/*
* Copyright 2005 by Paulo Soares.
*
* The contents of this file are subject to the Mozilla Public License Version 1.1
* (the "License"); you may not use this file except in compliance with the License.
* You may obtain a copy of the License at http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the License.
*
* The Original Code is 'iText, a free JAVA-PDF library'.
*
* The Initial Developer of the Original Code is Bruno Lowagie. Portions created by
* the Initial Developer are Copyright (C) 1999, 2000, 2001, 2002 by Bruno Lowagie.
* All Rights Reserved.
* Co-Developer of the code is Paulo Soares. Portions created by the Co-Developer
* are Copyright (C) 2000, 2001, 2002 by Paulo Soares. All Rights Reserved.
*
* Contributor(s): all the names of the contributors are added in the source code
* where applicable.
*
* Alternatively, the contents of this file may be used under the terms of the
* LGPL license (the "GNU LIBRARY GENERAL PUBLIC LICENSE"), in which case the
* provisions of LGPL are applicable instead of those above. If you wish to
* allow use of your version of this file only under the terms of the LGPL
* License and not to allow others to use your version of this file under
* the MPL, indicate your decision by deleting the provisions above and
* replace them with the notice and other provisions required by the LGPL.
* If you do not delete the provisions above, a recipient may use your version
* of this file under either the MPL or the GNU LIBRARY GENERAL PUBLIC LICENSE.
*
* This library is free software; you can redistribute it and/or modify it
* under the terms of the MPL as stated above or under the terms of the GNU
* Library General Public License as published by the Free Software Foundation;
* either version 2 of the License, or 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 Library general Public License for more
* details.
*
* If you didn't download this code from the following link, you should check if
* you aren't using an obsolete version:
* http://www.lowagie.com/iText/
*/
package com.lowagie.text.pdf;
import java.io.IOException;
import java.util.Arrays;
import java.util.HashMap;
/**
* Creates a number tree.
* @author Paulo Soares (psoares@consiste.pt)
*/
public class PdfNumberTree {
private static final int leafSize = 64;
/**
* Creates a number tree.
* @param items the item of the number tree. The key is an <CODE>Integer</CODE>
* and the value is a <CODE>PdfObject</CODE>.
* @param writer the writer
* @throws IOException on error
* @return the dictionary with the number tree.
*/
public static PdfDictionary writeTree(HashMap items, PdfWriter writer) throws IOException {
if (items.isEmpty())
return null;
Integer numbers[] = new Integer[items.size()];
numbers = (Integer[])items.keySet().toArray(numbers);
Arrays.sort(numbers);
if (numbers.length <= leafSize) {
PdfDictionary dic = new PdfDictionary();
PdfArray ar = new PdfArray();
for (int k = 0; k < numbers.length; ++k) {
ar.add(new PdfNumber(numbers[k].intValue()));
ar.add((PdfObject)items.get(numbers[k]));
}
dic.put(PdfName.NUMS, ar);
return dic;
}
int skip = leafSize;
PdfIndirectReference kids[] = new PdfIndirectReference[(numbers.length + leafSize - 1) / leafSize];
for (int k = 0; k < kids.length; ++k) {
int offset = k * leafSize;
int end = Math.min(offset + leafSize, numbers.length);
PdfDictionary dic = new PdfDictionary();
PdfArray arr = new PdfArray();
arr.add(new PdfNumber(numbers[offset].intValue()));
arr.add(new PdfNumber(numbers[end - 1].intValue()));
dic.put(PdfName.LIMITS, arr);
arr = new PdfArray();
for (; offset < end; ++offset) {
arr.add(new PdfNumber(numbers[offset].intValue()));
arr.add((PdfObject)items.get(numbers[offset]));
}
dic.put(PdfName.NUMS, arr);
kids[k] = writer.addToBody(dic).getIndirectReference();
}
int top = kids.length;
while (true) {
if (top <= leafSize) {
PdfArray arr = new PdfArray();
for (int k = 0; k < top; ++k)
arr.add(kids[k]);
PdfDictionary dic = new PdfDictionary();
dic.put(PdfName.KIDS, arr);
return dic;
}
skip *= leafSize;
int tt = (numbers.length + skip - 1 )/ skip;
for (int k = 0; k < tt; ++k) {
int offset = k * leafSize;
int end = Math.min(offset + leafSize, top);
PdfDictionary dic = new PdfDictionary();
PdfArray arr = new PdfArray();
arr.add(new PdfNumber(numbers[k * skip].intValue()));
arr.add(new PdfNumber(numbers[Math.min((k + 1) * skip, numbers.length) - 1].intValue()));
dic.put(PdfName.LIMITS, arr);
arr = new PdfArray();
for (; offset < end; ++offset) {
arr.add(kids[offset]);
}
dic.put(PdfName.KIDS, arr);
kids[k] = writer.addToBody(dic).getIndirectReference();
}
top = tt;
}
}
private static void iterateItems(PdfDictionary dic, HashMap items) {
PdfArray nn = (PdfArray)PdfReader.getPdfObjectRelease(dic.get(PdfName.NUMS));
if (nn != null) {
for (int k = 0; k < nn.size(); ++k) {
PdfNumber s = (PdfNumber)PdfReader.getPdfObjectRelease(nn.getPdfObject(k++));
items.put(new Integer(s.intValue()), nn.getPdfObject(k));
}
}
else if ((nn = (PdfArray)PdfReader.getPdfObjectRelease(dic.get(PdfName.KIDS))) != null) {
for (int k = 0; k < nn.size(); ++k) {
PdfDictionary kid = (PdfDictionary)PdfReader.getPdfObjectRelease(nn.getPdfObject(k));
iterateItems(kid, items);
}
}
}
public static HashMap readTree(PdfDictionary dic) {
HashMap items = new HashMap();
if (dic != null)
iterateItems(dic, items);
return items;
}
}