1 /*
2  * $Id$
3  *
4  * Copyright 2007 Bruno Lowagie.
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
19  */
20 
21 package com.lowagie.rups.model;
22 
23 import java.util.ArrayList;
24 import java.util.Enumeration;
25 import java.util.Iterator;
26 
27 import com.lowagie.rups.view.itext.treenodes.PdfObjectTreeNode;
28 import com.lowagie.rups.view.itext.treenodes.PdfPagesTreeNode;
29 import com.lowagie.text.pdf.PdfArray;
30 import com.lowagie.text.pdf.PdfDictionary;
31 import com.lowagie.text.pdf.PdfIndirectReference;
32 import com.lowagie.text.pdf.PdfName;
33 import com.lowagie.text.pdf.PdfNull;
34 import com.lowagie.text.pdf.PdfObject;
35 
36 /**
37  * A factory that creates TreeNode objects corresponding with PDF objects.
38  */
39 public class TreeNodeFactory {
40 
41 	/** The factory that can produce all indirect objects. */
42 	protected IndirectObjectFactory objects;
43 	/** An list containing the nodes of every indirect object. */
44 	protected ArrayList<PdfObjectTreeNode> nodes = new ArrayList<PdfObjectTreeNode>();
45 
46 	/**
47 	 * Creates a factory that can produce TreeNode objects
48 	 * corresponding with PDF objects.
49 	 * @param objects	a factory that can produce all the indirect objects of a PDF file.
50 	 */
TreeNodeFactory(IndirectObjectFactory objects)51 	public TreeNodeFactory(IndirectObjectFactory objects) {
52 		this.objects = objects;
53 		for (int i = 0; i < objects.size(); i++) {
54 			int ref = objects.getRefByIndex(i);
55 			nodes.add(PdfObjectTreeNode.getInstance(PdfNull.PDFNULL, ref));
56 		}
57 	}
58 
59 	/**
60 	 * Gets a TreeNode for an indirect objects.
61 	 * @param ref	the reference number of the indirect object.
62 	 * @return	the TreeNode representing the PDF object
63 	 */
getNode(int ref)64 	public PdfObjectTreeNode getNode(int ref) {
65 		int idx = objects.getIndexByRef(ref);
66 		PdfObjectTreeNode node = nodes.get(idx);
67 		if (node.getPdfObject().isNull()) {
68 			node = PdfObjectTreeNode.getInstance(objects.loadObjectByReference(ref), ref);
69 			nodes.set(idx, node);
70 		}
71 		return node;
72 	}
73 
74 	/**
75 	 * Creates the Child TreeNode objects for a PDF object TreeNode.
76 	 * @param node	the parent node
77 	 */
expandNode(PdfObjectTreeNode node)78 	public void expandNode(PdfObjectTreeNode node) {
79 		if (node.getChildCount() > 0) {
80 			return;
81 		}
82 		PdfObject object = node.getPdfObject();
83 		PdfObjectTreeNode leaf;
84 		switch (object.type()) {
85 		case PdfObject.INDIRECT:
86 			PdfIndirectReference ref = (PdfIndirectReference)object;
87 			leaf = getNode(ref.getNumber());
88 			addNodes(node, leaf);
89 			if (leaf instanceof PdfPagesTreeNode)
90 				expandNode(leaf);
91 			return;
92 		case PdfObject.ARRAY:
93 			PdfArray array = (PdfArray)object;
94 			for (Iterator it = array.listIterator(); it.hasNext(); ) {
95 				leaf = PdfObjectTreeNode.getInstance((PdfObject)it.next());
96 				addNodes(node, leaf);
97 				expandNode(leaf);
98 			}
99 			return;
100 		case PdfObject.DICTIONARY:
101 		case PdfObject.STREAM:
102 			PdfDictionary dict = (PdfDictionary)object;
103 			for (Iterator it = dict.getKeys().iterator(); it.hasNext(); ) {
104 				leaf = PdfObjectTreeNode.getInstance(dict, (PdfName)it.next());
105 				addNodes(node, leaf);
106 				expandNode(leaf);
107 			}
108 			return;
109 		}
110 	}
111 
112 	/**
113 	 * Finds a specific child of dictionary node.
114 	 * @param	node	the node with a dictionary among its children
115 	 * @param	key		the key of the item corresponding with the node we need
116 	 */
getChildNode(PdfObjectTreeNode node, PdfName key)117 	public PdfObjectTreeNode getChildNode(PdfObjectTreeNode node, PdfName key) {
118 		Enumeration children = node.breadthFirstEnumeration();
119 		PdfObjectTreeNode child;
120 		while (children.hasMoreElements()) {
121 			child = (PdfObjectTreeNode)children.nextElement();
122 			if (child.isDictionaryNode(key)) {
123 				if (child.isIndirectReference()) {
124 					expandNode(child);
125 					child = (PdfObjectTreeNode)child.getFirstChild();
126 				}
127 				expandNode(child);
128 				return child;
129 			}
130 		}
131 		return null;
132 	}
133 
134 	/**
135 	 * Tries adding a child node to a parent node without
136 	 * throwing an exception. Normally, if the child node is already
137 	 * added as one of the ancestors, an IllegalArgumentException is
138 	 * thrown (to avoid an endless loop). Loops like this are allowed
139 	 * in PDF, not in a JTree.
140 	 * @param parent	the parent node
141 	 * @param child		a child node
142 	 */
addNodes(PdfObjectTreeNode parent, PdfObjectTreeNode child)143 	private void addNodes(PdfObjectTreeNode parent, PdfObjectTreeNode child) {
144 		try {
145 			parent.add(child);
146 		}
147 		catch(IllegalArgumentException iae) {
148 			parent.setRecursive(true);
149 		}
150 	}
151 }
152