Java ByteBuffer to Stream toStream(ByteBuffer byteBuffer)

Description

Wraps a ByteBuffer in an InputStream.

License

Open Source License

Parameter

Parameter	Description
byteBuffer	The ByteBuffer to wrap.

Return

An InputStream wrapping the ByteBuffer content.

Declaration

public static ByteArrayInputStream toStream(ByteBuffer byteBuffer) 

Method Source Code

//package com.java2s;
/*/*from w  w w  .  java 2 s  .c o m*/
 * Copyright 2010-2016 ksyun.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Portions copyright 2006-2009 James Murty. Please see LICENSE.txt
 * for applicable license terms and NOTICE.txt for applicable notices.
 *
 * 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://ksyun.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.
 */

import java.io.ByteArrayInputStream;
import java.nio.ByteBuffer;
import java.util.Arrays;

public class Main {
    /**
     * Wraps a ByteBuffer in an InputStream. If the input {@code byteBuffer}
     * is null, returns an empty stream.
     *
     * @param byteBuffer The ByteBuffer to wrap.
     *
     * @return An InputStream wrapping the ByteBuffer content.
     */
    public static ByteArrayInputStream toStream(ByteBuffer byteBuffer) {
        if (byteBuffer == null) {
            return new ByteArrayInputStream(new byte[0]);
        }
        return new ByteArrayInputStream(copyBytesFrom(byteBuffer));
    }

    /**
     * Returns a copy of the bytes from the given <code>ByteBuffer</code>,
     * ranging from the the buffer's current position to the buffer's limit; or
     * null if the input is null.
     * <p>
     * The internal states of the given byte buffer will be restored when this
     * method completes execution.
     * <p>
     * When handling <code>ByteBuffer</code> from user's input, it's typical to
     * call the {@link #copyBytesFrom(ByteBuffer)} instead of
     * {@link #copyAllBytesFrom(ByteBuffer)} so as to account for the position
     * of the input <code>ByteBuffer</code>. The opposite is typically true,
     * however, when handling <code>ByteBuffer</code> from withint the
     * unmarshallers of the low-level clients.
     */
    public static byte[] copyBytesFrom(ByteBuffer bb) {
        if (bb == null) {
            return null;
        }

        if (bb.hasArray()) {
            return Arrays.copyOfRange(bb.array(), bb.arrayOffset() + bb.position(), bb.arrayOffset() + bb.limit());
        }

        byte[] dst = new byte[bb.remaining()];
        bb.asReadOnlyBuffer().get(dst);
        return dst;
    }
}

Related

1. toStream(ByteBuffer byteBuffer)