d0463cf 100644
--- a/AlgebraicDataflowArchitectureModel/src/simulator/ResourceIdentifier.java
+++ b/AlgebraicDataflowArchitectureModel/src/simulator/ResourceIdentifier.java
@@ -24,7 +24,12 @@
 	}
 
 	public void setPathParam(int paramIdx, Constant param) {
-		pathParams.set(paramIdx, param);
+		if (paramIdx < pathParams.size()) {
+			pathParams.set(paramIdx, param);
+			if (parent != null) {
+				((ResourceIdentifier) parent).setPathParam(paramIdx, param);
+			}
+		}
 	}
 	
 	public boolean equals(ResourceIdentifier another) {
diff --git a/AlgebraicDataflowArchitectureModel/src/simulator/Simulator.java b/AlgebraicDataflowArchitectureModel/src/simulator/Simulator.java
index 6197b03..56a9cb7 100644
--- a/AlgebraicDataflowArchitectureModel/src/simulator/Simulator.java
+++ b/AlgebraicDataflowArchitectureModel/src/simulator/Simulator.java
@@ -84,6 +84,7 @@
 	public SystemState transition(Event inputEvent) 
 			throws ParameterizedIdentifierIsFutureWork, ResolvingMultipleDefinitionIsFutureWork, InvalidMessage, UnificationFailed, ValueUndefined {
 		SystemState nextSystemState = new SystemState(curState);
+		inputEvent.updateDependingParameters(new ResourceStateValueProvider(curState, nextSystemState));
 		nextSystemState.addEvent(inputEvent);
 		
 		fireEvent(inputEvent, curState, nextSystemState);
@@ -174,16 +175,25 @@
 		if (channel.getOutputResources().size() > 0) {
 			// For each output resource, calculate the next state.
 			for (ChannelMember out: channel.getOutputChannelMembers()) {
+				// Calculate the next state expression.
 				Expression nextResState = null; 
 				if (!event.isInput()) {
 					nextResState = channel.deriveUpdateExpressionOf(out, resouceStateAccessor).getKey();
 				} else {
 					nextResState = channel.deriveUpdateExpressionOf(out, (Term) event.getMessage(), resouceStateAccessor);
 				}
-				ResourceIdentifier outResId = event.getOutputResourceIdentifier(out.getResource());
+				// Substitute each channel selector in the expression to a value.
+				for (Map.Entry<Selector, Constant> selestorAndVal: event.getChannelSelectorAndValues()) {
+					Expression selExp = selestorAndVal.getKey().getExpression();
+					if (nextResState instanceof Term && selExp instanceof Variable) {
+						nextResState = ((Term) nextResState).substitute((Variable) selExp, selestorAndVal.getValue());
+					}
+				}
 				if (nextResState instanceof Term) {
 					nextResState = ((Term) nextResState).reduce();
 				}
+				// Update the resource state.
+				ResourceIdentifier outResId = event.getOutputResourceIdentifier(out.getResource());
 				ResourceIdentifier updatedOutResId = nextSystemState.updateResourceState(outResId, nextResState);
 				while (updatedOutResId != null) {		// In addition to the target state, its descendants' states are also changed.
 					for (Event nextEvent: getNextEvents(updatedOutResId, curSystemState, nextSystemState)) {
@@ -203,22 +213,10 @@
 		}
 	}
 
-	private Set<Event> getNextEvents(ResourceIdentifier inResId, final SystemState curSystemState, final SystemState nextSystemState) 
+	private Set<Event> getNextEvents(ResourceIdentifier inResId, SystemState curSystemState, SystemState nextSystemState) 
 			throws ParameterizedIdentifierIsFutureWork, ResolvingMultipleDefinitionIsFutureWork, InvalidMessage, UnificationFailed, ValueUndefined {
 		Set<Event> nextEvents = new HashSet<>();
-		IResourceStateValueProvider resourceStateValueProvider = new IResourceStateValueProvider() {
-			@Override
-			public Expression getCurrentStateValueOf(ResourceIdentifier resId) {
-				if (curSystemState.getResource(resId) == null) return null;
-				return curSystemState.getResource(resId).getState().getValue();
-			}
-
-			@Override
-			public Expression getNextStateValueOf(ResourceIdentifier resId) {
-				if (nextSystemState.getResource(resId) == null) return null;
-				return nextSystemState.getResource(resId).getState().getValue();
-			}
-		};
+		IResourceStateValueProvider resourceStateValueProvider = new ResourceStateValueProvider(curSystemState, nextSystemState);
 		for (Map.Entry<DataTransferChannel, ChannelState> chEntry: nextSystemState.getChannelStates().entrySet()) {
 			DataTransferChannel channel = chEntry.getKey();
 			ChannelState nextChState = chEntry.getValue();
@@ -316,4 +314,26 @@
 		}
 		return nextEvents;
 	}
+	
+	private static class ResourceStateValueProvider implements IResourceStateValueProvider {
+		SystemState curSystemState;
+		SystemState nextSystemState;
+		
+		public ResourceStateValueProvider(SystemState curSystemState, SystemState nextSystemState) {
+			this.curSystemState = curSystemState;
+			this.nextSystemState = nextSystemState;
+		}
+		
+		@Override
+		public Expression getCurrentStateValueOf(ResourceIdentifier resId) {
+			if (curSystemState.getResource(resId) == null) return null;
+			return curSystemState.getResource(resId).getState().getValue();
+		}
+ 
+		@Override
+		public Expression getNextStateValueOf(ResourceIdentifier resId) {
+			if (nextSystemState.getResource(resId) == null) return null;
+			return nextSystemState.getResource(resId).getState().getValue();
+		}
+	};
 }
diff --git a/AlgebraicDataflowArchitectureModel/src/simulator/SystemState.java b/AlgebraicDataflowArchitectureModel/src/simulator/SystemState.java
index 645ed14..98f752e 100644
--- a/AlgebraicDataflowArchitectureModel/src/simulator/SystemState.java
+++ b/AlgebraicDataflowArchitectureModel/src/simulator/SystemState.java
@@ -12,6 +12,7 @@
 import models.algebra.Expression;
 import models.algebra.Term;
 import models.algebra.Type;
+import models.algebra.Variable;
 import models.dataConstraintModel.DataConstraintModel;
 import models.dataConstraintModel.JsonTerm;
 import models.dataConstraintModel.ListTerm;
@@ -88,9 +89,19 @@
 				ResourceIdentifier createdResource = null;
 				for (int i = 0; i < listValue.size(); i++) {
 					Expression childExp = new Constant(Integer.toString(i), DataConstraintModel.typeInt);
-					ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, 
-																						childExp, 
-																						resourceIdentifier.getResourceHierarchy().getChildren().iterator().next());
+					ResourceHierarchy childResourceHierarchy = null;
+					if (resourceIdentifier.getResourceHierarchy().getChildren() != null && resourceIdentifier.getResourceHierarchy().getChildren().size() > 0) {
+						childResourceHierarchy = resourceIdentifier.getResourceHierarchy().getChildren().iterator().next();
+					} else {
+						Type childResType = null;
+						if (listValue.get(i) instanceof Variable) {
+							childResType = ((Variable) listValue.get(i)).getType();
+						} else if (listValue.get(i) instanceof Term) {
+							childResType = ((Term) listValue.get(i)).getType();
+						}
+						childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1, childResType);
+					}
+					ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, childExp, childResourceHierarchy);
 					Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, listValue.get(i));
 					((ListResourceState) state).addChildState(childInfo.getKey());
 					createdResource = childInfo.getValue();
@@ -119,7 +130,13 @@
 					if (resourceIdentifier.getResourceHierarchy().getChildren() != null && resourceIdentifier.getResourceHierarchy().getChildren().size() > 0) {
 						childResourceHierarchy = resourceIdentifier.getResourceHierarchy().getChildren().iterator().next();
 					} else {
-						childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1);
+						Type childResType = null;
+						if (listValue.getChild(1) instanceof Variable) {
+							childResType = ((Variable) listValue.getChild(1)).getType();
+						} else if (listValue.getChild(1) instanceof Term) {
+							childResType = ((Term) listValue.getChild(1)).getType();
+						}
+						childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1, childResType);
 					}
 					ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, childExp, childResourceHierarchy);
 					Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, listValue.getChild(1));
@@ -136,9 +153,19 @@
 				ResourceIdentifier createdResource = null;
 				for (String key: mapValue.keySet()) {
 					Expression childExp = new Constant(key, DataConstraintModel.typeString);
-					ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, 
-																						childExp, 
-																						resourceIdentifier.getResourceHierarchy().getChildren().iterator().next());
+					ResourceHierarchy childResourceHierarchy = null;
+					if (resourceIdentifier.getResourceHierarchy().getChildren() != null && resourceIdentifier.getResourceHierarchy().getChildren().size() > 0) {
+						childResourceHierarchy = resourceIdentifier.getResourceHierarchy().getChildren().iterator().next();
+					} else {
+						Type childResType = null;
+						if (mapValue.get(key) instanceof Variable) {
+							childResType = ((Variable) mapValue.get(key)).getType();
+						} else if (mapValue.get(key) instanceof Term) {
+							childResType = ((Term) mapValue.get(key)).getType();
+						}
+						childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1, childResType);
+					}
+					ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, childExp, childResourceHierarchy);
 					Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, mapValue.get(key));
 					((MapResourceState) state).addChildState(key, childInfo.getKey());
 					createdResource = childInfo.getValue();
@@ -151,9 +178,19 @@
 				ResourceIdentifier createdResource = null;
 				for (String key: mapValue.keySet()) {
 					Expression childExp = new Constant(key, DataConstraintModel.typeString);
-					ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, 
-																						childExp, 
-																						resourceIdentifier.getResourceHierarchy().getChildren().iterator().next());
+					ResourceHierarchy childResourceHierarchy = null;
+					if (resourceIdentifier.getResourceHierarchy().getChildren() != null && resourceIdentifier.getResourceHierarchy().getChildren().size() > 0) {
+						childResourceHierarchy = resourceIdentifier.getResourceHierarchy().getChildren().iterator().next();
+					} else {
+						Type childResType = null;
+						if (mapValue.get(key) instanceof Variable) {
+							childResType = ((Variable) mapValue.get(key)).getType();
+						} else if (mapValue.get(key) instanceof Term) {
+							childResType = ((Term) mapValue.get(key)).getType();
+						}
+						childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1, childResType);
+					}
+					ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, childExp, childResourceHierarchy);
 					Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, mapValue.get(key));
 					((MapResourceState) state).addChildState(key, childInfo.getKey());
 					createdResource = childInfo.getValue();
@@ -180,7 +217,13 @@
 						if (resourceIdentifier.getResourceHierarchy().getChildren() != null && resourceIdentifier.getResourceHierarchy().getChildren().size() > 0) {
 							childResourceHierarchy = resourceIdentifier.getResourceHierarchy().getChildren().iterator().next();
 						} else {
-							childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1);
+							Type childResType = null;
+							if (mapValue.getChild(2) instanceof Variable) {
+								childResType = ((Variable) mapValue.getChild(2)).getType();
+							} else if (mapValue.getChild(2) instanceof Term) {
+								childResType = ((Term) mapValue.getChild(2)).getType();
+							}
+							childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1, childResType);
 						}
 						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, childExp, childResourceHierarchy);
 						String childId = ((Constant) childExp).toString();
@@ -207,7 +250,13 @@
 						}
 					}
 					if (childResourceHierarchy == null) {
-						childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), memberName);
+						Type childResType = null;
+						if (jsonValue.get(key) instanceof Variable) {
+							childResType = ((Variable) jsonValue.get(key)).getType();
+						} else if (jsonValue.get(key) instanceof Term) {
+							childResType = ((Term) jsonValue.get(key)).getType();
+						}
+						childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), memberName, childResType);
 					}
 					ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, memberName, childResourceHierarchy);
 					Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, jsonValue.get(key));
@@ -236,7 +285,13 @@
 							}
 						}
 						if (childResourceHierarchy == null) {
-							childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), memberName);
+							Type childResType = null;
+							if (jsonValue.getChild(2) instanceof Variable) {
+								childResType = ((Variable) jsonValue.getChild(2)).getType();
+							} else if (jsonValue.getChild(2) instanceof Term) {
+								childResType = ((Term) jsonValue.getChild(2)).getType();
+							}
+							childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), memberName, childResType);
 						}
 						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, memberName, childResourceHierarchy);
 						String childId = ((Constant) childExp).toString();
@@ -275,12 +330,11 @@
 	}
 
 	public Map.Entry<ResourceState, ResourceIdentifier> createResourceState(ResourceIdentifier resourceIdentifier, Expression resStateValue) {
-//		Type resType = null;
-//		if (resStateValue instanceof Term) {
-//			resType = ((Term) resStateValue).getType();
-//			resStateValue = ((Term) resStateValue).reduce();
-//		}
 		Type resType = resourceIdentifier.getResourceStateType();
+		if (resType == null && resStateValue instanceof Term) {
+			resType = ((Term) resStateValue).getType();
+			resStateValue = ((Term) resStateValue).reduce();
+		}
 		if (resType != null) {
 			if (DataConstraintModel.typeList.isAncestorOf(resType)) {
 				if (resStateValue instanceof Constant) {
@@ -290,9 +344,19 @@
 					Map.Entry<ResourceState, ResourceIdentifier> createInfo = null;
 					for (int i = 0; i < listValue.size(); i++) {
 						Expression childExp = new Constant(Integer.toString(i), DataConstraintModel.typeInt);
-						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, 
-																							childExp, 
-																							resourceIdentifier.getResourceHierarchy().getChildren().iterator().next());
+						ResourceHierarchy childResourceHierarchy = null;
+						if (resourceIdentifier.getResourceHierarchy().getChildren() != null && resourceIdentifier.getResourceHierarchy().getChildren().size() > 0) {
+							childResourceHierarchy = resourceIdentifier.getResourceHierarchy().getChildren().iterator().next();
+						} else {
+							Type childResType = null;
+							if (listValue.get(i) instanceof Variable) {
+								childResType = ((Variable) listValue.get(i)).getType();
+							} else if (listValue.get(i) instanceof Term) {
+								childResType = ((Term) listValue.get(i)).getType();
+							}
+							childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1, childResType);
+						}
+						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, childExp, childResourceHierarchy);
 						Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, listValue.get(i));
 						state.addChildState(childInfo.getKey());
 						createInfo = new AbstractMap.SimpleEntry<>(state, childInfo.getValue());
@@ -303,9 +367,19 @@
 					if (listValue.getSymbol().equals(DataConstraintModel.append)) {
 						ListResourceState state = new ListResourceState();
 						Expression childExp = new Constant(Integer.toString(((ListResourceState) state).getChildStates().size()), DataConstraintModel.typeInt);
-						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, 
-																							childExp, 
-																							resourceIdentifier.getResourceHierarchy().getChildren().iterator().next());
+						ResourceHierarchy childResourceHierarchy = null;
+						if (resourceIdentifier.getResourceHierarchy().getChildren() != null && resourceIdentifier.getResourceHierarchy().getChildren().size() > 0) {
+							childResourceHierarchy = resourceIdentifier.getResourceHierarchy().getChildren().iterator().next();
+						} else {
+							Type childResType = null;
+							if (listValue.getChild(1) instanceof Variable) {
+								childResType = ((Variable) listValue.getChild(1)).getType();
+							} else if (listValue.getChild(1) instanceof Term) {
+								childResType = ((Term) listValue.getChild(1)).getType();
+							}
+							childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1, childResType);
+						}
+						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, childExp, childResourceHierarchy);
 						Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, listValue.getChild(1));
 						state.addChildState(childInfo.getKey());
 						return new AbstractMap.SimpleEntry<>(state, childInfo.getValue());
@@ -319,9 +393,19 @@
 					Map.Entry<ResourceState, ResourceIdentifier> createInfo = null;
 					for (String key: mapValue.keySet()) {
 						Expression childExp = new Constant(key, DataConstraintModel.typeString);
-						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, 
-																							childExp, 
-																							resourceIdentifier.getResourceHierarchy().getChildren().iterator().next());
+						ResourceHierarchy childResourceHierarchy = null;
+						if (resourceIdentifier.getResourceHierarchy().getChildren() != null && resourceIdentifier.getResourceHierarchy().getChildren().size() > 0) {
+							childResourceHierarchy = resourceIdentifier.getResourceHierarchy().getChildren().iterator().next();
+						} else {
+							Type childResType = null;
+							if (mapValue.get(key) instanceof Variable) {
+								childResType = ((Variable) mapValue.get(key)).getType();
+							} else if (mapValue.get(key) instanceof Term) {
+								childResType = ((Term) mapValue.get(key)).getType();
+							}
+							childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1, childResType);
+						}
+						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, childExp, childResourceHierarchy);
 						Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, mapValue.get(key));
 						state.addChildState(key, childInfo.getKey());
 						createInfo = new AbstractMap.SimpleEntry<>(state, childInfo.getValue());
@@ -333,9 +417,19 @@
 					Map.Entry<ResourceState, ResourceIdentifier> createInfo = null;
 					for (String key: mapValue.keySet()) {
 						Expression childExp = new Constant(key, DataConstraintModel.typeString);
-						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, 
-																							childExp, 
-																							resourceIdentifier.getResourceHierarchy().getChildren().iterator().next());
+						ResourceHierarchy childResourceHierarchy = null;
+						if (resourceIdentifier.getResourceHierarchy().getChildren() != null && resourceIdentifier.getResourceHierarchy().getChildren().size() > 0) {
+							childResourceHierarchy = resourceIdentifier.getResourceHierarchy().getChildren().iterator().next();
+						} else {
+							Type childResType = null;
+							if (mapValue.get(key) instanceof Variable) {
+								childResType = ((Variable) mapValue.get(key)).getType();
+							} else if (mapValue.get(key) instanceof Term) {
+								childResType = ((Term) mapValue.get(key)).getType();
+							}
+							childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1, childResType);
+						}
+						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, childExp, childResourceHierarchy);
 						Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, mapValue.get(key));
 						state.addChildState(key, childInfo.getKey());
 						createInfo = new AbstractMap.SimpleEntry<>(state, childInfo.getValue());
@@ -347,9 +441,19 @@
 						Expression childExp = mapValue.getChild(1);
 						if (childExp instanceof Constant) {
 							MapResourceState state = new MapResourceState();
-							ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, 
-																								childExp, 
-																								resourceIdentifier.getResourceHierarchy().getChildren().iterator().next());
+							ResourceHierarchy childResourceHierarchy = null;
+							if (resourceIdentifier.getResourceHierarchy().getChildren() != null && resourceIdentifier.getResourceHierarchy().getChildren().size() > 0) {
+								childResourceHierarchy = resourceIdentifier.getResourceHierarchy().getChildren().iterator().next();
+							} else {
+								Type childResType = null;
+								if (mapValue.getChild(2) instanceof Variable) {
+									childResType = ((Variable) mapValue.getChild(2)).getType();
+								} else if (mapValue.getChild(2) instanceof Term) {
+									childResType = ((Term) mapValue.getChild(2)).getType();
+								}
+								childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), 1, childResType);
+							}
+							ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, childExp, childResourceHierarchy);
 							String childId = ((Constant) childExp).toString();
 							Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, mapValue.getChild(2));
 							state.addChildState(childId, childInfo.getKey());
@@ -373,7 +477,13 @@
 							}
 						}
 						if (childResourceHierarchy == null) {
-							childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), memberName);
+							Type childResType = null;
+							if (jsonValue.get(key) instanceof Variable) {
+								childResType = ((Variable) jsonValue.get(key)).getType();
+							} else if (jsonValue.get(key) instanceof Term) {
+								childResType = ((Term) jsonValue.get(key)).getType();
+							}
+							childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), memberName, childResType);
 						}
 						ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, memberName, childResourceHierarchy);
 						Map.Entry<ResourceState, ResourceIdentifier> childInfo = createResourceState(childResourceIdentifier, jsonValue.get(key));
@@ -402,7 +512,13 @@
 								}
 							}
 							if (childResourceHierarchy == null) {
-								childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), memberName);
+								Type childResType = null;
+								if (jsonValue.getChild(2) instanceof Variable) {
+									childResType = ((Variable) jsonValue.getChild(2)).getType();
+								} else if (jsonValue.getChild(2) instanceof Term) {
+									childResType = ((Term) jsonValue.getChild(2)).getType();
+								}
+								childResourceHierarchy = new ResourceHierarchy(resourceIdentifier.getResourceHierarchy(), memberName, childResType);
 							}
 							ResourceIdentifier childResourceIdentifier = new ResourceIdentifier(resourceIdentifier, memberName, childResourceHierarchy);
 							String childId = ((Constant) childExp).toString();