/*
* Copyright (c) 2010-2012 Eike Stepper (Berlin, Germany) and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Eike Stepper - initial API and implementation
*/
package org.eclipse.net4j.util.io;
import org.eclipse.net4j.util.WrappedException;
import org.eclipse.net4j.util.concurrent.TimeoutRuntimeException;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
/**
* @author Eike Stepper
* @since 3.1
*/
public class ExpectedFileInputStream extends FileInputStream
{
private long timeout = IOUtil.DEFAULT_TIMEOUT;
private File file;
private long expectedSize;
private long pos;
public ExpectedFileInputStream(File file, long expectedSize) throws FileNotFoundException
{
super(file);
this.file = file;
this.expectedSize = expectedSize;
}
public long getTimeout()
{
return timeout;
}
public void setTimeout(long timeout)
{
this.timeout = timeout;
}
@Override
public long skip(long n) throws IOException
{
waitForInput(n);
return super.skip(n);
}
@Override
public int read() throws IOException
{
waitForInput(1L);
return super.read();
}
@Override
public int read(byte[] b, int off, int len) throws IOException
{
waitForInput(len);
return super.read(b, off, len);
}
@Override
public int read(byte[] b) throws IOException
{
return read(b, 0, b.length);
}
private void waitForInput(long n) throws IOException
{
synchronized (this)
{
n = Math.min(n, expectedSize - pos);
long restSize = file.length() - pos;
long endTime = 0;
while (restSize < n)
{
long restTime;
if (endTime == 0)
{
endTime = System.currentTimeMillis() + timeout;
restTime = timeout;
}
else
{
restTime = endTime - System.currentTimeMillis();
}
if (restTime <= 0)
{
throw new TimeoutRuntimeException("Timeout while reading from " + file.getAbsolutePath());
}
try
{
wait(Math.min(100L, restTime));
}
catch (InterruptedException ex)
{
throw WrappedException.wrap(ex);
}
restSize = file.length() - pos;
}
pos += n;
}
}
}