Shuyi Chen | d7955ce | 2013-05-22 14:51:55 -0700 | [diff] [blame] | 1 | /** |
| 2 | * $RCSfile$ |
| 3 | * $Revision$ |
| 4 | * $Date$ |
| 5 | * |
| 6 | * Copyright 2003-2007 Jive Software. |
| 7 | * |
| 8 | * All rights reserved. Licensed under the Apache License, Version 2.0 (the "License"); |
| 9 | * you may not use this file except in compliance with the License. |
| 10 | * You may obtain a copy of the License at |
| 11 | * |
| 12 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 13 | * |
| 14 | * Unless required by applicable law or agreed to in writing, software |
| 15 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 16 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 17 | * See the License for the specific language governing permissions and |
| 18 | * limitations under the License. |
| 19 | */ |
| 20 | |
| 21 | package org.jivesoftware.smack.packet; |
| 22 | |
| 23 | import java.util.*; |
| 24 | |
| 25 | /** |
| 26 | * Default implementation of the PacketExtension interface. Unless a PacketExtensionProvider |
| 27 | * is registered with {@link org.jivesoftware.smack.provider.ProviderManager ProviderManager}, |
| 28 | * instances of this class will be returned when getting packet extensions.<p> |
| 29 | * |
| 30 | * This class provides a very simple representation of an XML sub-document. Each element |
| 31 | * is a key in a Map with its CDATA being the value. For example, given the following |
| 32 | * XML sub-document: |
| 33 | * |
| 34 | * <pre> |
| 35 | * <foo xmlns="http://bar.com"> |
| 36 | * <color>blue</color> |
| 37 | * <food>pizza</food> |
| 38 | * </foo></pre> |
| 39 | * |
| 40 | * In this case, getValue("color") would return "blue", and getValue("food") would |
| 41 | * return "pizza". This parsing mechanism mechanism is very simplistic and will not work |
| 42 | * as desired in all cases (for example, if some of the elements have attributes. In those |
| 43 | * cases, a custom PacketExtensionProvider should be used. |
| 44 | * |
| 45 | * @author Matt Tucker |
| 46 | */ |
| 47 | public class DefaultPacketExtension implements PacketExtension { |
| 48 | |
| 49 | private String elementName; |
| 50 | private String namespace; |
| 51 | private Map<String,String> map; |
| 52 | |
| 53 | /** |
| 54 | * Creates a new generic packet extension. |
| 55 | * |
| 56 | * @param elementName the name of the element of the XML sub-document. |
| 57 | * @param namespace the namespace of the element. |
| 58 | */ |
| 59 | public DefaultPacketExtension(String elementName, String namespace) { |
| 60 | this.elementName = elementName; |
| 61 | this.namespace = namespace; |
| 62 | } |
| 63 | |
| 64 | /** |
| 65 | * Returns the XML element name of the extension sub-packet root element. |
| 66 | * |
| 67 | * @return the XML element name of the packet extension. |
| 68 | */ |
| 69 | public String getElementName() { |
| 70 | return elementName; |
| 71 | } |
| 72 | |
| 73 | /** |
| 74 | * Returns the XML namespace of the extension sub-packet root element. |
| 75 | * |
| 76 | * @return the XML namespace of the packet extension. |
| 77 | */ |
| 78 | public String getNamespace() { |
| 79 | return namespace; |
| 80 | } |
| 81 | |
| 82 | public String toXML() { |
| 83 | StringBuilder buf = new StringBuilder(); |
| 84 | buf.append("<").append(elementName).append(" xmlns=\"").append(namespace).append("\">"); |
| 85 | for (String name : getNames()) { |
| 86 | String value = getValue(name); |
| 87 | buf.append("<").append(name).append(">"); |
| 88 | buf.append(value); |
| 89 | buf.append("</").append(name).append(">"); |
| 90 | } |
| 91 | buf.append("</").append(elementName).append(">"); |
| 92 | return buf.toString(); |
| 93 | } |
| 94 | |
| 95 | /** |
| 96 | * Returns an unmodifiable collection of the names that can be used to get |
| 97 | * values of the packet extension. |
| 98 | * |
| 99 | * @return the names. |
| 100 | */ |
| 101 | public synchronized Collection<String> getNames() { |
| 102 | if (map == null) { |
| 103 | return Collections.emptySet(); |
| 104 | } |
| 105 | return Collections.unmodifiableSet(new HashMap<String,String>(map).keySet()); |
| 106 | } |
| 107 | |
| 108 | /** |
| 109 | * Returns a packet extension value given a name. |
| 110 | * |
| 111 | * @param name the name. |
| 112 | * @return the value. |
| 113 | */ |
| 114 | public synchronized String getValue(String name) { |
| 115 | if (map == null) { |
| 116 | return null; |
| 117 | } |
| 118 | return map.get(name); |
| 119 | } |
| 120 | |
| 121 | /** |
| 122 | * Sets a packet extension value using the given name. |
| 123 | * |
| 124 | * @param name the name. |
| 125 | * @param value the value. |
| 126 | */ |
| 127 | public synchronized void setValue(String name, String value) { |
| 128 | if (map == null) { |
| 129 | map = new HashMap<String,String>(); |
| 130 | } |
| 131 | map.put(name, value); |
| 132 | } |
| 133 | } |