Home » openjdk-7 » java » awt » image » [javadoc | source]

    1   /*
    2    * Copyright (c) 1997, 2008, Oracle and/or its affiliates. All rights reserved.
    3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
    4    *
    5    * This code is free software; you can redistribute it and/or modify it
    6    * under the terms of the GNU General Public License version 2 only, as
    7    * published by the Free Software Foundation.  Oracle designates this
    8    * particular file as subject to the "Classpath" exception as provided
    9    * by Oracle in the LICENSE file that accompanied this code.
   10    *
   11    * This code is distributed in the hope that it will be useful, but WITHOUT
   12    * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   13    * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   14    * version 2 for more details (a copy is included in the LICENSE file that
   15    * accompanied this code).
   16    *
   17    * You should have received a copy of the GNU General Public License version
   18    * 2 along with this work; if not, write to the Free Software Foundation,
   19    * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   20    *
   21    * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   22    * or visit www.oracle.com if you need additional information or have any
   23    * questions.
   24    */
   25   
   26   /* ****************************************************************
   27    ******************************************************************
   28    ******************************************************************
   29    *** COPYRIGHT (c) Eastman Kodak Company, 1997
   30    *** As  an unpublished  work pursuant to Title 17 of the United
   31    *** States Code.  All rights reserved.
   32    ******************************************************************
   33    ******************************************************************
   34    ******************************************************************/
   35   
   36   package java.awt.image;
   37   
   38   import static sun.java2d.StateTrackable.State.*;
   39   
   40   /**
   41    * This class extends <CODE>DataBuffer</CODE> and stores data internally as bytes.
   42    * Values stored in the byte array(s) of this <CODE>DataBuffer</CODE> are treated as
   43    * unsigned values.
   44    * <p>
   45    * <a name="optimizations">
   46    * Note that some implementations may function more efficiently
   47    * if they can maintain control over how the data for an image is
   48    * stored.
   49    * For example, optimizations such as caching an image in video
   50    * memory require that the implementation track all modifications
   51    * to that data.
   52    * Other implementations may operate better if they can store the
   53    * data in locations other than a Java array.
   54    * To maintain optimum compatibility with various optimizations
   55    * it is best to avoid constructors and methods which expose the
   56    * underlying storage as a Java array, as noted below in the
   57    * documentation for those methods.
   58    * </a>
   59    */
   60   public final class DataBufferByte extends DataBuffer
   61   {
   62       /** The default data bank. */
   63       byte data[];
   64   
   65       /** All data banks */
   66       byte bankdata[][];
   67   
   68       /**
   69        * Constructs a byte-based <CODE>DataBuffer</CODE> with a single bank and the
   70        * specified size.
   71        *
   72        * @param size The size of the <CODE>DataBuffer</CODE>.
   73        */
   74       public DataBufferByte(int size) {
   75         super(STABLE, TYPE_BYTE, size);
   76         data = new byte[size];
   77         bankdata = new byte[1][];
   78         bankdata[0] = data;
   79       }
   80   
   81       /**
   82        * Constructs a byte based <CODE>DataBuffer</CODE> with the specified number of
   83        * banks all of which are the specified size.
   84        *
   85        * @param size The size of the banks in the <CODE>DataBuffer</CODE>.
   86        * @param numBanks The number of banks in the a<CODE>DataBuffer</CODE>.
   87        */
   88       public DataBufferByte(int size, int numBanks) {
   89           super(STABLE, TYPE_BYTE, size, numBanks);
   90           bankdata = new byte[numBanks][];
   91           for (int i= 0; i < numBanks; i++) {
   92               bankdata[i] = new byte[size];
   93           }
   94           data = bankdata[0];
   95       }
   96   
   97       /**
   98        * Constructs a byte-based <CODE>DataBuffer</CODE> with a single bank using the
   99        * specified array.
  100        * Only the first <CODE>size</CODE> elements should be used by accessors of
  101        * this <CODE>DataBuffer</CODE>.  <CODE>dataArray</CODE> must be large enough to
  102        * hold <CODE>size</CODE> elements.
  103        * <p>
  104        * Note that {@code DataBuffer} objects created by this constructor
  105        * may be incompatible with <a href="#optimizations">performance
  106        * optimizations</a> used by some implementations (such as caching
  107        * an associated image in video memory).
  108        *
  109        * @param dataArray The byte array for the <CODE>DataBuffer</CODE>.
  110        * @param size The size of the <CODE>DataBuffer</CODE> bank.
  111        */
  112       public DataBufferByte(byte dataArray[], int size) {
  113           super(UNTRACKABLE, TYPE_BYTE, size);
  114           data = dataArray;
  115           bankdata = new byte[1][];
  116           bankdata[0] = data;
  117       }
  118   
  119       /**
  120        * Constructs a byte-based <CODE>DataBuffer</CODE> with a single bank using the
  121        * specified array, size, and offset.  <CODE>dataArray</CODE> must have at least
  122        * <CODE>offset</CODE> + <CODE>size</CODE> elements.  Only elements <CODE>offset</CODE>
  123        * through <CODE>offset</CODE> + <CODE>size</CODE> - 1
  124        * should be used by accessors of this <CODE>DataBuffer</CODE>.
  125        * <p>
  126        * Note that {@code DataBuffer} objects created by this constructor
  127        * may be incompatible with <a href="#optimizations">performance
  128        * optimizations</a> used by some implementations (such as caching
  129        * an associated image in video memory).
  130        *
  131        * @param dataArray The byte array for the <CODE>DataBuffer</CODE>.
  132        * @param size The size of the <CODE>DataBuffer</CODE> bank.
  133        * @param offset The offset into the <CODE>dataArray</CODE>. <CODE>dataArray</CODE>
  134        * must have at least <CODE>offset</CODE> + <CODE>size</CODE> elements.
  135        */
  136       public DataBufferByte(byte dataArray[], int size, int offset){
  137           super(UNTRACKABLE, TYPE_BYTE, size, 1, offset);
  138           data = dataArray;
  139           bankdata = new byte[1][];
  140           bankdata[0] = data;
  141       }
  142   
  143       /**
  144        * Constructs a byte-based <CODE>DataBuffer</CODE> with the specified arrays.
  145        * The number of banks is equal to <CODE>dataArray.length</CODE>.
  146        * Only the first <CODE>size</CODE> elements of each array should be used by
  147        * accessors of this <CODE>DataBuffer</CODE>.
  148        * <p>
  149        * Note that {@code DataBuffer} objects created by this constructor
  150        * may be incompatible with <a href="#optimizations">performance
  151        * optimizations</a> used by some implementations (such as caching
  152        * an associated image in video memory).
  153        *
  154        * @param dataArray The byte arrays for the <CODE>DataBuffer</CODE>.
  155        * @param size The size of the banks in the <CODE>DataBuffer</CODE>.
  156        */
  157       public DataBufferByte(byte dataArray[][], int size) {
  158           super(UNTRACKABLE, TYPE_BYTE, size, dataArray.length);
  159           bankdata = (byte[][]) dataArray.clone();
  160           data = bankdata[0];
  161       }
  162   
  163       /**
  164        * Constructs a byte-based <CODE>DataBuffer</CODE> with the specified arrays, size,
  165        * and offsets.
  166        * The number of banks is equal to <CODE>dataArray.length</CODE>.  Each array must
  167        * be at least as large as <CODE>size</CODE> + the corresponding <CODE>offset</CODE>.
  168        * There must be an entry in the <CODE>offset</CODE> array for each <CODE>dataArray</CODE>
  169        * entry.  For each bank, only elements <CODE>offset</CODE> through
  170        * <CODE>offset</CODE> + <CODE>size</CODE> - 1 should be used by accessors of this
  171        * <CODE>DataBuffer</CODE>.
  172        * <p>
  173        * Note that {@code DataBuffer} objects created by this constructor
  174        * may be incompatible with <a href="#optimizations">performance
  175        * optimizations</a> used by some implementations (such as caching
  176        * an associated image in video memory).
  177        *
  178        * @param dataArray The byte arrays for the <CODE>DataBuffer</CODE>.
  179        * @param size The size of the banks in the <CODE>DataBuffer</CODE>.
  180        * @param offsets The offsets into each array.
  181        */
  182       public DataBufferByte(byte dataArray[][], int size, int offsets[]) {
  183           super(UNTRACKABLE, TYPE_BYTE, size, dataArray.length, offsets);
  184           bankdata = (byte[][]) dataArray.clone();
  185           data = bankdata[0];
  186       }
  187   
  188       /**
  189        * Returns the default (first) byte data array.
  190        * <p>
  191        * Note that calling this method may cause this {@code DataBuffer}
  192        * object to be incompatible with <a href="#optimizations">performance
  193        * optimizations</a> used by some implementations (such as caching
  194        * an associated image in video memory).
  195        *
  196        * @return The first byte data array.
  197        */
  198       public byte[] getData() {
  199           theTrackable.setUntrackable();
  200           return data;
  201       }
  202   
  203       /**
  204        * Returns the data array for the specified bank.
  205        * <p>
  206        * Note that calling this method may cause this {@code DataBuffer}
  207        * object to be incompatible with <a href="#optimizations">performance
  208        * optimizations</a> used by some implementations (such as caching
  209        * an associated image in video memory).
  210        *
  211        * @param bank The bank whose data array you want to get.
  212        * @return The data array for the specified bank.
  213        */
  214       public byte[] getData(int bank) {
  215           theTrackable.setUntrackable();
  216           return bankdata[bank];
  217       }
  218   
  219       /**
  220        * Returns the data arrays for all banks.
  221        * <p>
  222        * Note that calling this method may cause this {@code DataBuffer}
  223        * object to be incompatible with <a href="#optimizations">performance
  224        * optimizations</a> used by some implementations (such as caching
  225        * an associated image in video memory).
  226        *
  227        * @return All of the data arrays.
  228        */
  229       public byte[][] getBankData() {
  230           theTrackable.setUntrackable();
  231           return (byte[][]) bankdata.clone();
  232       }
  233   
  234       /**
  235        * Returns the requested data array element from the first (default) bank.
  236        *
  237        * @param i The data array element you want to get.
  238        * @return The requested data array element as an integer.
  239        * @see #setElem(int, int)
  240        * @see #setElem(int, int, int)
  241        */
  242       public int getElem(int i) {
  243           return (int)(data[i+offset]) & 0xff;
  244       }
  245   
  246       /**
  247        * Returns the requested data array element from the specified bank.
  248        *
  249        * @param bank The bank from which you want to get a data array element.
  250        * @param i The data array element you want to get.
  251        * @return The requested data array element as an integer.
  252        * @see #setElem(int, int)
  253        * @see #setElem(int, int, int)
  254        */
  255       public int getElem(int bank, int i) {
  256           return (int)(bankdata[bank][i+offsets[bank]]) & 0xff;
  257       }
  258   
  259       /**
  260        * Sets the requested data array element in the first (default) bank
  261        * to the specified value.
  262        *
  263        * @param i The data array element you want to set.
  264        * @param val The integer value to which you want to set the data array element.
  265        * @see #getElem(int)
  266        * @see #getElem(int, int)
  267        */
  268       public void setElem(int i, int val) {
  269           data[i+offset] = (byte)val;
  270           theTrackable.markDirty();
  271       }
  272   
  273       /**
  274        * Sets the requested data array element in the specified bank
  275        * from the given integer.
  276        * @param bank The bank in which you want to set the data array element.
  277        * @param i The data array element you want to set.
  278        * @param val The integer value to which you want to set the specified data array element.
  279        * @see #getElem(int)
  280        * @see #getElem(int, int)
  281        */
  282       public void setElem(int bank, int i, int val) {
  283           bankdata[bank][i+offsets[bank]] = (byte)val;
  284           theTrackable.markDirty();
  285       }
  286   }

Home » openjdk-7 » java » awt » image » [javadoc | source]