/*
* 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 org.apache.hadoop.io.compress;
import java.io.IOException;
import java.io.InputStream;
/**
* A compression input stream.
*
* <p>Implementations are assumed to be buffered. This permits clients to
* reposition the underlying input stream then call {@link #resetState()},
* without having to also synchronize client buffers.
*/
public abstract class CompressionInputStream extends InputStream {
/**
* The input stream to be compressed.
*/
protected final InputStream in;
/**
* Create a compression input stream that reads
* the decompressed bytes from the given stream.
*
* @param in The input stream to be compressed.
*/
protected CompressionInputStream(InputStream in) {
this.in = in;
}
public void close() throws IOException {
in.close();
}
/**
* Read bytes from the stream.
* Made abstract to prevent leakage to underlying stream.
*/
public abstract int read(byte[] b, int off, int len) throws IOException;
/**
* Reset the decompressor to its initial state and discard any buffered data,
* as the underlying stream may have been repositioned.
*/
public abstract void resetState() throws IOException;
}