001/* 002 * $Id: PdfNameTree.java 4784 2011-03-15 08:33:00Z blowagie $ 003 * 004 * This file is part of the iText (R) project. 005 * Copyright (c) 1998-2011 1T3XT BVBA 006 * Authors: Bruno Lowagie, Paulo Soares, et al. 007 * 008 * This program is free software; you can redistribute it and/or modify 009 * it under the terms of the GNU Affero General Public License version 3 010 * as published by the Free Software Foundation with the addition of the 011 * following permission added to Section 15 as permitted in Section 7(a): 012 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY 1T3XT, 013 * 1T3XT DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS. 014 * 015 * This program is distributed in the hope that it will be useful, but 016 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 017 * or FITNESS FOR A PARTICULAR PURPOSE. 018 * See the GNU Affero General Public License for more details. 019 * You should have received a copy of the GNU Affero General Public License 020 * along with this program; if not, see http://www.gnu.org/licenses or write to 021 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, 022 * Boston, MA, 02110-1301 USA, or download the license from the following URL: 023 * http://itextpdf.com/terms-of-use/ 024 * 025 * The interactive user interfaces in modified source and object code versions 026 * of this program must display Appropriate Legal Notices, as required under 027 * Section 5 of the GNU Affero General Public License. 028 * 029 * In accordance with Section 7(b) of the GNU Affero General Public License, 030 * a covered work must retain the producer line in every PDF that is created 031 * or manipulated using iText. 032 * 033 * You can be released from the requirements of the license by purchasing 034 * a commercial license. Buying such a license is mandatory as soon as you 035 * develop commercial activities involving the iText software without 036 * disclosing the source code of your own applications. 037 * These activities include: offering paid services to customers as an ASP, 038 * serving PDFs on the fly in a web application, shipping iText with a closed 039 * source product. 040 * 041 * For more information, please contact iText Software Corp. at this 042 * address: sales@itextpdf.com 043 */ 044package com.itextpdf.text.pdf; 045 046import java.io.IOException; 047import java.util.Arrays; 048import java.util.HashMap; 049 050/** 051 * Creates a name tree. 052 * @author Paulo Soares 053 */ 054public class PdfNameTree { 055 056 private static final int leafSize = 64; 057 058 /** 059 * Writes a name tree to a PdfWriter. 060 * @param items the item of the name tree. The key is a <CODE>String</CODE> 061 * and the value is a <CODE>PdfObject</CODE>. Note that although the 062 * keys are strings only the lower byte is used and no check is made for chars 063 * with the same lower byte and different upper byte. This will generate a wrong 064 * tree name. 065 * @param writer the writer 066 * @throws IOException on error 067 * @return the dictionary with the name tree. This dictionary is the one 068 * generally pointed to by the key /Dests, for example 069 */ 070 public static PdfDictionary writeTree(HashMap<String, ? extends PdfObject> items, PdfWriter writer) throws IOException { 071 if (items.isEmpty()) 072 return null; 073 String names[] = new String[items.size()]; 074 names = items.keySet().toArray(names); 075 Arrays.sort(names); 076 if (names.length <= leafSize) { 077 PdfDictionary dic = new PdfDictionary(); 078 PdfArray ar = new PdfArray(); 079 for (int k = 0; k < names.length; ++k) { 080 ar.add(new PdfString(names[k], null)); 081 ar.add(items.get(names[k])); 082 } 083 dic.put(PdfName.NAMES, ar); 084 return dic; 085 } 086 int skip = leafSize; 087 PdfIndirectReference kids[] = new PdfIndirectReference[(names.length + leafSize - 1) / leafSize]; 088 for (int k = 0; k < kids.length; ++k) { 089 int offset = k * leafSize; 090 int end = Math.min(offset + leafSize, names.length); 091 PdfDictionary dic = new PdfDictionary(); 092 PdfArray arr = new PdfArray(); 093 arr.add(new PdfString(names[offset], null)); 094 arr.add(new PdfString(names[end - 1], null)); 095 dic.put(PdfName.LIMITS, arr); 096 arr = new PdfArray(); 097 for (; offset < end; ++offset) { 098 arr.add(new PdfString(names[offset], null)); 099 arr.add(items.get(names[offset])); 100 } 101 dic.put(PdfName.NAMES, arr); 102 kids[k] = writer.addToBody(dic).getIndirectReference(); 103 } 104 int top = kids.length; 105 while (true) { 106 if (top <= leafSize) { 107 PdfArray arr = new PdfArray(); 108 for (int k = 0; k < top; ++k) 109 arr.add(kids[k]); 110 PdfDictionary dic = new PdfDictionary(); 111 dic.put(PdfName.KIDS, arr); 112 return dic; 113 } 114 skip *= leafSize; 115 int tt = (names.length + skip - 1 )/ skip; 116 for (int k = 0; k < tt; ++k) { 117 int offset = k * leafSize; 118 int end = Math.min(offset + leafSize, top); 119 PdfDictionary dic = new PdfDictionary(); 120 PdfArray arr = new PdfArray(); 121 arr.add(new PdfString(names[k * skip], null)); 122 arr.add(new PdfString(names[Math.min((k + 1) * skip, names.length) - 1], null)); 123 dic.put(PdfName.LIMITS, arr); 124 arr = new PdfArray(); 125 for (; offset < end; ++offset) { 126 arr.add(kids[offset]); 127 } 128 dic.put(PdfName.KIDS, arr); 129 kids[k] = writer.addToBody(dic).getIndirectReference(); 130 } 131 top = tt; 132 } 133 } 134 135 private static void iterateItems(PdfDictionary dic, HashMap<String, PdfObject> items) { 136 PdfArray nn = (PdfArray)PdfReader.getPdfObjectRelease(dic.get(PdfName.NAMES)); 137 if (nn != null) { 138 for (int k = 0; k < nn.size(); ++k) { 139 PdfString s = (PdfString)PdfReader.getPdfObjectRelease(nn.getPdfObject(k++)); 140 items.put(PdfEncodings.convertToString(s.getBytes(), null), nn.getPdfObject(k)); 141 } 142 } 143 else if ((nn = (PdfArray)PdfReader.getPdfObjectRelease(dic.get(PdfName.KIDS))) != null) { 144 for (int k = 0; k < nn.size(); ++k) { 145 PdfDictionary kid = (PdfDictionary)PdfReader.getPdfObjectRelease(nn.getPdfObject(k)); 146 iterateItems(kid, items); 147 } 148 } 149 } 150 151 public static HashMap<String, PdfObject> readTree(PdfDictionary dic) { 152 HashMap<String, PdfObject> items = new HashMap<String, PdfObject>(); 153 if (dic != null) 154 iterateItems(dic, items); 155 return items; 156 } 157}