Java tutorial
/* * Copyright 2004 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 name tree. * @author Paulo Soares (psoares@consiste.pt) */ public class PdfNameTree { private static final int leafSize = 64; /** * Writes a name tree to a PdfWriter. * @param items the item of the name tree. The key is a <CODE>String</CODE> * and the value is a <CODE>PdfObject</CODE>. Note that although the * keys are strings only the lower byte is used and no check is made for chars * with the same lower byte and different upper byte. This will generate a wrong * tree name. * @param writer the writer * @throws IOException on error * @return the dictionary with the name tree. This dictionary is the one * generally pointed to by the key /Dests, for example */ public static PdfDictionary writeTree(HashMap items, PdfWriter writer) throws IOException { if (items.isEmpty()) return null; String names[] = new String[items.size()]; names = (String[]) items.keySet().toArray(names); Arrays.sort(names); if (names.length <= leafSize) { PdfDictionary dic = new PdfDictionary(); PdfArray ar = new PdfArray(); for (int k = 0; k < names.length; ++k) { ar.add(new PdfString(names[k], null)); ar.add((PdfObject) items.get(names[k])); } dic.put(PdfName.NAMES, ar); return dic; } int skip = leafSize; PdfIndirectReference kids[] = new PdfIndirectReference[(names.length + leafSize - 1) / leafSize]; for (int k = 0; k < kids.length; ++k) { int offset = k * leafSize; int end = Math.min(offset + leafSize, names.length); PdfDictionary dic = new PdfDictionary(); PdfArray arr = new PdfArray(); arr.add(new PdfString(names[offset], null)); arr.add(new PdfString(names[end - 1], null)); dic.put(PdfName.LIMITS, arr); arr = new PdfArray(); for (; offset < end; ++offset) { arr.add(new PdfString(names[offset], null)); arr.add((PdfObject) items.get(names[offset])); } dic.put(PdfName.NAMES, 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 = (names.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 PdfString(names[k * skip], null)); arr.add(new PdfString(names[Math.min((k + 1) * skip, names.length) - 1], null)); 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.NAMES)); if (nn != null) { for (int k = 0; k < nn.size(); ++k) { PdfString s = (PdfString) PdfReader.getPdfObjectRelease(nn.getPdfObject(k++)); items.put(PdfEncodings.convertToString(s.getBytes(), null), 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; } }