001// Copyright 2004, 2005 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.hivemind.impl;
016
017import java.util.ArrayList;
018import java.util.Collections;
019import java.util.HashMap;
020import java.util.List;
021import java.util.Map;
022
023import org.apache.hivemind.Attribute;
024import org.apache.hivemind.Element;
025import org.apache.hivemind.util.ToStringBuilder;
026
027/**
028 * Implementation of {@link org.apache.hivemind.Element}.
029 *
030 * @author Howard Lewis Ship
031 */
032public final class ElementImpl extends BaseLocatable implements Element
033{
034    private String _elementName;
035    private String _content;
036    private List _elements;
037    private List _safeElements;
038    private List _attributes;
039    private Map _attributesMap;
040    private List _safeAttributes;
041
042    public void setElementName(String elementName)
043    {
044        _elementName = elementName;
045    }
046
047    public String getElementName()
048    {
049        return _elementName;
050    }
051
052    public void addAttribute(Attribute attribute)
053    {
054        if (_attributes == null)
055        {
056            _attributes = new ArrayList();
057            _attributesMap = new HashMap();
058        }
059
060        _attributes.add(attribute);
061        _attributesMap.put(attribute.getName(), attribute);
062    }
063
064    public void addElement(Element element)
065    {
066        if (_elements == null)
067            _elements = new ArrayList();
068
069        _elements.add(element);
070    }
071
072    public synchronized List getAttributes()
073    {
074        if (_attributes == null)
075            return Collections.EMPTY_LIST;
076
077        if (_safeAttributes == null)
078            _safeAttributes = Collections.unmodifiableList(_attributes);
079
080        return _safeAttributes;
081    }
082
083    public String getContent()
084    {
085        if (_content == null)
086            return "";
087
088        return _content;
089    }
090
091    public synchronized List getElements()
092    {
093        if (_elements == null)
094            return Collections.EMPTY_LIST;
095
096        if (_safeElements == null)
097            _safeElements = Collections.unmodifiableList(_elements);
098
099        return _safeElements;
100    }
101
102    public String getAttributeValue(String attributeName)
103    {
104        if (_attributesMap == null)
105            return null;
106
107        Attribute a = (Attribute) _attributesMap.get(attributeName);
108
109        if (a == null)
110            return null;
111
112        return a.getValue();
113    }
114
115    public boolean isEmpty()
116    {
117        return _elements == null || _elements.size() == 0;
118    }
119
120    public void setContent(String string)
121    {
122        _content = string;
123    }
124
125    public String toString()
126    {
127        ToStringBuilder builder = new ToStringBuilder(this);
128
129        builder.append("elementName", _elementName);
130        builder.append("attributes", _attributes);
131        builder.append("elements", _elements);
132        builder.append("content", _content);
133
134        return builder.toString();
135    }
136}