Source Code Cross Referenced for DeepNodeListImpl.java in  » XML » xerces-2_9_1 » org » apache » xerces » dom » Java Source Code / Java DocumentationJava Source Code and Java Documentation

Java Source Code / Java Documentation
1. 6.0 JDK Core
2. 6.0 JDK Modules
3. 6.0 JDK Modules com.sun
4. 6.0 JDK Modules com.sun.java
5. 6.0 JDK Modules sun
6. 6.0 JDK Platform
7. Ajax
8. Apache Harmony Java SE
9. Aspect oriented
10. Authentication Authorization
11. Blogger System
12. Build
13. Byte Code
14. Cache
15. Chart
16. Chat
17. Code Analyzer
18. Collaboration
19. Content Management System
20. Database Client
21. Database DBMS
22. Database JDBC Connection Pool
23. Database ORM
24. Development
25. EJB Server geronimo
26. EJB Server GlassFish
27. EJB Server JBoss 4.2.1
28. EJB Server resin 3.1.5
29. ERP CRM Financial
30. ESB
31. Forum
32. GIS
33. Graphic Library
34. Groupware
35. HTML Parser
36. IDE
37. IDE Eclipse
38. IDE Netbeans
39. Installer
40. Internationalization Localization
41. Inversion of Control
42. Issue Tracking
43. J2EE
44. JBoss
45. JMS
46. JMX
47. Library
48. Mail Clients
49. Net
50. Parser
51. PDF
52. Portal
53. Profiler
54. Project Management
55. Report
56. RSS RDF
57. Rule Engine
58. Science
59. Scripting
60. Search Engine
61. Security
62. Sevlet Container
63. Source Control
64. Swing Library
65. Template Engine
66. Test Coverage
67. Testing
68. UML
69. Web Crawler
70. Web Framework
71. Web Mail
72. Web Server
73. Web Services
74. Web Services apache cxf 2.0.1
75. Web Services AXIS2
76. Wiki Engine
77. Workflow Engines
78. XML
79. XML UI
Java
Java Tutorial
Java Open Source
Jar File Download
Java Articles
Java Products
Java by API
Photoshop Tutorials
Maya Tutorials
Flash Tutorials
3ds-Max Tutorials
Illustrator Tutorials
GIMP Tutorials
C# / C Sharp
C# / CSharp Tutorial
C# / CSharp Open Source
ASP.Net
ASP.NET Tutorial
JavaScript DHTML
JavaScript Tutorial
JavaScript Reference
HTML / CSS
HTML CSS Reference
C / ANSI-C
C Tutorial
C++
C++ Tutorial
Ruby
PHP
Python
Python Tutorial
Python Open Source
SQL Server / T-SQL
SQL Server / T-SQL Tutorial
Oracle PL / SQL
Oracle PL/SQL Tutorial
PostgreSQL
SQL / MySQL
MySQL Tutorial
VB.Net
VB.Net Tutorial
Flash / Flex / ActionScript
VBA / Excel / Access / Word
XML
XML Tutorial
Microsoft Office PowerPoint 2007 Tutorial
Microsoft Office Excel 2007 Tutorial
Microsoft Office Word 2007 Tutorial
Java Source Code / Java Documentation » XML » xerces 2_9_1 » org.apache.xerces.dom 
Source Cross Referenced  Class Diagram Java Document (Java Doc) 


001:        /*
002:         * Licensed to the Apache Software Foundation (ASF) under one or more
003:         * contributor license agreements.  See the NOTICE file distributed with
004:         * this work for additional information regarding copyright ownership.
005:         * The ASF licenses this file to You under the Apache License, Version 2.0
006:         * (the "License"); you may not use this file except in compliance with
007:         * the License.  You may obtain a copy of the License at
008:         * 
009:         *      http://www.apache.org/licenses/LICENSE-2.0
010:         * 
011:         * Unless required by applicable law or agreed to in writing, software
012:         * distributed under the License is distributed on an "AS IS" BASIS,
013:         * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014:         * See the License for the specific language governing permissions and
015:         * limitations under the License.
016:         */
017:
018:        package org.apache.xerces.dom;
019:
020:        import org.w3c.dom.Node;
021:        import org.w3c.dom.NodeList;
022:
023:        import java.util.Vector;
024:
025:        /**
026:         * This class implements the DOM's NodeList behavior for
027:         * Element.getElementsByTagName()
028:         * <P>
029:         * The DOM describes NodeList as follows:
030:         * <P>
031:         * 1) It may represent EITHER nodes scattered through a subtree (when
032:         * returned by Element.getElementsByTagName), or just the immediate
033:         * children (when returned by Node.getChildNodes). The latter is easy,
034:         * but the former (which this class addresses) is more challenging.
035:         * <P>
036:         * 2) Its behavior is "live" -- that is, it always reflects the
037:         * current state of the document tree. To put it another way, the
038:         * NodeLists obtained before and after a series of insertions and
039:         * deletions are effectively identical (as far as the user is
040:         * concerned, the former has been dynamically updated as the changes
041:         * have been made).
042:         * <P>
043:         * 3) Its API accesses individual nodes via an integer index, with the
044:         * listed nodes numbered sequentially in the order that they were
045:         * found during a preorder depth-first left-to-right search of the tree.
046:         * (Of course in the case of getChildNodes, depth is not involved.) As
047:         * nodes are inserted or deleted in the tree, and hence the NodeList,
048:         * the numbering of nodes that follow them in the NodeList will
049:         * change.
050:         * <P>
051:         * It is rather painful to support the latter two in the
052:         * getElementsByTagName case. The current solution is for Nodes to
053:         * maintain a change count (eventually that may be a Digest instead),
054:         * which the NodeList tracks and uses to invalidate itself.
055:         * <P>
056:         * Unfortunately, this does _not_ respond efficiently in the case that
057:         * the dynamic behavior was supposed to address: scanning a tree while
058:         * it is being extended. That requires knowing which subtrees have
059:         * changed, which can become an arbitrarily complex problem.
060:         * <P>
061:         * We save some work by filling the vector only as we access the
062:         * item()s... but I suspect the same users who demanded index-based
063:         * access will also start by doing a getLength() to control their loop,
064:         * blowing this optimization out of the water.
065:         * <P>
066:         * NOTE: Level 2 of the DOM will probably _not_ use NodeList for its
067:         * extended search mechanisms, partly for the reasons just discussed.
068:         * 
069:         * @xerces.internal
070:         *
071:         * @version $Id: DeepNodeListImpl.java 447266 2006-09-18 05:57:49Z mrglavas $
072:         * @since  PR-DOM-Level-1-19980818.
073:         */
074:        public class DeepNodeListImpl implements  NodeList {
075:
076:            //
077:            // Data
078:            //
079:
080:            protected NodeImpl rootNode; // Where the search started
081:            protected String tagName; // Or "*" to mean all-tags-acceptable
082:            protected int changes = 0;
083:            protected Vector nodes;
084:
085:            protected String nsName;
086:            protected boolean enableNS = false;
087:
088:            //
089:            // Constructors
090:            //
091:
092:            /** Constructor. */
093:            public DeepNodeListImpl(NodeImpl rootNode, String tagName) {
094:                this .rootNode = rootNode;
095:                this .tagName = tagName;
096:                nodes = new Vector();
097:            }
098:
099:            /** Constructor for Namespace support. */
100:            public DeepNodeListImpl(NodeImpl rootNode, String nsName,
101:                    String tagName) {
102:                this (rootNode, tagName);
103:                this .nsName = (nsName != null && !nsName.equals("")) ? nsName
104:                        : null;
105:                enableNS = true;
106:            }
107:
108:            //
109:            // NodeList methods
110:            //
111:
112:            /** Returns the length of the node list. */
113:            public int getLength() {
114:                // Preload all matching elements. (Stops when we run out of subtree!)
115:                item(java.lang.Integer.MAX_VALUE);
116:                return nodes.size();
117:            }
118:
119:            /** Returns the node at the specified index. */
120:            public Node item(int index) {
121:                Node this Node;
122:
123:                // Tree changed. Do it all from scratch!
124:                if (rootNode.changes() != changes) {
125:                    nodes = new Vector();
126:                    changes = rootNode.changes();
127:                }
128:
129:                // In the cache
130:                if (index < nodes.size())
131:                    return (Node) nodes.elementAt(index);
132:
133:                // Not yet seen
134:                else {
135:
136:                    // Pick up where we left off (Which may be the beginning)
137:                    if (nodes.size() == 0)
138:                        this Node = rootNode;
139:                    else
140:                        this Node = (NodeImpl) (nodes.lastElement());
141:
142:                    // Add nodes up to the one we're looking for
143:                    while (this Node != null && index >= nodes.size()) {
144:                        this Node = nextMatchingElementAfter(this Node);
145:                        if (this Node != null)
146:                            nodes.addElement(this Node);
147:                    }
148:
149:                    // Either what we want, or null (not avail.)
150:                    return this Node;
151:                }
152:
153:            } // item(int):Node
154:
155:            //
156:            // Protected methods (might be overridden by an extending DOM)
157:            //
158:
159:            /** 
160:             * Iterative tree-walker. When you have a Parent link, there's often no
161:             * need to resort to recursion. NOTE THAT only Element nodes are matched
162:             * since we're specifically supporting getElementsByTagName().
163:             */
164:            protected Node nextMatchingElementAfter(Node current) {
165:
166:                Node next;
167:                while (current != null) {
168:                    // Look down to first child.
169:                    if (current.hasChildNodes()) {
170:                        current = (current.getFirstChild());
171:                    }
172:
173:                    // Look right to sibling (but not from root!)
174:                    else if (current != rootNode
175:                            && null != (next = current.getNextSibling())) {
176:                        current = next;
177:                    }
178:
179:                    // Look up and right (but not past root!)
180:                    else {
181:                        next = null;
182:                        for (; current != rootNode; // Stop when we return to starting point
183:                        current = current.getParentNode()) {
184:
185:                            next = current.getNextSibling();
186:                            if (next != null)
187:                                break;
188:                        }
189:                        current = next;
190:                    }
191:
192:                    // Have we found an Element with the right tagName?
193:                    // ("*" matches anything.)
194:                    if (current != rootNode && current != null
195:                            && current.getNodeType() == Node.ELEMENT_NODE) {
196:                        if (!enableNS) {
197:                            if (tagName.equals("*")
198:                                    || ((ElementImpl) current).getTagName()
199:                                            .equals(tagName)) {
200:                                return current;
201:                            }
202:                        } else {
203:                            // DOM2: Namespace logic. 
204:                            if (tagName.equals("*")) {
205:                                if (nsName != null && nsName.equals("*")) {
206:                                    return current;
207:                                } else {
208:                                    ElementImpl el = (ElementImpl) current;
209:                                    if ((nsName == null && el.getNamespaceURI() == null)
210:                                            || (nsName != null && nsName
211:                                                    .equals(el
212:                                                            .getNamespaceURI()))) {
213:                                        return current;
214:                                    }
215:                                }
216:                            } else {
217:                                ElementImpl el = (ElementImpl) current;
218:                                if (el.getLocalName() != null
219:                                        && el.getLocalName().equals(tagName)) {
220:                                    if (nsName != null && nsName.equals("*")) {
221:                                        return current;
222:                                    } else {
223:                                        if ((nsName == null && el
224:                                                .getNamespaceURI() == null)
225:                                                || (nsName != null && nsName
226:                                                        .equals(el
227:                                                                .getNamespaceURI()))) {
228:                                            return current;
229:                                        }
230:                                    }
231:                                }
232:                            }
233:                        }
234:                    }
235:
236:                    // Otherwise continue walking the tree
237:                }
238:
239:                // Fell out of tree-walk; no more instances found
240:                return null;
241:
242:            } // nextMatchingElementAfter(int):Node
243:
244:        } // class DeepNodeListImpl
www.java2java.com | Contact Us
Copyright 2009 - 12 Demo Source and Support. All rights reserved.
All other trademarks are property of their respective owners.