/*
*
* This file is part of the iText (R) project.
Copyright (c) 1998-2017 iText Group NV
* Authors: Bruno Lowagie, Paulo Soares, et al.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License version 3
* as published by the Free Software Foundation with the addition of the
* following permission added to Section 15 as permitted in Section 7(a):
* FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
* ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
* OF THIRD PARTY RIGHTS
*
* This program 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 Affero General Public License for more details.
* You should have received a copy of the GNU Affero General Public License
* along with this program; if not, see http://www.gnu.org/licenses or write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA, 02110-1301 USA, or download the license from the following URL:
* http://itextpdf.com/terms-of-use/
*
* The interactive user interfaces in modified source and object code versions
* of this program must display Appropriate Legal Notices, as required under
* Section 5 of the GNU Affero General Public License.
*
* In accordance with Section 7(b) of the GNU Affero General Public License,
* a covered work must retain the producer line in every PDF that is created
* or manipulated using iText.
*
* You can be released from the requirements of the license by purchasing
* a commercial license. Buying such a license is mandatory as soon as you
* develop commercial activities involving the iText software without
* disclosing the source code of your own applications.
* These activities include: offering paid services to customers as an ASP,
* serving PDFs on the fly in a web application, shipping iText with a closed
* source product.
*
* For more information, please contact iText Software Corp. at this
* address: sales@itextpdf.com
*/
package com.itextpdf.text.pdf;
import java.io.IOException;
import java.util.Arrays;
import java.util.HashMap;
/**
* Creates a name tree.
* @author Paulo Soares
*/
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<String, ? extends PdfObject> items, PdfWriter writer) throws IOException {
if (items.isEmpty())
return null;
String names[] = new String[items.size()];
names = 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(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(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 PdfString iterateItems(PdfDictionary dic, HashMap<String, PdfObject> items, PdfString leftOverString) {
PdfArray nn = (PdfArray)PdfReader.getPdfObjectRelease(dic.get(PdfName.NAMES));
if (nn != null) {
for (int k = 0; k < nn.size(); ++k) {
PdfString s;
if (leftOverString == null)
s = (PdfString)PdfReader.getPdfObjectRelease(nn.getPdfObject(k++));
else {
// this is the leftover string from the previous loop
s = leftOverString;
leftOverString = null;
}
if (k < nn.size()) // could have a mistake int the pdf file
items.put(PdfEncodings.convertToString(s.getBytes(), null), nn.getPdfObject(k));
else
return s;
}
} 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));
leftOverString = iterateItems(kid, items, leftOverString);
}
}
return null;
}
public static HashMap<String, PdfObject> readTree(PdfDictionary dic) {
HashMap<String, PdfObject> items = new HashMap<String, PdfObject>();
if (dic != null)
iterateItems(dic, items, null);
return items;
}
}