1 /*
   2  * $Id$
   3  *
   4  * Copyright (c) 2004, 2009, Oracle and/or its affiliates. All rights reserved.
   5  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   6  *
   7  * This code is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License version 2 only, as
   9  * published by the Free Software Foundation.  Oracle designates this
  10  * particular file as subject to the "Classpath" exception as provided
  11  * by Oracle in the LICENSE file that accompanied this code.
  12  *
  13  * This code is distributed in the hope that it will be useful, but WITHOUT
  14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16  * version 2 for more details (a copy is included in the LICENSE file that
  17  * accompanied this code).
  18  *
  19  * You should have received a copy of the GNU General Public License version
  20  * 2 along with this work; if not, write to the Free Software Foundation,
  21  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  22  *
  23  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  24  * or visit www.oracle.com if you need additional information or have any
  25  * questions.
  26  */
  27 package com.sun.javatest.util;
  28 
  29 import java.util.Enumeration;
  30 import java.util.Iterator;
  31 import java.util.Properties;
  32 import java.util.Set;
  33 import java.util.TreeSet;
  34 
  35 /**
  36  * A subtype of Properties for which the keys method will return a sorted enumeration.
  37  * This means that the store method will write the various properties in sorted order.
  38  */
  39 public class SortedProperties extends Properties
  40 {
  41     // override Keys() to return a sorted set
  42     public Enumeration<Object> keys() {
  43         Set<Object> s = new TreeSet<>(); // ordered
  44         for (Enumeration e = super.keys(); e.hasMoreElements(); ) {
  45             s.add(e.nextElement());
  46         }
  47 
  48         final Iterator iter = s.iterator();
  49         return new Enumeration<Object>() {
  50                 public boolean hasMoreElements() {
  51                     return iter.hasNext();
  52                 }
  53                 public Object nextElement() {
  54                     return iter.next();
  55                 }
  56             };
  57     }
  58 }