/**
 * @license
 * Copyright 2017 The FOAM Authors. All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

foam.CLASS({
  package: 'foam.box',
  name: 'Message',

  properties: [
    {
      class: 'Map',
      name: 'attributes'
    },
    {
      class: 'Object',
      name: 'object'
    },
    {
      class: 'Map',
      transient: true,
      name: 'localAttributes'
    }
  ]
});

@@ -747,24 +747,78 @@
 'attributes'
+,%0A      javaFactory: 'return new java.util.HashMap();'
 %0A    %7D,%0A    
@@ -948,16 +948,70 @@
 ributes'
+,%0A      javaFactory: 'return new java.util.HashMap();'
 %0A    %7D%0A 

Add java factories for Message.attributes/localAttributes to improve usability.