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/* * $Id: PdfObject.java 3912 2009-04-26 08:38:15Z blowagie $ * * 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; /** * <CODE>PdfObject</CODE> is the abstract superclass of all PDF objects. * <P> * PDF supports seven basic types of objects: Booleans, numbers, strings, names, * arrays, dictionaries and streams. In addition, PDF provides a null object. * Objects may be labeled so that they can be referred to by other objects.<BR> * All these basic PDF objects are described in the 'Portable Document Format * Reference Manual version 1.3' Chapter 4 (pages 37-54). * * @see PdfNull * @see PdfBoolean * @see PdfNumber * @see PdfString * @see PdfName * @see PdfArray * @see PdfDictionary * @see PdfStream * @see PdfIndirectReference */ public abstract class PdfObject { // CONSTANTS /** A possible type of <CODE>PdfObject</CODE> */ public static final int BOOLEAN = 1; /** A possible type of <CODE>PdfObject</CODE> */ public static final int NUMBER = 2; /** A possible type of <CODE>PdfObject</CODE> */ public static final int STRING = 3; /** A possible type of <CODE>PdfObject</CODE> */ public static final int NAME = 4; /** A possible type of <CODE>PdfObject</CODE> */ public static final int ARRAY = 5; /** A possible type of <CODE>PdfObject</CODE> */ public static final int DICTIONARY = 6; /** A possible type of <CODE>PdfObject</CODE> */ public static final int STREAM = 7; /** A possible type of <CODE>PdfObject</CODE> */ public static final int NULL = 8; /** A possible type of <CODE>PdfObject</CODE> */ public static final int INDIRECT = 10; /** An empty string used for the <CODE>PdfNull</CODE>-object and for an empty <CODE>PdfString</CODE>-object. */ public static final String NOTHING = ""; /** * This is the default encoding to be used for converting Strings into * bytes and vice versa. The default encoding is PdfDocEncoding. */ public static final String TEXT_PDFDOCENCODING = "PDF"; /** This is the encoding to be used to output text in Unicode. */ public static final String TEXT_UNICODE = "UnicodeBig"; // CLASS VARIABLES /** The content of this <CODE>PdfObject</CODE> */ protected byte[] bytes; /** The type of this <CODE>PdfObject</CODE> */ protected int type; /** Holds the indirect reference. */ protected PRIndirectReference indRef; // CONSTRUCTORS /** * Constructs a <CODE>PdfObject</CODE> of a certain <VAR>type</VAR> * without any <VAR>content</VAR>. * * @param type type of the new <CODE>PdfObject</CODE> */ protected PdfObject(int type) { this.type = type; } /** * Constructs a <CODE>PdfObject</CODE> of a certain <VAR>type</VAR> * with a certain <VAR>content</VAR>. * * @param type type of the new <CODE>PdfObject</CODE> * @param content content of the new <CODE>PdfObject</CODE> as a * <CODE>String</CODE>. */ protected PdfObject(int type, String content) { this.type = type; bytes = PdfEncodings.convertToBytes(content, null); } /** * Constructs a <CODE>PdfObject</CODE> of a certain <VAR>type</VAR> * with a certain <VAR>content</VAR>. * * @param type type of the new <CODE>PdfObject</CODE> * @param bytes content of the new <CODE>PdfObject</CODE> as an array of * <CODE>byte</CODE>. */ protected PdfObject(int type, byte[] bytes) { this.bytes = bytes; this.type = type; } // methods dealing with the content of this object /** * Writes the PDF representation of this <CODE>PdfObject</CODE> as an * array of <CODE>byte</CODE>s to the writer. * * @param writer for backwards compatibility * @param os The <CODE>OutputStream</CODE> to write the bytes to. * @throws IOException */ public void toPdf(PdfWriter writer, OutputStream os) throws IOException { if (bytes != null) os.write(bytes); } /** * Returns the <CODE>String</CODE>-representation of this * <CODE>PdfObject</CODE>. * * @return a <CODE>String</CODE> */ public String toString() { if (bytes == null) return super.toString(); return PdfEncodings.convertToString(bytes, null); } /** * Gets the presentation of this object in a byte array * * @return a byte array */ public byte[] getBytes() { return bytes; } /** * Whether this object can be contained in an object stream. * * PdfObjects of type STREAM OR INDIRECT can not be contained in an * object stream. * * @return <CODE>true</CODE> if this object can be in an object stream. * Otherwise <CODE>false</CODE> */ public boolean canBeInObjStm() { switch (type) { case NULL: case BOOLEAN: case NUMBER: case STRING: case NAME: case ARRAY: case DICTIONARY: return true; case STREAM: case INDIRECT: default: return false; } } /** * Returns the length of the PDF representation of the <CODE>PdfObject</CODE>. * <P> * In some cases, namely for <CODE>PdfString</CODE> and <CODE>PdfStream</CODE>, * this method differs from the method <CODE>length</CODE> because <CODE>length</CODE> * returns the length of the actual content of the <CODE>PdfObject</CODE>.</P> * <P> * Remark: the actual content of an object is in most cases identical to its representation. * The following statement is always true: length() >= pdfLength().</P> * * @return a length */ // public int pdfLength() { // return toPdf(null).length; // } /** * Returns the length of the actual content of the <CODE>PdfObject</CODE>. * <P> * In some cases, namely for <CODE>PdfString</CODE> and <CODE>PdfStream</CODE>, * this method differs from the method <CODE>pdfLength</CODE> because <CODE>pdfLength</CODE> * returns the length of the PDF representation of the object, not of the actual content * as does the method <CODE>length</CODE>.</P> * <P> * Remark: the actual content of an object is in some cases identical to its representation. * The following statement is always true: length() >= pdfLength().</P> * * @return The length as <CODE>int</CODE> */ public int length() { return toString().length(); } /** * Changes the content of this <CODE>PdfObject</CODE>. * * @param content the new content of this <CODE>PdfObject</CODE> */ protected void setContent(String content) { bytes = PdfEncodings.convertToBytes(content, null); } // methods dealing with the type of this object /** * Returns the type of this <CODE>PdfObject</CODE>. * * May be either of: * - <VAR>NULL</VAR>: A <CODE>PdfNull</CODE> * - <VAR>BOOLEAN</VAR>: A <CODE>PdfBoolean</CODE> * - <VAR>NUMBER</VAR>: A <CODE>PdfNumber</CODE> * - <VAR>STRING</VAR>: A <CODE>PdfString</CODE> * - <VAR>NAME</VAR>: A <CODE>PdfName</CODE> * - <VAR>ARRAY</VAR>: A <CODE>PdfArray</CODE> * - <VAR>DICTIONARY</VAR>: A <CODE>PdfDictionary</CODE> * - <VAR>STREAM</VAR>: A <CODE>PdfStream</CODE> * - <VAR>INDIRECT</VAR>: ><CODE>PdfIndirectObject</CODE> * * @return The type */ public int type() { return type; } /** * Checks if this <CODE>PdfObject</CODE> is of the type * <CODE>PdfNull</CODE>. * * @return <CODE>true</CODE> or <CODE>false</CODE> */ public boolean isNull() { return (type == NULL); } /** * Checks if this <CODE>PdfObject</CODE> is of the type * <CODE>PdfBoolean</CODE>. * * @return <CODE>true</CODE> or <CODE>false</CODE> */ public boolean isBoolean() { return (type == BOOLEAN); } /** * Checks if this <CODE>PdfObject</CODE> is of the type * <CODE>PdfNumber</CODE>. * * @return <CODE>true</CODE> or <CODE>false</CODE> */ public boolean isNumber() { return (type == NUMBER); } /** * Checks if this <CODE>PdfObject</CODE> is of the type * <CODE>PdfString</CODE>. * * @return <CODE>true</CODE> or <CODE>false</CODE> */ public boolean isString() { return (type == STRING); } /** * Checks if this <CODE>PdfObject</CODE> is of the type * <CODE>PdfName</CODE>. * * @return <CODE>true</CODE> or <CODE>false</CODE> */ public boolean isName() { return (type == NAME); } /** * Checks if this <CODE>PdfObject</CODE> is of the type * <CODE>PdfArray</CODE>. * * @return <CODE>true</CODE> or <CODE>false</CODE> */ public boolean isArray() { return (type == ARRAY); } /** * Checks if this <CODE>PdfObject</CODE> is of the type * <CODE>PdfDictionary</CODE>. * * @return <CODE>true</CODE> or <CODE>false</CODE> */ public boolean isDictionary() { return (type == DICTIONARY); } /** * Checks if this <CODE>PdfObject</CODE> is of the type * <CODE>PdfStream</CODE>. * * @return <CODE>true</CODE> or <CODE>false</CODE> */ public boolean isStream() { return (type == STREAM); } /** * Checks if this <CODE>PdfObject</CODE> is of the type * <CODE>PdfIndirectObject</CODE>. * * @return <CODE>true</CODE> if this is an indirect object, * otherwise <CODE>false</CODE> */ public boolean isIndirect() { return (type == INDIRECT); } /** * Get the indirect reference * * @return A <CODE>PdfIndirectReference</CODE> */ public PRIndirectReference getIndRef() { return indRef; } /** * Set the indirect reference * * @param indRef New value as a <CODE>PdfIndirectReference</CODE> */ public void setIndRef(PRIndirectReference indRef) { this.indRef = indRef; } }