diff --git a/AlgebraicDataflowArchitectureModel/src/generators/JavaImplementationVisitor.java b/AlgebraicDataflowArchitectureModel/src/generators/JavaImplementationVisitor.java
index 3b1d8ce..c9e1ced 100644
--- a/AlgebraicDataflowArchitectureModel/src/generators/JavaImplementationVisitor.java
+++ b/AlgebraicDataflowArchitectureModel/src/generators/JavaImplementationVisitor.java
@@ -5,6 +5,8 @@
 import models.dataConstraintModel.JsonAccessor;
 import models.dataConstraintModel.JsonTerm;
 
+import java.util.List;
+
 /**
  * This class is a Java implementation of {@link IExpressionVisitor}
  * which holds and manages the actual method of implementation code generation
@@ -15,7 +17,7 @@
 	private static int jsonCount = 0;
 	
 	@Override
-	public String visit(Term term, String[] sideEffects) {
+	public code.ast.Expression visit(Term term, String[] sideEffects) {
 		int[] implParamOrder = term.getSymbol().getImplParamOrder();
 		if (term.getSymbol().isImplLambda()) {
 			String[] components = term.getSymbol().getImplName().split("->");
@@ -152,39 +154,51 @@
 	}
 	
 	@Override
-	public String visit(Field field, String[] sideEffects) {
-		return "this." + visit((Constant) field, sideEffects);
+	public code.ast.Expression visit(Field field, String[] sideEffects) {
+		return new code.ast.FieldAccess(new code.ast.ThisExpression(), visit((Constant) field, sideEffects).toString());
 	}
 	
 	@Override
-	public String visit(Constant constant, String[] sideEffects) {
+	public code.ast.Expression visit(Constant constant, String[] sideEffects) {
 		if (constant.getSymbol().isImplGenerative()) {
 			String exp = constant.getSymbol().generate(constant.getType(), new Type[]{}, new String[]{}, new String[]{}, sideEffects);
 			return exp;
 		}
-		return constant.getSymbol().getImplName();
+		
+		return new code.ast.Constant(constant.getSymbol().getImplName());
 	}
 	
 	@Override
-	public String visit(Variable variable, String[] sideEffects) {
-		return variable.getName();
+	public code.ast.Expression visit(Variable variable, String[] sideEffects) {
+		return new code.ast.Variable(variable.getName());
 	}
 	
 	@Override
-	public String visit(JsonTerm jsonTerm, String[] sideEffects) {
+	public code.ast.Expression visit(JsonTerm jsonTerm, String[] sideEffects) {
 		String temp = "temp_json" + jsonCount;
 		jsonCount++;
+		
+		code.ast.Type mapType = new code.ast.SimpleType("Map");
+		code.ast.Type stringType = new code.ast.SimpleType("String");
+		code.ast.Type objectType = new code.ast.SimpleType("Object");
+		
+		code.ast.Type type = new code.ast.ParameterizedType(mapType, List.of(stringType, objectType));
+		code.ast.VariableDeclaration fragment = new code.ast.VariableDeclaration(new Type("Map", type.toString()), temp);
+		
+		// TODO: Implement this correctly
+		
 		String impl = "";
 		impl += "Map<String, Object> " + temp + " = new HashMap<>();\n";
 		for (String key : jsonTerm.keySet()) {
 			impl += temp + ".put(\"" + key + "\", " + jsonTerm.get(key).accept(this, sideEffects) + ");\n";
 		}
 		sideEffects[0] += impl;
+		
 		return temp;
 	}
 	
 	@Override
-	public String visit(JsonAccessor jsonAccessor, String[] sideEffects) {
+	public code.ast.Expression visit(JsonAccessor jsonAccessor, String[] sideEffects) {
 		if (jsonAccessor.getSymbol().equals(DataConstraintModel.dotParam)) {
 			return jsonAccessor.getChildren().get(0).accept(this, sideEffects) + "." + jsonAccessor.getSymbol().toImplementation() + "(" + jsonAccessor.getChildren().get(1).accept(this, sideEffects) + ")";
 		}
diff --git a/AlgebraicDataflowArchitectureModel/src/models/algebra/Constant.java b/AlgebraicDataflowArchitectureModel/src/models/algebra/Constant.java
index 2b0e579..78f1b37 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/algebra/Constant.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/algebra/Constant.java
@@ -44,11 +44,11 @@
 	}
 	
 	public String toImplementation(String[] sideEffects) {
-		return accept(new JavaImplementationVisitor(), sideEffects);
+		return accept(new JavaImplementationVisitor(), sideEffects).toString();
 	}
 	
 	@Override
-	public String accept(IExpressionVisitor visitor, String[] sideEffects) {
+	public code.ast.Expression accept(IExpressionVisitor visitor, String[] sideEffects) {
 		return visitor.visit(this, sideEffects);
 	}
 }
diff --git a/AlgebraicDataflowArchitectureModel/src/models/algebra/Expression.java b/AlgebraicDataflowArchitectureModel/src/models/algebra/Expression.java
index 65345a1..1f79f27 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/algebra/Expression.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/algebra/Expression.java
@@ -32,7 +32,7 @@
 		return getSubTerms(Variable.class);
 	}
 	
-	public abstract String accept(IExpressionVisitor visitor, String[] sideEffects);
+	public abstract code.ast.Expression accept(IExpressionVisitor visitor, String[] sideEffects);
 	
 	/**
 	 * Get the implementation of this expression.
diff --git a/AlgebraicDataflowArchitectureModel/src/models/algebra/Field.java b/AlgebraicDataflowArchitectureModel/src/models/algebra/Field.java
index 93076df..73fd891 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/algebra/Field.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/algebra/Field.java
@@ -42,11 +42,11 @@
 	}
 	
 	public String toImplementation(String[] sideEffects) {
-		return accept(new JavaImplementationVisitor(), sideEffects);
+		return accept(new JavaImplementationVisitor(), sideEffects).toString();
 	}
 	
 	@Override
-	public String accept(IExpressionVisitor visitor, String[] sideEffects) {
+	public code.ast.Expression accept(IExpressionVisitor visitor, String[] sideEffects) {
 		return visitor.visit(this, sideEffects);
 	}
 }
diff --git a/AlgebraicDataflowArchitectureModel/src/models/algebra/IExpressionVisitor.java b/AlgebraicDataflowArchitectureModel/src/models/algebra/IExpressionVisitor.java
index a8a88f5..29e5c2a 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/algebra/IExpressionVisitor.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/algebra/IExpressionVisitor.java
@@ -4,15 +4,15 @@
 import models.dataConstraintModel.JsonTerm;
 
 public interface IExpressionVisitor {
-	String visit(Term term, String[] sideEffects);
+	code.ast.Expression visit(Term term, String[] sideEffects);
 	
-	String visit(Field field, String[] sideEffects);
+	code.ast.Expression visit(Field field, String[] sideEffects);
 	
-	String visit(Constant constant, String[] sideEffects);
+	code.ast.Expression visit(Constant constant, String[] sideEffects);
 	
-	String visit(Variable variable, String[] sideEffects);
+	code.ast.Expression visit(Variable variable, String[] sideEffects);
 	
-	String visit(JsonTerm jsonTerm, String[] sideEffects);
+	code.ast.Expression visit(JsonTerm jsonTerm, String[] sideEffects);
 	
-	String visit(JsonAccessor jsonAccessor, String[] sideEffects);
+	code.ast.Expression visit(JsonAccessor jsonAccessor, String[] sideEffects);
 }
diff --git a/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java b/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java
index 72f71a8..32f97c4 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/algebra/Term.java
@@ -312,11 +312,11 @@
 	}
 	
 	public String toImplementation(String[] sideEffects) {
-		return accept(new JavaImplementationVisitor(), sideEffects);
+		return accept(new JavaImplementationVisitor(), sideEffects).toString();
 	}
 	
 	@Override
-	public String accept(IExpressionVisitor visitor, String[] sideEffects) {
+	public code.ast.Expression accept(IExpressionVisitor visitor, String[] sideEffects) {
 		return visitor.visit(this, sideEffects);
 	}
 }
diff --git a/AlgebraicDataflowArchitectureModel/src/models/algebra/Variable.java b/AlgebraicDataflowArchitectureModel/src/models/algebra/Variable.java
index 336a87f..eca4319 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/algebra/Variable.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/algebra/Variable.java
@@ -84,11 +84,11 @@
 	}
 	
 	public String toImplementation(String[] sideEffects) {
-		return accept(new JavaImplementationVisitor(), sideEffects);
+		return accept(new JavaImplementationVisitor(), sideEffects).toString();
 	}
 	
 	@Override
-	public String accept(IExpressionVisitor visitor, String[] sideEffects) {
+	public code.ast.Expression accept(IExpressionVisitor visitor, String[] sideEffects) {
 		return visitor.visit(this, sideEffects);
 	}
 }
diff --git a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/JsonAccessor.java b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/JsonAccessor.java
index 1cf0c22..de7eb5b 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/JsonAccessor.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/JsonAccessor.java
@@ -205,11 +205,11 @@
 	}
 	
 	public String toImplementation(String[] sideEffects) {
-		return accept(new JavaImplementationVisitor(), sideEffects);
+		return accept(new JavaImplementationVisitor(), sideEffects).toString();
 	}
 	
 	@Override
-	public String accept(IExpressionVisitor visitor, String[] sideEffects) {
+	public code.ast.Expression accept(IExpressionVisitor visitor, String[] sideEffects) {
 		return visitor.visit(this, sideEffects);
 	}
 	
diff --git a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/JsonTerm.java b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/JsonTerm.java
index 608a27e..26d796a 100644
--- a/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/JsonTerm.java
+++ b/AlgebraicDataflowArchitectureModel/src/models/dataConstraintModel/JsonTerm.java
@@ -91,11 +91,11 @@
 	}
 	
 	public String toImplementation(String[] sideEffects) {
-		return accept(new JavaImplementationVisitor(), sideEffects);
+		return accept(new JavaImplementationVisitor(), sideEffects).toString();
 	}
 	
 	@Override
-	public String accept(IExpressionVisitor visitor, String[] sideEffects) {
+	public code.ast.Expression accept(IExpressionVisitor visitor, String[] sideEffects) {
 		return visitor.visit(this, sideEffects);
 	}
 }