Java tutorial
/* * Copyright 2014-2016 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 core.com.qiniu.internal; import org.apache.commons.logging.LogFactory; import java.io.IOException; import java.io.InputStream; import core.com.qiniu.AbortedException; /** * Base class for AWS Java SDK specific {@link InputStream}. */ public abstract class SdkInputStream extends InputStream implements MetricAware { /** * Returns the underlying input stream, if any, from the subclass; or null * if there is no underlying input stream. */ abstract protected InputStream getWrappedInputStream(); @Override @Deprecated public final boolean isMetricActivated() { InputStream in = getWrappedInputStream(); 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 (Thread.interrupted()) { try { abort(); // execute subclass specific abortion logic } catch (IOException e) { LogFactory.getLog(getClass()).debug("FYI", e); } throw new AbortedException(); } } /** * Can be used to provide abortion logic prior to throwing the * AbortedException. No-op by default. */ protected void abort() throws IOException { // no-op by default, but subclass such as S3ObjectInputStream may // override } }