1 /*
2 * $Id: PdfIndirectObject.java 3912 2009-04-26 08:38:15Z blowagie $
3 * $Name$
4 *
5 * Copyright 1999, 2000, 2001, 2002 Bruno Lowagie
6 *
7 * The contents of this file are subject to the Mozilla Public License Version 1.1
8 * (the "License"); you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at http://www.mozilla.org/MPL/
10 *
11 * Software distributed under the License is distributed on an "AS IS" basis,
12 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
13 * for the specific language governing rights and limitations under the License.
14 *
15 * The Original Code is 'iText, a free JAVA-PDF library'.
16 *
17 * The Initial Developer of the Original Code is Bruno Lowagie. Portions created by
18 * the Initial Developer are Copyright (C) 1999, 2000, 2001, 2002 by Bruno Lowagie.
19 * All Rights Reserved.
20 * Co-Developer of the code is Paulo Soares. Portions created by the Co-Developer
21 * are Copyright (C) 2000, 2001, 2002 by Paulo Soares. All Rights Reserved.
22 *
23 * Contributor(s): all the names of the contributors are added in the source code
24 * where applicable.
25 *
26 * Alternatively, the contents of this file may be used under the terms of the
27 * LGPL license (the "GNU LIBRARY GENERAL PUBLIC LICENSE"), in which case the
28 * provisions of LGPL are applicable instead of those above. If you wish to
29 * allow use of your version of this file only under the terms of the LGPL
30 * License and not to allow others to use your version of this file under
31 * the MPL, indicate your decision by deleting the provisions above and
32 * replace them with the notice and other provisions required by the LGPL.
33 * If you do not delete the provisions above, a recipient may use your version
34 * of this file under either the MPL or the GNU LIBRARY GENERAL PUBLIC LICENSE.
35 *
36 * This library is free software; you can redistribute it and/or modify it
37 * under the terms of the MPL as stated above or under the terms of the GNU
38 * Library General Public License as published by the Free Software Foundation;
39 * either version 2 of the License, or any later version.
40 *
41 * This library is distributed in the hope that it will be useful, but WITHOUT
42 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
43 * FOR A PARTICULAR PURPOSE. See the GNU Library general Public License for more
44 * details.
45 *
46 * If you didn't download this code from the following link, you should check if
47 * you aren't using an obsolete version:
48 * http://www.lowagie.com/iText/
49 */
50
51 package com.lowagie.text.pdf;
52
53 import java.io.IOException;
54 import java.io.OutputStream;
55
56 import com.lowagie.text.DocWriter;
57
58 /**
59 * <CODE>PdfIndirectObject</CODE> is the Pdf indirect object.
60 * <P>
61 * An <I>indirect object</I> is an object that has been labeled so that it can be referenced by
62 * other objects. Any type of <CODE>PdfObject</CODE> may be labeled as an indirect object.<BR>
63 * An indirect object consists of an object identifier, a direct object, and the <B>endobj</B>
64 * keyword. The <I>object identifier</I> consists of an integer <I>object number</I>, an integer
65 * <I>generation number</I>, and the <B>obj</B> keyword.<BR>
66 * This object is described in the 'Portable Document Format Reference Manual version 1.7'
67 * section 3.2.9 (page 63-65).
68 *
69 * @see PdfObject
70 * @see PdfIndirectReference
71 */
72
73 public class PdfIndirectObject {
74
75 // membervariables
76
77 /** The object number */
78 protected int number;
79
80 /** the generation number */
81 protected int generation = 0;
82
83 static final byte STARTOBJ[] = DocWriter.getISOBytes(" obj\n");
84 static final byte ENDOBJ[] = DocWriter.getISOBytes("\nendobj\n");
85 static final int SIZEOBJ = STARTOBJ.length + ENDOBJ.length;
86 PdfObject object;
87 PdfWriter writer;
88
89 // constructors
90
91 /**
92 * Constructs a <CODE>PdfIndirectObject</CODE>.
93 *
94 * @param number the object number
95 * @param object the direct object
96 */
97
98 PdfIndirectObject(int number, PdfObject object, PdfWriter writer) {
99 this(number, 0, object, writer);
100 }
101
102 PdfIndirectObject(PdfIndirectReference ref, PdfObject object, PdfWriter writer) {
103 this(ref.getNumber(),ref.getGeneration(),object,writer);
104 }
105 /**
106 * Constructs a <CODE>PdfIndirectObject</CODE>.
107 *
108 * @param number the object number
109 * @param generation the generation number
110 * @param object the direct object
111 */
112
113 PdfIndirectObject(int number, int generation, PdfObject object, PdfWriter writer) {
114 this.writer = writer;
115 this.number = number;
116 this.generation = generation;
117 this.object = object;
118 PdfEncryption crypto = null;
119 if (writer != null)
120 crypto = writer.getEncryption();
121 if (crypto != null) {
122 crypto.setHashKey(number, generation);
123 }
124 }
125
126 // methods
127
128 /**
129 * Return the length of this <CODE>PdfIndirectObject</CODE>.
130 *
131 * @return the length of the PDF-representation of this indirect object.
132 */
133
134 // public int length() {
135 // if (isStream)
136 // return bytes.size() + SIZEOBJ + stream.getStreamLength(writer);
137 // else
138 // return bytes.size();
139 // }
140
141
142 /**
143 * Returns a <CODE>PdfIndirectReference</CODE> to this <CODE>PdfIndirectObject</CODE>.
144 *
145 * @return a <CODE>PdfIndirectReference</CODE>
146 */
147
148 public PdfIndirectReference getIndirectReference() {
149 return new PdfIndirectReference(object.type(), number, generation);
150 }
151
152 /**
153 * Writes efficiently to a stream
154 *
155 * @param os the stream to write to
156 * @throws IOException on write error
157 */
158 void writeTo(OutputStream os) throws IOException
159 {
160 os.write(DocWriter.getISOBytes(String.valueOf(number)));
161 os.write(' ');
162 os.write(DocWriter.getISOBytes(String.valueOf(generation)));
163 os.write(STARTOBJ);
164 object.toPdf(writer, os);
165 os.write(ENDOBJ);
166 }
167 }
168