Java tutorial
/* * $Id: PdfIndirectObject.java 3912 2009-04-26 08:38:15Z blowagie $ * $Name$ * * Copyright 1999, 2000, 2001, 2002 Bruno Lowagie * * 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.io.OutputStream; import com.lowagie.text.DocWriter; /** * <CODE>PdfIndirectObject</CODE> is the Pdf indirect object. * <P> * An <I>indirect object</I> is an object that has been labeled so that it can be referenced by * other objects. Any type of <CODE>PdfObject</CODE> may be labeled as an indirect object.<BR> * An indirect object consists of an object identifier, a direct object, and the <B>endobj</B> * keyword. The <I>object identifier</I> consists of an integer <I>object number</I>, an integer * <I>generation number</I>, and the <B>obj</B> keyword.<BR> * This object is described in the 'Portable Document Format Reference Manual version 1.7' * section 3.2.9 (page 63-65). * * @see PdfObject * @see PdfIndirectReference */ public class PdfIndirectObject { // membervariables /** The object number */ protected int number; /** the generation number */ protected int generation = 0; static final byte STARTOBJ[] = DocWriter.getISOBytes(" obj\n"); static final byte ENDOBJ[] = DocWriter.getISOBytes("\nendobj\n"); static final int SIZEOBJ = STARTOBJ.length + ENDOBJ.length; PdfObject object; PdfWriter writer; // constructors /** * Constructs a <CODE>PdfIndirectObject</CODE>. * * @param number the object number * @param object the direct object */ PdfIndirectObject(int number, PdfObject object, PdfWriter writer) { this(number, 0, object, writer); } PdfIndirectObject(PdfIndirectReference ref, PdfObject object, PdfWriter writer) { this(ref.getNumber(), ref.getGeneration(), object, writer); } /** * Constructs a <CODE>PdfIndirectObject</CODE>. * * @param number the object number * @param generation the generation number * @param object the direct object */ PdfIndirectObject(int number, int generation, PdfObject object, PdfWriter writer) { this.writer = writer; this.number = number; this.generation = generation; this.object = object; PdfEncryption crypto = null; if (writer != null) crypto = writer.getEncryption(); if (crypto != null) { crypto.setHashKey(number, generation); } } // methods /** * Return the length of this <CODE>PdfIndirectObject</CODE>. * * @return the length of the PDF-representation of this indirect object. */ // public int length() { // if (isStream) // return bytes.size() + SIZEOBJ + stream.getStreamLength(writer); // else // return bytes.size(); // } /** * Returns a <CODE>PdfIndirectReference</CODE> to this <CODE>PdfIndirectObject</CODE>. * * @return a <CODE>PdfIndirectReference</CODE> */ public PdfIndirectReference getIndirectReference() { return new PdfIndirectReference(object.type(), number, generation); } /** * Writes efficiently to a stream * * @param os the stream to write to * @throws IOException on write error */ void writeTo(OutputStream os) throws IOException { os.write(DocWriter.getISOBytes(String.valueOf(number))); os.write(' '); os.write(DocWriter.getISOBytes(String.valueOf(generation))); os.write(STARTOBJ); object.toPdf(writer, os); os.write(ENDOBJ); } }