org.apache.fop.pdf.TempFileStreamCache Maven / Gradle / Ivy
/*
* 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: TempFileStreamCache.java 1296526 2012-03-03 00:18:45Z gadams $ */
package org.apache.fop.pdf;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import org.apache.commons.io.IOUtils;
/**
* StreamCache implementation that uses temporary files rather than heap.
*/
public class TempFileStreamCache implements StreamCache {
/**
* The current output stream.
*/
private OutputStream output;
/**
* The temp file.
*/
private File tempFile;
/**
* Creates a new TempFileStreamCache.
*
* @throws IOException if there is an IO error
*/
public TempFileStreamCache() throws IOException {
tempFile = File.createTempFile("org.apache.fop.pdf.StreamCache-",
".temp");
tempFile.deleteOnExit();
}
/**
* Get the current OutputStream. Do not store it - it may change
* from call to call.
*
* @throws IOException if there is an IO error
* @return the output stream for this cache
*/
public OutputStream getOutputStream() throws IOException {
if (output == null) {
output = new java.io.BufferedOutputStream(
new java.io.FileOutputStream(tempFile));
}
return output;
}
/**
* {@inheritDoc}
*/
public void write(byte[] data) throws IOException {
getOutputStream().write(data);
}
/**
* Outputs the cached bytes to the given stream.
*
* @param out the output stream to write to
* @return the number of bytes written
* @throws IOException if there is an IO error
*/
public int outputContents(OutputStream out) throws IOException {
if (output == null) {
return 0;
}
output.close();
output = null;
// don't need a buffer because copy() is buffered
InputStream input = new java.io.FileInputStream(tempFile);
try {
return IOUtils.copy(input, out);
} finally {
IOUtils.closeQuietly(input);
}
}
/**
* Returns the current size of the stream.
*
* @throws IOException if there is an IO error
* @return the size of the cache
*/
public int getSize() throws IOException {
if (output != null) {
output.flush();
}
return (int) tempFile.length();
}
/**
* Clears and resets the cache.
*
* @throws IOException if there is an IO error
*/
public void clear() throws IOException {
if (output != null) {
output.close();
output = null;
}
if (tempFile.exists()) {
tempFile.delete();
}
}
}