/*
 * 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.ozone.client.io;

import java.io.FilterInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
import org.apache.hadoop.fs.ByteBufferReadable;

/**
 * An input stream with length.
 */
public class LengthInputStream extends FilterInputStream implements
    ByteBufferReadable {

  private final long length;

  /**
   * Create an stream.
   * @param in the underlying input stream.
   * @param length the length of the stream.
   */
  public LengthInputStream(InputStream in, long length) {
    super(in);
    this.length = length;
  }

  /** @return the length. */
  public long getLength() {
    return length;
  }

  public InputStream getWrappedStream() {
    return in;
  }

  @Override
  public int read(ByteBuffer byteBuffer) throws IOException {
    if (in instanceof ByteBufferReadable) {
      return ((ByteBufferReadable)in).read(byteBuffer);
    } else {
      throw new UnsupportedOperationException("Read with ByteBuffer is not " +
          " supported by " + in.getClass().getName());
    }
  }
}
