add isSubTypeOf(9 to the type hierarchy

src/de/inetsoftware/jwebassembly/wasm/AnyType.java

@@ -15,6 +15,8 @@
  */
 package de.inetsoftware.jwebassembly.wasm;
 
+import javax.annotation.Nonnull;
+
 /**
  * Interface of all possible types in WebAssembly. This are predefined (native) types and custom types in the type section.
  * <pre><code>
@@ -36,4 +38,13 @@ public interface AnyType {
      * @return the code
      */
     public int getCode();
+
+    /**
+     * Check if this is a sub type of given type.
+     * 
+     * @param type
+     *            type to check
+     * @return true, if both are identical or the type is a sub type
+     */
+    public boolean isSubTypeOf( @Nonnull AnyType type );
 }

src/de/inetsoftware/jwebassembly/wasm/ArrayType.java

@@ -50,6 +50,14 @@ public class ArrayType implements AnyType {
         return ValueType.anyref.getCode();
     }
 
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public boolean isSubTypeOf( AnyType type ) {
+        return type == this || type == ValueType.anyref;
+    }
+
     /**
      * {@inheritDoc}
      */

src/de/inetsoftware/jwebassembly/wasm/ValueType.java

@@ -57,4 +57,12 @@ public enum ValueType implements AnyType {
     public int getCode() {
         return code;
     }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public boolean isSubTypeOf( AnyType type ) {
+        return type == this;
+    }
 }