Updating to work with java 1.6

Author: sk02241994

src/main/java/org/json/JSONObject.java

@@ -3526,11 +3526,12 @@ public Map create() {
     /**
      * Converts a String to an Enum value.
      */
-    private <E extends Enum<E>> E stringToEnum(Class<?> enumClass, String value) throws JSONException {
+    private <E> E stringToEnum(Class<?> enumClass, String value) throws JSONException {
         try {
             @SuppressWarnings("unchecked")
             Class<E> enumType = (Class<E>) enumClass;
-            return Enum.valueOf(enumType, value);
+            Method valueOfMethod = enumType.getMethod("valueOf", String.class);
+            return (E) valueOfMethod.invoke(null, value);
         } catch (Exception e) {
             throw new JSONException("Failed to convert string to enum: " + value + " for " + enumClass.getName(), e);
         }