1 /*
   2  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package com.sun.xml.internal.bind.v2.runtime.unmarshaller;
  27 
  28 import org.xml.sax.SAXException;
  29 
  30 /**
  31  * Decorates another {@link Loader} by setting a default value.
  32  *
  33  * @author Kohsuke Kawaguchi
  34  */
  35 public final class DefaultValueLoaderDecorator extends Loader {
  36     private final Loader l;
  37     private final String defaultValue;
  38 
  39     public DefaultValueLoaderDecorator(Loader l, String defaultValue) {
  40         this.l = l;
  41         this.defaultValue = defaultValue;
  42     }
  43 
  44     @Override
  45     public void startElement(UnmarshallingContext.State state, TagName ea) throws SAXException {
  46         // install the default value, but don't override the one given by the parent loader
  47         if(state.getElementDefaultValue() == null)
  48             state.setElementDefaultValue(defaultValue);
  49 
  50         state.setLoader(l);
  51         l.startElement(state,ea);
  52     }
  53 }