added program and some typecheck

Source/abstractSyntaxTree/Class/FieldDecl.java

@@ -1,4 +1,23 @@
 package abstractSyntaxTree.Class;
 
+import TypeCheck.TypeCheckResult;
+
+import java.util.ArrayList;
+import java.util.List;
+
 public class FieldDecl implements IClass {
+    private String type;
+    private String identifier;
+
+    public TypeCheckResult typeCheck(List<FieldDecl> classFieldsIdentifier) throws Exception {
+        TypeCheckResult result = new TypeCheckResult();
+        if (classFieldsIdentifier.contains(this.identifier)){
+            throw new Exception("field already defined");
+        } else {
+            classFieldsIdentifier.add(this);
+        }
+        result.type = this.type;
+
+        return result;
+    }
 }

Source/abstractSyntaxTree/Class/IClass.java

@@ -1,7 +1,9 @@
 package abstractSyntaxTree.Class;
 
-public interface IClass {
-    // not type or type check
+import TypeCheck.TypeCheckResult;
 
+import java.util.List;
+
+public interface IClass {
     // visit method for code generation
 }

Source/abstractSyntaxTree/Class/MethodDecl.java

@@ -1,4 +1,12 @@
 package abstractSyntaxTree.Class;
 
+import TypeCheck.TypeCheckResult;
+
+import java.util.List;
+
 public class MethodDecl implements IClass {
+    public TypeCheckResult typeCheck(List<MethodDecl> fieldsOrMethods) throws Exception {
+        return null;
+    }
+
 }

Source/abstractSyntaxTree/Datatype/RefType.java

@@ -18,15 +18,14 @@ public class RefType extends AbstractType implements IDatatype {
     public TypeCheckResult typeCheck() throws Exception {
         TypeCheckResult result = new TypeCheckResult();
 
-//        for (FieldDecl fieldDecl : fieldDecls) {
-//            fieldDecl.typeCheck();
-//        }
-//
-//        for (MethodDecl methodDecl : methodDecls) {
-//            methodDecl.typeCheck();
-//        }
-//
-//        return result;
+        for (FieldDecl fieldDecl : fieldDecls) {
+            fieldDecl.typeCheck(fieldDecls);
+        }
+
+        for (MethodDecl methodDecl : methodDecls) {
+            methodDecl.typeCheck(methodDecls);
+        }
+
         result.type = "class";
         setTypeCheckResult(result);
         return result;

Source/abstractSyntaxTree/Program.java

@@ -0,0 +1,15 @@
+package abstractSyntaxTree;
+
+import TypeCheck.TypeCheckResult;
+import abstractSyntaxTree.Datatype.RefType;
+
+import java.util.List;
+
+public class Program {
+    public List<RefType> classes;
+
+    public TypeCheckResult typeCheck() throws Exception{
+        return null;
+    }
+
+}