/*
* Copyright 2013-2014 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file 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 com.amazonaws.internal;
import static com.amazonaws.util.SdkRuntime.shouldAbort;
import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;
import com.amazonaws.AbortedException;
import com.amazonaws.util.IOUtils;
/**
* Base class for AWS Java SDK specific {@link FilterInputStream}.
*/
public class SdkFilterInputStream extends FilterInputStream implements
MetricAware, Releasable {
protected SdkFilterInputStream(InputStream in) {
super(in);
}
@Override
public boolean isMetricActivated() {
if (in instanceof MetricAware) {
MetricAware metricAware = (MetricAware)in;
return metricAware.isMetricActivated();
}
return false;
}
/**
* Aborts with subclass specific abortion logic executed if needed.
* Note the interrupted status of the thread is cleared by this method.
* @throws AbortedException if found necessary.
*/
protected final void abortIfNeeded() {
if (shouldAbort()) {
abort(); // execute subclass specific abortion logic
throw new AbortedException();
}
}
/**
* Can be used to provide abortion logic prior to throwing the
* AbortedException. No-op by default.
*/
protected void abort() {
// no-op by default, but subclass such as S3ObjectInputStream may override
}
@Override
public int read() throws IOException {
abortIfNeeded();
return in.read();
}
@Override
public int read(byte b[], int off, int len) throws IOException {
abortIfNeeded();
return in.read(b, off, len);
}
@Override
public long skip(long n) throws IOException {
abortIfNeeded();
return in.skip(n);
}
@Override
public int available() throws IOException {
abortIfNeeded();
return in.available();
}
@Override
public void close() throws IOException {
in.close();
abortIfNeeded();
}
@Override
public synchronized void mark(int readlimit) {
abortIfNeeded();
in.mark(readlimit);
}
@Override
public synchronized void reset() throws IOException {
abortIfNeeded();
in.reset();
}
@Override
public boolean markSupported() {
abortIfNeeded();
return in.markSupported();
}
@Override
public void release() {
// Don't call IOUtils.release(in, null) or else could lead to infinite loop
IOUtils.closeQuietly(this, null);
if (in instanceof Releasable) {
// This allows any underlying stream that has the close operation
// disabled to be truly released
Releasable r = (Releasable)in;
r.release();
}
}
}