/*

 * 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

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 */

/* ****************************************************************

 ******************************************************************

 ******************************************************************

 *** COPYRIGHT (c) Eastman Kodak Company, 1997

 *** As  an unpublished  work pursuant to Title 17 of the United

 *** States Code.  All rights reserved.

 ******************************************************************

 ******************************************************************

 ******************************************************************/

package java.awt.image;

import static sun.java2d.StateTrackable.State.*;

/**

 * This class extends <CODE>DataBuffer</CODE> and stores data internally as bytes.

 * Values stored in the byte array(s) of this <CODE>DataBuffer</CODE> are treated as

 * unsigned values.

 * <p>

 * <a name="optimizations">

 * Note that some implementations may function more efficiently

 * if they can maintain control over how the data for an image is

 * stored.

 * For example, optimizations such as caching an image in video

 * memory require that the implementation track all modifications

 * to that data.

 * Other implementations may operate better if they can store the

 * data in locations other than a Java array.

 * To maintain optimum compatibility with various optimizations

 * it is best to avoid constructors and methods which expose the

 * underlying storage as a Java array, as noted below in the

 * documentation for those methods.

 * </a>

 */

public final class DataBufferByte extends DataBuffer

{

    /** The default data bank. */

    byte data[];

    /** All data banks */

    byte bankdata[][];

    /**

     * Constructs a byte-based <CODE>DataBuffer</CODE> with a single bank and the

     * specified size.

     *

     * @param size The size of the <CODE>DataBuffer</CODE>.

     */

    public DataBufferByte(int size) {

      super(STABLE, TYPE_BYTE, size);

      data = new byte[size];

      bankdata = new byte[1][];

      bankdata[0] = data;

    }

    /**

     * Constructs a byte based <CODE>DataBuffer</CODE> with the specified number of

     * banks all of which are the specified size.

     *

     * @param size The size of the banks in the <CODE>DataBuffer</CODE>.

     * @param numBanks The number of banks in the a<CODE>DataBuffer</CODE>.

     */

    public DataBufferByte(int size, int numBanks) {

        super(STABLE, TYPE_BYTE, size, numBanks);

        bankdata = new byte[numBanks][];

        for (int i= 0; i < numBanks; i++) {

            bankdata[i] = new byte[size];

        }

        data = bankdata[0];

    }

    /**

     * Constructs a byte-based <CODE>DataBuffer</CODE> with a single bank using the

     * specified array.

     * Only the first <CODE>size</CODE> elements should be used by accessors of

     * this <CODE>DataBuffer</CODE>.  <CODE>dataArray</CODE> must be large enough to

     * hold <CODE>size</CODE> elements.

     * <p>

     * Note that {@code DataBuffer} objects created by this constructor

     * may be incompatible with <a href="#optimizations">performance

     * optimizations</a> used by some implementations (such as caching

     * an associated image in video memory).

     *

     * @param dataArray The byte array for the <CODE>DataBuffer</CODE>.

     * @param size The size of the <CODE>DataBuffer</CODE> bank.

     */

    public DataBufferByte(byte dataArray[], int size) {

        super(UNTRACKABLE, TYPE_BYTE, size);

        data = dataArray;

        bankdata = new byte[1][];

        bankdata[0] = data;

    }

    /**

     * Constructs a byte-based <CODE>DataBuffer</CODE> with a single bank using the

     * specified array, size, and offset.  <CODE>dataArray</CODE> must have at least

     * <CODE>offset</CODE> + <CODE>size</CODE> elements.  Only elements <CODE>offset</CODE>

     * through <CODE>offset</CODE> + <CODE>size</CODE> - 1

     * should be used by accessors of this <CODE>DataBuffer</CODE>.

     * <p>

     * Note that {@code DataBuffer} objects created by this constructor

     * may be incompatible with <a href="#optimizations">performance

     * optimizations</a> used by some implementations (such as caching

     * an associated image in video memory).

     *

     * @param dataArray The byte array for the <CODE>DataBuffer</CODE>.

     * @param size The size of the <CODE>DataBuffer</CODE> bank.

     * @param offset The offset into the <CODE>dataArray</CODE>. <CODE>dataArray</CODE>

     * must have at least <CODE>offset</CODE> + <CODE>size</CODE> elements.

     */

    public DataBufferByte(byte dataArray[], int size, int offset){

        super(UNTRACKABLE, TYPE_BYTE, size, 1, offset);

        data = dataArray;

        bankdata = new byte[1][];

        bankdata[0] = data;

    }

    /**

     * Constructs a byte-based <CODE>DataBuffer</CODE> with the specified arrays.

     * The number of banks is equal to <CODE>dataArray.length</CODE>.

     * Only the first <CODE>size</CODE> elements of each array should be used by

     * accessors of this <CODE>DataBuffer</CODE>.

     * <p>

     * Note that {@code DataBuffer} objects created by this constructor

     * may be incompatible with <a href="#optimizations">performance

     * optimizations</a> used by some implementations (such as caching

     * an associated image in video memory).

     *

     * @param dataArray The byte arrays for the <CODE>DataBuffer</CODE>.

     * @param size The size of the banks in the <CODE>DataBuffer</CODE>.

     */

    public DataBufferByte(byte dataArray[][], int size) {

        super(UNTRACKABLE, TYPE_BYTE, size, dataArray.length);

        bankdata = (byte[][]) dataArray.clone();

        data = bankdata[0];

    }

    /**

     * Constructs a byte-based <CODE>DataBuffer</CODE> with the specified arrays, size,

     * and offsets.

     * The number of banks is equal to <CODE>dataArray.length</CODE>.  Each array must

     * be at least as large as <CODE>size</CODE> + the corresponding <CODE>offset</CODE>.

     * There must be an entry in the <CODE>offset</CODE> array for each <CODE>dataArray</CODE>

     * entry.  For each bank, only elements <CODE>offset</CODE> through

     * <CODE>offset</CODE> + <CODE>size</CODE> - 1 should be used by accessors of this

     * <CODE>DataBuffer</CODE>.

     * <p>

     * Note that {@code DataBuffer} objects created by this constructor

     * may be incompatible with <a href="#optimizations">performance

     * optimizations</a> used by some implementations (such as caching

     * an associated image in video memory).

     *

     * @param dataArray The byte arrays for the <CODE>DataBuffer</CODE>.

     * @param size The size of the banks in the <CODE>DataBuffer</CODE>.

     * @param offsets The offsets into each array.

     */

    public DataBufferByte(byte dataArray[][], int size, int offsets[]) {

        super(UNTRACKABLE, TYPE_BYTE, size, dataArray.length, offsets);

        bankdata = (byte[][]) dataArray.clone();

        data = bankdata[0];

    }

    /**

     * Returns the default (first) byte data array.

     * <p>

     * Note that calling this method may cause this {@code DataBuffer}

     * object to be incompatible with <a href="#optimizations">performance

     * optimizations</a> used by some implementations (such as caching

     * an associated image in video memory).

     *

     * @return The first byte data array.

     */

    public byte[] getData() {

        theTrackable.setUntrackable();

        return data;

    }

    /**

     * Returns the data array for the specified bank.

     * <p>

     * Note that calling this method may cause this {@code DataBuffer}

     * object to be incompatible with <a href="#optimizations">performance

     * optimizations</a> used by some implementations (such as caching

     * an associated image in video memory).

     *

     * @param bank The bank whose data array you want to get.

     * @return The data array for the specified bank.

     */

    public byte[] getData(int bank) {

        theTrackable.setUntrackable();

        return bankdata[bank];

    }

    /**

     * Returns the data arrays for all banks.

     * <p>

     * Note that calling this method may cause this {@code DataBuffer}

     * object to be incompatible with <a href="#optimizations">performance

     * optimizations</a> used by some implementations (such as caching

     * an associated image in video memory).

     *

     * @return All of the data arrays.

     */

    public byte[][] getBankData() {

        theTrackable.setUntrackable();

        return (byte[][]) bankdata.clone();

    }

    /**

     * Returns the requested data array element from the first (default) bank.

     *

     * @param i The data array element you want to get.

     * @return The requested data array element as an integer.

     * @see #setElem(int, int)

     * @see #setElem(int, int, int)

     */

    public int getElem(int i) {

        return (int)(data[i+offset]) & 0xff;

    }

    /**

     * Returns the requested data array element from the specified bank.

     *

     * @param bank The bank from which you want to get a data array element.

     * @param i The data array element you want to get.

     * @return The requested data array element as an integer.

     * @see #setElem(int, int)

     * @see #setElem(int, int, int)

     */

    public int getElem(int bank, int i) {

        return (int)(bankdata[bank][i+offsets[bank]]) & 0xff;

    }

    /**

     * Sets the requested data array element in the first (default) bank

     * to the specified value.

     *

     * @param i The data array element you want to set.

     * @param val The integer value to which you want to set the data array element.

     * @see #getElem(int)

     * @see #getElem(int, int)

     */

    public void setElem(int i, int val) {

        data[i+offset] = (byte)val;

        theTrackable.markDirty();

    }

    /**

     * Sets the requested data array element in the specified bank

     * from the given integer.

     * @param bank The bank in which you want to set the data array element.

     * @param i The data array element you want to set.

     * @param val The integer value to which you want to set the specified data array element.

     * @see #getElem(int)

     * @see #getElem(int, int)

     */

    public void setElem(int bank, int i, int val) {

        bankdata[bank][i+offsets[bank]] = (byte)val;

        theTrackable.markDirty();

    }

}