io.milton.common.FileDeletingInputStream 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.
*/
package io.milton.common;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.*;
/**
* An inputstream to read a file, and to delete the file when this stream is closed
*
* This is useful for situations where you are using a local file to buffer the contents
* of remote data, and want to ensure that the temporary local file is deleted when
* it is no longer being used
*
* @author brad
*/
public class FileDeletingInputStream extends InputStream {
private static final Logger log = LoggerFactory.getLogger(FileDeletingInputStream.class);
private File tempFile;
private final InputStream wrapped;
public FileDeletingInputStream(File tempFile) throws FileNotFoundException {
this.tempFile = tempFile;
wrapped = new FileInputStream(tempFile);
}
@Override
public int read() throws IOException {
return wrapped.read();
}
@Override
public int read(byte[] b) throws IOException {
return wrapped.read(b);
}
@Override
public int read(byte[] b, int off, int len) throws IOException {
return wrapped.read(b, off, len);
}
@Override
public synchronized void reset() throws IOException {
wrapped.reset();
}
@Override
public void close() throws IOException {
try {
wrapped.close();
} finally {
if (!tempFile.delete()) {
log.error("Failed to delete: {}", tempFile.getAbsolutePath());
} else {
tempFile = null;
}
}
}
@Override
protected void finalize() throws Throwable {
if( tempFile != null && tempFile.exists() ) {
log.error("temporary file was not deleted. Was close called on the inputstream? Will attempt to delete: {}", tempFile.getAbsolutePath());
if( !tempFile.delete()) {
log.error("Still couldnt delete temporary file: {}", tempFile.getAbsolutePath());
}
}
super.finalize();
}
}