/*

 * Copyright 1999-2001 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package javax.imageio.stream;

/**

 * A class representing a mutable reference to an array of bytes and

 * an offset and length within that array.  <code>IIOByteBuffer</code>

 * is used by <code>ImageInputStream</code> to supply a sequence of bytes

 * to the caller, possibly with fewer copies than using the conventional

 * <code>read</code> methods that take a user-supplied byte array.

 *

 * <p> The byte array referenced by an <code>IIOByteBuffer</code> will

 * generally be part of an internal data structure belonging to an

 * <code>ImageReader</code> implementation; its contents should be

 * considered read-only and must not be modified.

 *

 */

public class IIOByteBuffer {

    private byte[] data;

    private int offset;

    private int length;

    /**

     * Constructs an <code>IIOByteBuffer</code> that references a

     * given byte array, offset, and length.

     *

     * @param data a byte array.

     * @param offset an int offset within the array.

     * @param length an int specifying the length of the data of

     * interest within byte array, in bytes.

     */

    public IIOByteBuffer(byte[] data, int offset, int length) {

        this.data = data;

        this.offset = offset;

        this.length = length;

    }

    /**

     * Returns a reference to the byte array.  The returned value should

     * be treated as read-only, and only the portion specified by the

     * values of <code>getOffset</code> and <code>getLength</code> should

     * be used.

     *

     * @return a byte array reference.

     *

     * @see #getOffset

     * @see #getLength

     * @see #setData

     */

    public byte[] getData() {

        return data;

    }

    /**

     * Updates the array reference that will be returned by subsequent calls

     * to the <code>getData</code> method.

     *

     * @param data a byte array reference containing the new data value.

     *

     * @see #getData

     */

    public void setData(byte[] data) {

        this.data = data;

    }

    /**

     * Returns the offset within the byte array returned by

     * <code>getData</code> at which the data of interest start.

     *

     * @return an int offset.

     *

     * @see #getData

     * @see #getLength

     * @see #setOffset

     */

    public int getOffset() {

        return offset;

    }

    /**

     * Updates the value that will be returned by subsequent calls

     * to the <code>getOffset</code> method.

     *

     * @param offset an int containing the new offset value.

     *

     * @see #getOffset

     */

    public void setOffset(int offset) {

        this.offset = offset;

    }

    /**

     * Returns the length of the data of interest within the byte

     * array returned by <code>getData</code>.

     *

     * @return an int length.

     *

     * @see #getData

     * @see #getOffset

     * @see #setLength

     */

    public int getLength() {

        return length;

    }

    /**

     * Updates the value that will be returned by subsequent calls

     * to the <code>getLength</code> method.

     *

     * @param length an int containing the new length value.

     *

     * @see #getLength

     */

    public void setLength(int length) {

        this.length = length;

    }

}