http://xmlgraphics.apache.org/fop/: Apache FOP (Formatting Objects Processor) is the world's first print formatter driven by XSL formatting objects (XSL-FO) and the world's first output independent formatter. It is a Java application that reads a formatting object (FO) tree and renders the resulting pages to a specified output. Output formats currently supported include PDF, PCL, PS, AFP, TIFF, PNG, SVG, XML (area tree representation), Print, AWT and TXT. The primary output target is PDF. (Apache Software Foundation) 
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (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.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/* $Id: PDFEncryption.java 1484190 2013-05-18 22:25:52Z lbernardo $ */

package org.apache.fop.pdf;


This interface defines the contract for classes implementing PDF encryption.

/**
 * This interface defines the contract for classes implementing PDF encryption.
 */
public interface PDFEncryption {

    
Adds a PDFFilter to the PDFStream object

Params:
  • stream – the stream to add an encryption filter to
/**
     * Adds a PDFFilter to the PDFStream object
     * @param stream the stream to add an encryption filter to
     */
    void applyFilter(AbstractPDFStream stream);

    
Encrypt an array of bytes using a reference PDFObject for calculating
the encryption key.

Params:
  • data – data to encrypt
  • refObj – reference PDFObject
Returns:byte[] the encrypted data
/**
     * Encrypt an array of bytes using a reference PDFObject for calculating
     * the encryption key.
     * @param data data to encrypt
     * @param refObj reference PDFObject
     * @return byte[] the encrypted data
     */
    byte[] encrypt(byte[] data, PDFObject refObj);

    
Returns the /Encrypt entry in the file trailer dictionary.

Returns:the string "/Encrypt n g R\n" where n and g are the number and generation
of the document's encryption dictionary
/**
     * Returns the /Encrypt entry in the file trailer dictionary.
     *
     * @return the string "/Encrypt n g R\n" where n and g are the number and generation
     * of the document's encryption dictionary
     */
    String getTrailerEntry();

    
Returns the PDF version required by the current encryption algorithm.

Returns:the PDF Version
/**
     * Returns the PDF version required by the current encryption algorithm.
     * @return the PDF Version
     */
    Version getPDFVersion();
}