diff --git a/src/main/java/org/ntlab/rdlworkbench/models/RDLSpec.java b/src/main/java/org/ntlab/rdlworkbench/models/RDLSpec.java
index d3496e0..89a2ac1 100644
--- a/src/main/java/org/ntlab/rdlworkbench/models/RDLSpec.java
+++ b/src/main/java/org/ntlab/rdlworkbench/models/RDLSpec.java
@@ -3,10 +3,15 @@
 import java.util.*;
 
 public class RDLSpec {
-    Map<String, RDLSpecResourceDeclaration> resourceMap = new TreeMap<>();
-    List<RDLSpecStatement> rdlSpecStatements = new ArrayList<>();
+    private Map<String, RDLSpecResourceDeclaration> resourceMap;
+    private List<RDLSpecStatement> rdlSpecStatements;
 
-    public void putResourceMap(String name, int order, StructuralType structuralType, ValueType valueType) {
+    public RDLSpec() {
+        resourceMap = new HashMap<>();
+        rdlSpecStatements = new ArrayList<>();
+    }
+
+    public void putRDLSpecResourceDeclaration(String name, int order, StructuralType structuralType, ValueType valueType) {
         resourceMap.put(name, new RDLSpecResourceDeclaration(name, order, structuralType, valueType));
     }
 
@@ -30,6 +35,10 @@
         }));
     }
 
+    public List<RDLSpecStatement> getRDLSpecStatements() {
+        return rdlSpecStatements;
+    }
+
     @Override
     public String toString() {
         StringBuilder sb = new StringBuilder();
diff --git a/src/main/java/org/ntlab/rdlworkbench/rdlparser/RDLParser.java b/src/main/java/org/ntlab/rdlworkbench/rdlparser/RDLParser.java
index 3c13192..2e0ce42 100644
--- a/src/main/java/org/ntlab/rdlworkbench/rdlparser/RDLParser.java
+++ b/src/main/java/org/ntlab/rdlworkbench/rdlparser/RDLParser.java
@@ -342,11 +342,11 @@
             String structuralType = tokenStream.next();
             expect(COMMA);
             String valueType = tokenStream.next();
-            rdlSpec.putResourceMap(resourceName, order, StructuralType.id, new ValueType(valueType));
+            rdlSpec.putRDLSpecResourceDeclaration(resourceName, order, StructuralType.id, new ValueType(valueType));
             return rdlSpec.getRDLSpecResourceDeclaration(resourceName);
         } else if (tokenStream.checkNext().equals("struct")) {
             String structuralType = tokenStream.next();
-            rdlSpec.putResourceMap(resourceName, order, StructuralType.structure, null);
+            rdlSpec.putRDLSpecResourceDeclaration(resourceName, order, StructuralType.structure, null);
             return rdlSpec.getRDLSpecResourceDeclaration(resourceName);
         } else {
             String structuralType = "primitive";
@@ -356,7 +356,7 @@
                 throw new NullPointerException("need valueType");
             }
 
-            rdlSpec.putResourceMap(resourceName, order, StructuralType.primitive, new ValueType(valueType));
+            rdlSpec.putRDLSpecResourceDeclaration(resourceName, order, StructuralType.primitive, new ValueType(valueType));
             return rdlSpec.getRDLSpecResourceDeclaration(resourceName);
         }
     }