com.lowagie.text.pdf.PdfObject Maven / Gradle / Ivy
/*
* $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:
* https://github.com/LibrePDF/OpenPDF
*/
package com.lowagie.text.pdf;
import java.io.IOException;
import java.io.OutputStream;
/**
* PdfObject is the abstract superclass of all PDF objects.
*
* 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.
* 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 PdfObject */
public static final int BOOLEAN = 1;
/** A possible type of PdfObject */
public static final int NUMBER = 2;
/** A possible type of PdfObject */
public static final int STRING = 3;
/** A possible type of PdfObject */
public static final int NAME = 4;
/** A possible type of PdfObject */
public static final int ARRAY = 5;
/** A possible type of PdfObject */
public static final int DICTIONARY = 6;
/** A possible type of PdfObject */
public static final int STREAM = 7;
/** A possible type of PdfObject */
public static final int NULL = 8;
/** A possible type of PdfObject */
public static final int INDIRECT = 10;
/** An empty string used for the PdfNull-object and for an empty PdfString-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 PdfObject */
protected byte[] bytes;
/** The type of this PdfObject */
protected int type;
/** Holds the indirect reference. */
protected PRIndirectReference indRef;
// CONSTRUCTORS
/**
* Constructs a PdfObject of a certain type
* without any content.
*
* @param type type of the new PdfObject
*/
protected PdfObject(int type) {
this.type = type;
}
/**
* Constructs a PdfObject of a certain type
* with a certain content.
*
* @param type type of the new PdfObject
* @param content content of the new PdfObject as a
* String.
*/
protected PdfObject(int type, String content) {
this.type = type;
bytes = PdfEncodings.convertToBytes(content, null);
}
/**
* Constructs a PdfObject of a certain type
* with a certain content.
*
* @param type type of the new PdfObject
* @param bytes content of the new PdfObject as an array of
* byte.
*/
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 PdfObject as an
* array of bytes to the writer.
*
* @param writer for backwards compatibility
* @param os The OutputStream to write the bytes to.
* @throws IOException on error
*/
public void toPdf(PdfWriter writer, OutputStream os) throws IOException {
if (bytes != null)
os.write(bytes);
}
/**
* Returns the String-representation of this
* PdfObject.
*
* @return a String
*/
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 true if this object can be in an object stream.
* Otherwise false
*/
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 PdfObject.
*
* In some cases, namely for PdfString and PdfStream,
* this method differs from the method length because length
* returns the length of the actual content of the PdfObject.
*
* Remark: the actual content of an object is in most cases identical to its representation.
* The following statement is always true: length() >= pdfLength().
*
* @return a length
*/
// public int pdfLength() {
// return toPdf(null).length;
// }
/**
* Returns the length of the actual content of the PdfObject.
*
* In some cases, namely for PdfString and PdfStream,
* this method differs from the method pdfLength because pdfLength
* returns the length of the PDF representation of the object, not of the actual content
* as does the method length.
*
* Remark: the actual content of an object is in some cases identical to its representation.
* The following statement is always true: length() >= pdfLength().
*
* @return The length as int
*/
public int length() {
return toString().length();
}
/**
* Changes the content of this PdfObject.
*
* @param content the new content of this PdfObject
*/
protected void setContent(String content) {
bytes = PdfEncodings.convertToBytes(content, null);
}
// methods dealing with the type of this object
/**
* Returns the type of this PdfObject.
*
* May be either of:
* - NULL: A PdfNull
* - BOOLEAN: A PdfBoolean
* - NUMBER: A PdfNumber
* - STRING: A PdfString
* - NAME: A PdfName
* - ARRAY: A PdfArray
* - DICTIONARY: A PdfDictionary
* - STREAM: A PdfStream
* - INDIRECT: {@literal >} PdfIndirectObject
*
* @return The type
*/
public int type() {
return type;
}
/**
* Checks if this PdfObject is of the type
* PdfNull.
*
* @return true or false
*/
public boolean isNull() {
return (type == NULL);
}
/**
* Checks if this PdfObject is of the type
* PdfBoolean.
*
* @return true or false
*/
public boolean isBoolean() {
return (type == BOOLEAN);
}
/**
* Checks if this PdfObject is of the type
* PdfNumber.
*
* @return true or false
*/
public boolean isNumber() {
return (type == NUMBER);
}
/**
* Checks if this PdfObject is of the type
* PdfString.
*
* @return true or false
*/
public boolean isString() {
return (type == STRING);
}
/**
* Checks if this PdfObject is of the type
* PdfName.
*
* @return true or false
*/
public boolean isName() {
return (type == NAME);
}
/**
* Checks if this PdfObject is of the type
* PdfArray.
*
* @return true or false
*/
public boolean isArray() {
return (type == ARRAY);
}
/**
* Checks if this PdfObject is of the type
* PdfDictionary.
*
* @return true or false
*/
public boolean isDictionary() {
return (type == DICTIONARY);
}
/**
* Checks if this PdfObject is of the type
* PdfStream.
*
* @return true or false
*/
public boolean isStream() {
return (type == STREAM);
}
/**
* Checks if this PdfObject is of the type
* PdfIndirectObject.
*
* @return true if this is an indirect object,
* otherwise false
*/
public boolean isIndirect() {
return (type == INDIRECT);
}
/**
* Get the indirect reference
*
* @return A PdfIndirectReference
*/
public PRIndirectReference getIndRef() {
return indRef;
}
/**
* Set the indirect reference
*
* @param indRef New value as a PdfIndirectReference
*/
public void setIndRef(PRIndirectReference indRef) {
this.indRef = indRef;
}
}