diff --git a/AlgebraicDataflowArchitectureModel/models/Clock.dtram b/AlgebraicDataflowArchitectureModel/models/Clock.dtram
index 380ceca..f619eaf 100644
--- a/AlgebraicDataflowArchitectureModel/models/Clock.dtram
+++ b/AlgebraicDataflowArchitectureModel/models/Clock.dtram
@@ -1,18 +1,18 @@
 model {
 channel CIO1 {
-   out min(m, tick) == mod(m + 1, 60)
+   out min(m: Int, tick) == mod(m + 1, 60)
 }
 channel HourUpdate {
-   in hour(h, update(h')) == h'
-   out hour_hand(h_ang, update(h')) == h' / 6 * PI
+   in hour(h: Int, update(h2)) == h2
+   out hour_hand(h_ang: Float, update(h2)) == h2 / 6 * PI
 }
 channel MinUpdate {
-   in min(m, update(m')) == m'
-   out min_hand(m_ang, update(m')) == m' / 30 * PI
+   in min(m, update(m2)) == m2
+   out min_hand(m_ang: Float, update(m2)) == m2 / 30 * PI
 }
 channel Clock {
-   in min(m, update(m')) == m'
-   out hour(h, update(m')) == if(eq(m', 0), mod(h + 1, 24), h)
+   in min(m, update(m2)) == m2
+   out hour(h, update(m2)) == if(eq(m2, 0), mod(h + 1, 24), h)
 }
 }
 geometry {
diff --git a/AlgebraicDataflowArchitectureModel/src/generators/CodeGenerator.java b/AlgebraicDataflowArchitectureModel/src/generators/CodeGenerator.java
index 55f1ddc..193647a 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/CodeGenerator.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/CodeGenerator.java
@@ -27,7 +27,6 @@
 import models.algebra.UnificationFailed;
 import models.algebra.ValueUndefined;
 import models.algebra.Variable;
-import models.controlFlowModel.CallEdge;
 import models.controlFlowModel.ControlFlowGraph;
 import models.controlFlowModel.EntryPointObjectNode;
 import models.controlFlowModel.ObjectNode;
@@ -549,7 +548,11 @@
 				MethodDeclaration calleeMethod = declareAndFillUpdateAndInputMethods(dstNode, outEdge, node, dataFlowInform, componentMap, langSpec);
 				if (input == null) {
 					// Declare an input method.
-					input  = langSpec.newMethodDeclaration(calleeMethod.getName(), false, null, new ArrayList<>(calleeMethod.getParameters()));
+					if (calleeMethod.getParameters() != null) {
+						input  = langSpec.newMethodDeclaration(calleeMethod.getName(), false, null, new ArrayList<>(calleeMethod.getParameters()));
+					} else {
+						input  = langSpec.newMethodDeclaration(calleeMethod.getName(), null);
+					}
 				}
 				// Add a statement to call the destination method.
 				addInvocationInMediatorUpdate(input, calleeMethod, ((ObjectNode) dstNode).getName(), dataFlowInform, langSpec);
@@ -570,7 +573,11 @@
 				MethodDeclaration calleeMethod = declareAndFillUpdateAndInputMethods(dstNode, outEdge, prevResNode, dataFlowInform, componentMap, langSpec);
 				if (updateOrInput == null && prevResNode instanceof EntryPointObjectNode) {
 					// Declare an input method.
-					updateOrInput  = langSpec.newMethodDeclaration(calleeMethod.getName(), false, null, new ArrayList<>(calleeMethod.getParameters()));
+					if (calleeMethod.getParameters() != null) {
+						updateOrInput  = langSpec.newMethodDeclaration(calleeMethod.getName(), false, null, new ArrayList<>(calleeMethod.getParameters()));
+					} else {
+						updateOrInput  = langSpec.newMethodDeclaration(calleeMethod.getName(), null);
+					}
 					component.addMethod(updateOrInput);
 				}
 				// Add a statement to call the destination method.
@@ -725,9 +732,11 @@
 	private static void addInvocationInResourceUpdate(Node node, MethodDeclaration resourceUpdateMethod, MethodDeclaration calleeMethod, String dstNodeName, ILanguageSpecific langSpec) {
 		List<String> params = new ArrayList<>();
 		params.add(langSpec.getFieldAccessor(fieldOfResourceState));
-		for (VariableDeclaration v: calleeMethod.getParameters()) {
-			if (!((ObjectNode) node).getName().equals(v.getName())) {
-				params.add(v.getName());
+		if (calleeMethod.getParameters() != null) {
+			for (VariableDeclaration v: calleeMethod.getParameters()) {
+				if (!((ObjectNode) node).getName().equals(v.getName())) {
+					params.add(v.getName());
+				}
 			}
 		}
 //		for (ChannelMember rc: re.getChannelGenerator().getReferenceChannelMembers()) {
@@ -760,8 +769,10 @@
 	private static void addInvocationInMediatorUpdate(MethodDeclaration resourceUpdateMethod, MethodDeclaration calleeMethod, String dstNodeName, Map<Edge, Map<PushPullValue,  List<ResourceNode>>> dataFlowInform, ILanguageSpecific langSpec) {
 		Map<MethodDeclaration, Set<IdentifierTemplate>> referredResources = new HashMap<>(); 
 		List<String> params = new ArrayList<>();
-		for (VariableDeclaration v: calleeMethod.getParameters()) {
-			params.add(v.getName());
+		if (calleeMethod.getParameters() != null) {
+			for (VariableDeclaration v: calleeMethod.getParameters()) {
+				params.add(v.getName());
+			}
 		}
 		resourceUpdateMethod.addStatement(langSpec.getMethodInvocation(langSpec.getFieldAccessor(dstNodeName), 
 															calleeMethod.getName(), 
@@ -1127,11 +1138,13 @@
 							mainComponent.addMethod(mainInput);
 						} else {
 							// Add type to a parameter without type.
-							for (VariableDeclaration param: mainInput.getParameters()) {
-								if (param.getType() == null) {
-									for (VariableDeclaration p: params) {
-										if (param.getName().equals(p.getName()) && p.getType() != null) {
-											param.setType(p.getType());
+							if (mainInput.getParameters() != null) {
+								for (VariableDeclaration param: mainInput.getParameters()) {
+									if (param.getType() == null) {
+										for (VariableDeclaration p: params) {
+											if (param.getName().equals(p.getName()) && p.getType() != null) {
+												param.setType(p.getType());
+											}
 										}
 									}
 								}