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: StreamCache.java 1296526 2012-03-03 00:18:45Z gadams $ */

package org.apache.fop.pdf;

import java.io.IOException;
import java.io.OutputStream;


Interface used to store the bytes for a PDFStream. It's actually a generic
cached byte array. There's a factory that returns either an
in-memory or tempfile based implementation based on a
cacheToFile setting.

/**
 * Interface used to store the bytes for a PDFStream. It's actually a generic
 * cached byte array. There's a factory that returns either an
 * in-memory or tempfile based implementation based on a
 * cacheToFile setting.
 */
public interface StreamCache {

    
Get the current OutputStream. Do not store it - it may change
from call to call.

Throws:
Returns:an output stream for this cache
/**
     * Get the current OutputStream. Do not store it - it may change
     * from call to call.
     *
     * @return an output stream for this cache
     * @throws IOException if there is an IO error
     */
    OutputStream getOutputStream() throws IOException;

    
Convenience method for writing data to the stream cache.

Params:
  • data – byte array to write
Throws:
/**
     * Convenience method for writing data to the stream cache.
     * @param data byte array to write
     * @throws IOException if there is an IO error
     */
    void write(byte[] data) throws IOException;

    
Outputs the cached bytes to the given stream.

Params:
  • out – the stream to write to
Throws:
Returns:the number of bytes written
/**
     * Outputs the cached bytes to the given stream.
     *
     * @param out the stream to write to
     * @return the number of bytes written
     * @throws IOException if there is an IO error
     */
    int outputContents(OutputStream out) throws IOException;

    
Returns the current size of the stream.

Throws:
Returns:the size of the cache
/**
     * Returns the current size of the stream.
     *
     * @return the size of the cache
     * @throws IOException if there is an IO error
     */
    int getSize() throws IOException;

    
Clears and resets the cache.

Throws:
  • IOException – if there is an IO error
/**
     * Clears and resets the cache.
     *
     * @throws IOException if there is an IO error
     */
    void clear() throws IOException;
}