/*
* $Id: TreeNodeFactory.java 4242 2010-01-02 23:22:20Z xlv $
*
* Copyright 2007 Bruno Lowagie.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/
package com.itextpdf.rups.model;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;
import com.itextpdf.rups.view.itext.treenodes.PdfObjectTreeNode;
import com.itextpdf.rups.view.itext.treenodes.PdfPagesTreeNode;
import com.itextpdf.text.pdf.PdfArray;
import com.itextpdf.text.pdf.PdfDictionary;
import com.itextpdf.text.pdf.PdfIndirectReference;
import com.itextpdf.text.pdf.PdfName;
import com.itextpdf.text.pdf.PdfNull;
import com.itextpdf.text.pdf.PdfObject;
/**
* A factory that creates TreeNode objects corresponding with PDF objects.
*/
public class TreeNodeFactory {
/** The factory that can produce all indirect objects. */
protected IndirectObjectFactory objects;
/** An list containing the nodes of every indirect object. */
protected ArrayList<PdfObjectTreeNode> nodes = new ArrayList<PdfObjectTreeNode>();
/**
* Creates a factory that can produce TreeNode objects
* corresponding with PDF objects.
* @param objects a factory that can produce all the indirect objects of a PDF file.
*/
public TreeNodeFactory(IndirectObjectFactory objects) {
this.objects = objects;
for (int i = 0; i < objects.size(); i++) {
int ref = objects.getRefByIndex(i);
nodes.add(PdfObjectTreeNode.getInstance(PdfNull.PDFNULL, ref));
}
}
/**
* Gets a TreeNode for an indirect objects.
* @param ref the reference number of the indirect object.
* @return the TreeNode representing the PDF object
*/
public PdfObjectTreeNode getNode(int ref) {
int idx = objects.getIndexByRef(ref);
PdfObjectTreeNode node = nodes.get(idx);
if (node.getPdfObject().isNull()) {
node = PdfObjectTreeNode.getInstance(objects.loadObjectByReference(ref), ref);
nodes.set(idx, node);
}
return node;
}
/**
* Creates the Child TreeNode objects for a PDF object TreeNode.
* @param node the parent node
*/
public void expandNode(PdfObjectTreeNode node) {
if (node.getChildCount() > 0) {
return;
}
PdfObject object = node.getPdfObject();
PdfObjectTreeNode leaf;
switch (object.type()) {
case PdfObject.INDIRECT:
PdfIndirectReference ref = (PdfIndirectReference)object;
leaf = getNode(ref.getNumber());
addNodes(node, leaf);
if (leaf instanceof PdfPagesTreeNode)
expandNode(leaf);
return;
case PdfObject.ARRAY:
PdfArray array = (PdfArray)object;
for (Iterator<PdfObject> it = array.listIterator(); it.hasNext(); ) {
leaf = PdfObjectTreeNode.getInstance(it.next());
addNodes(node, leaf);
expandNode(leaf);
}
return;
case PdfObject.DICTIONARY:
case PdfObject.STREAM:
PdfDictionary dict = (PdfDictionary)object;
for (PdfName element : dict.getKeys()) {
leaf = PdfObjectTreeNode.getInstance(dict, element);
addNodes(node, leaf);
expandNode(leaf);
}
return;
}
}
/**
* Finds a specific child of dictionary node.
* @param node the node with a dictionary among its children
* @param key the key of the item corresponding with the node we need
*/
@SuppressWarnings("unchecked")
public PdfObjectTreeNode getChildNode(PdfObjectTreeNode node, PdfName key) {
Enumeration<PdfObjectTreeNode> children = node.breadthFirstEnumeration();
PdfObjectTreeNode child;
while (children.hasMoreElements()) {
child = children.nextElement();
if (child.isDictionaryNode(key)) {
if (child.isIndirectReference()) {
expandNode(child);
child = (PdfObjectTreeNode)child.getFirstChild();
}
expandNode(child);
return child;
}
}
return null;
}
/**
* Tries adding a child node to a parent node without
* throwing an exception. Normally, if the child node is already
* added as one of the ancestors, an IllegalArgumentException is
* thrown (to avoid an endless loop). Loops like this are allowed
* in PDF, not in a JTree.
* @param parent the parent node
* @param child a child node
*/
private void addNodes(PdfObjectTreeNode parent, PdfObjectTreeNode child) {
try {
parent.add(child);
}
catch(IllegalArgumentException iae) {
parent.setRecursive(true);
}
}
}