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 *
 * 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
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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 *** As  an unpublished  work pursuant to Title 17 of the United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} and stores data internally as bytes.
 * Values stored in the byte array(s) of this {@code DataBuffer} are treated as
 * unsigned values.
 * <p>
 * <a id="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. 
/** The default data bank. */
    byte data[];

    
All data banks 
/** All data banks */
    byte bankdata[][];

    
Constructs a byte-based DataBuffer with a single bank and the specified size. 
Params:
  • size – The size of the DataBuffer.
/**
     * Constructs a byte-based {@code DataBuffer} with a single bank and the
     * specified size.
     *
     * @param size The size of the {@code DataBuffer}.
     */
    public DataBufferByte(int size) {
      super(STABLE, TYPE_BYTE, size);
      data = new byte[size];
      bankdata = new byte[1][];
      bankdata[0] = data;
    }

    
Constructs a byte based DataBuffer with the specified number of banks all of which are the specified size. 
Params:
  • size – The size of the banks in the DataBuffer.
  • numBanks – The number of banks in the a DataBuffer.
/**
     * Constructs a byte based {@code DataBuffer} with the specified number of
     * banks all of which are the specified size.
     *
     * @param size The size of the banks in the {@code DataBuffer}.
     * @param numBanks The number of banks in the a {@code DataBuffer}.
     */
    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 DataBuffer with a single bank using the specified array. Only the first size elements should be used by accessors of this DataBuffer. dataArray must be large enough to hold size elements. 
 Note that DataBuffer objects created by this constructor may be incompatible with performance
optimizations used by some implementations (such as caching
an associated image in video memory).

Params:
  • dataArray – The byte array for the DataBuffer.
  • size – The size of the DataBuffer bank.
/**
     * Constructs a byte-based {@code DataBuffer} with a single bank using the
     * specified array.
     * Only the first {@code size} elements should be used by accessors of
     * this {@code DataBuffer}.  {@code dataArray} must be large enough to
     * hold {@code size} 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}.
     * @param size The size of the {@code DataBuffer} 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 DataBuffer with a single bank using the specified array, size, and offset. dataArray must have at least offset + size elements. Only elements offset through offset + size - 1 should be used by accessors of this DataBuffer. 
 Note that DataBuffer objects created by this constructor may be incompatible with performance
optimizations used by some implementations (such as caching
an associated image in video memory).

Params:
  • dataArray – The byte array for the DataBuffer.
  • size – The size of the DataBuffer bank.
  • offset – The offset into the dataArray. dataArray must have at least offset + size elements.
/**
     * Constructs a byte-based {@code DataBuffer} with a single bank using the
     * specified array, size, and offset.  {@code dataArray} must have at least
     * {@code offset} + {@code size} elements.  Only elements {@code offset}
     * through {@code offset} + {@code size} - 1
     * should be used by accessors of this {@code DataBuffer}.
     * <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}.
     * @param size The size of the {@code DataBuffer} bank.
     * @param offset The offset into the {@code dataArray}. {@code dataArray}
     * must have at least {@code offset} + {@code size} 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 DataBuffer with the specified arrays. The number of banks is equal to dataArray.length. Only the first size elements of each array should be used by accessors of this DataBuffer. 
 Note that DataBuffer objects created by this constructor may be incompatible with performance
optimizations used by some implementations (such as caching
an associated image in video memory).

Params:
  • dataArray – The byte arrays for the DataBuffer.
  • size – The size of the banks in the DataBuffer.
/**
     * Constructs a byte-based {@code DataBuffer} with the specified arrays.
     * The number of banks is equal to {@code dataArray.length}.
     * Only the first {@code size} elements of each array should be used by
     * accessors of this {@code DataBuffer}.
     * <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}.
     * @param size The size of the banks in the {@code DataBuffer}.
     */
    public DataBufferByte(byte dataArray[][], int size) {
        super(UNTRACKABLE, TYPE_BYTE, size, dataArray.length);
        bankdata = dataArray.clone();
        data = bankdata[0];
    }

    
Constructs a byte-based DataBuffer with the specified arrays, size, and offsets. The number of banks is equal to dataArray.length. Each array must be at least as large as size + the corresponding offset. There must be an entry in the offset array for each dataArray entry. For each bank, only elements offset through offset + size - 1 should be used by accessors of this DataBuffer. 
 Note that DataBuffer objects created by this constructor may be incompatible with performance
optimizations used by some implementations (such as caching
an associated image in video memory).

Params:
  • dataArray – The byte arrays for the DataBuffer.
  • size – The size of the banks in the DataBuffer.
  • offsets – The offsets into each array.
/**
     * Constructs a byte-based {@code DataBuffer} with the specified arrays, size,
     * and offsets.
     * The number of banks is equal to {@code dataArray.length}.  Each array must
     * be at least as large as {@code size} + the corresponding {@code offset}.
     * There must be an entry in the {@code offset} array for each {@code dataArray}
     * entry.  For each bank, only elements {@code offset} through
     * {@code offset} + {@code size} - 1 should be used by accessors of this
     * {@code DataBuffer}.
     * <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}.
     * @param size The size of the banks in the {@code DataBuffer}.
     * @param offsets The offsets into each array.
     */
    public DataBufferByte(byte dataArray[][], int size, int offsets[]) {
        super(UNTRACKABLE, TYPE_BYTE, size, dataArray.length, offsets);
        bankdata = dataArray.clone();
        data = bankdata[0];
    }

    
Returns the default (first) byte data array.

 Note that calling this method may cause this DataBuffer object to be incompatible with performance
optimizations used by some implementations (such as caching
an associated image in video memory).

Returns:The first byte data array.
/**
     * 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.

 Note that calling this method may cause this DataBuffer object to be incompatible with performance
optimizations used by some implementations (such as caching
an associated image in video memory).

Params:
  • bank – The bank whose data array you want to get.
Returns:The data array for the specified bank.
/**
     * 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.

 Note that calling this method may cause this DataBuffer object to be incompatible with performance
optimizations used by some implementations (such as caching
an associated image in video memory).

Returns:All of the data arrays.
/**
     * 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 bankdata.clone();
    }

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

Params:
  • i – The data array element you want to get.
See Also:
Returns:The requested data array element as an integer.
/**
     * 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.

Params:
  • bank – The bank from which you want to get a data array element.
  • i – The data array element you want to get.
See Also:
Returns:The requested data array element as an integer.
/**
     * 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.

Params:
  • i – The data array element you want to set.
  • val – The integer value to which you want to set the data array element.
See Also:
/**
     * 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.

Params:
  • bank – The bank in which you want to set the data array element.
  • i – The data array element you want to set.
  • val – The integer value to which you want to set the specified data array element.
See Also:
/**
     * 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();
    }
}