Java tutorial
/* * Copyright (c) 2000, 2018, Oracle and/or its affiliates. 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. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.awt.image; import static sun.java2d.StateTrackable.State.*; /** * This class extends {@code DataBuffer} and stores data internally * in {@code double} form. * <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> * * @since 1.4 */ public final class DataBufferDouble extends DataBuffer { /** The array of data banks. */ double[][] bankdata; /** A reference to the default data bank. */ double[] data; /** * Constructs a {@code double}-based {@code DataBuffer} * with a specified size. * * @param size The number of elements in the {@code DataBuffer}. */ public DataBufferDouble(int size) { super(STABLE, TYPE_DOUBLE, size); data = new double[size]; bankdata = new double[1][]; bankdata[0] = data; } /** * Constructs a {@code double}-based {@code DataBuffer} * with a specified number of banks, all of which are of a * specified size. * * @param size The number of elements in each bank of the * {@code DataBuffer}. * @param numBanks The number of banks in the {@code DataBuffer}. */ public DataBufferDouble(int size, int numBanks) { super(STABLE, TYPE_DOUBLE, size, numBanks); bankdata = new double[numBanks][]; for (int i = 0; i < numBanks; i++) { bankdata[i] = new double[size]; } data = bankdata[0]; } /** * Constructs a {@code double}-based {@code DataBuffer} * with the specified data array. Only the first * {@code size} elements are available for use by this * {@code DataBuffer}. The array 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 An array of {@code double}s to be used as the * first and only bank of this {@code DataBuffer}. * @param size The number of elements of the array to be used. */ public DataBufferDouble(double[] dataArray, int size) { super(UNTRACKABLE, TYPE_DOUBLE, size); data = dataArray; bankdata = new double[1][]; bankdata[0] = data; } /** * Constructs a {@code double}-based {@code DataBuffer} * with the specified data array. Only the elements between * {@code offset} and {@code offset + size - 1} are * available for use by this {@code DataBuffer}. The array * must be large enough to hold {@code offset + 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 An array of {@code double}s to be used as the * first and only bank of this {@code DataBuffer}. * @param size The number of elements of the array to be used. * @param offset The offset of the first element of the array * that will be used. */ public DataBufferDouble(double[] dataArray, int size, int offset) { super(UNTRACKABLE, TYPE_DOUBLE, size, 1, offset); data = dataArray; bankdata = new double[1][]; bankdata[0] = data; } /** * Constructs a {@code double}-based {@code DataBuffer} * with the specified data arrays. Only the first * {@code size} elements of each array are available for use * by this {@code DataBuffer}. The number of banks will be * equal {@code to dataArray.length}. * <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 An array of arrays of {@code double}s to be * used as the banks of this {@code DataBuffer}. * @param size The number of elements of each array to be used. */ public DataBufferDouble(double[][] dataArray, int size) { super(UNTRACKABLE, TYPE_DOUBLE, size, dataArray.length); bankdata = dataArray.clone(); data = bankdata[0]; } /** * Constructs a {@code double}-based {@code DataBuffer} * with the specified data arrays, size, and per-bank offsets. * The number of banks is equal to dataArray.length. Each array * must be at least as large as {@code size} plus the * corresponding offset. There must be an entry in the * {@code offsets} array for each data array. * <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 An array of arrays of {@code double}s to be * used as the banks of this {@code DataBuffer}. * @param size The number of elements of each array to be used. * @param offsets An array of integer offsets, one for each bank. */ public DataBufferDouble(double[][] dataArray, int size, int[] offsets) { super(UNTRACKABLE, TYPE_DOUBLE, size, dataArray.length, offsets); bankdata = dataArray.clone(); data = bankdata[0]; } /** * Returns the default (first) {@code double} 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 double data array. */ public double[] 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 data array * @return the data array specified by {@code bank}. */ public double[] getData(int bank) { theTrackable.setUntrackable(); return bankdata[bank]; } /** * Returns the data array 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 data arrays from this data buffer. */ public double[][] getBankData() { theTrackable.setUntrackable(); return bankdata.clone(); } /** * Returns the requested data array element from the first * (default) bank as an {@code int}. * * @param i The desired data array element. * @return The data entry as an {@code int}. * @see #setElem(int, int) * @see #setElem(int, int, int) */ public int getElem(int i) { return (int) (data[i + offset]); } /** * Returns the requested data array element from the specified * bank as an {@code int}. * * @param bank The bank number. * @param i The desired data array element. * * @return The data entry as an {@code int}. * @see #setElem(int, int) * @see #setElem(int, int, int) */ public int getElem(int bank, int i) { return (int) (bankdata[bank][i + offsets[bank]]); } /** * Sets the requested data array element in the first (default) * bank to the given {@code int}. * * @param i The desired data array element. * @param val The value to be set. * @see #getElem(int) * @see #getElem(int, int) */ public void setElem(int i, int val) { data[i + offset] = (double) val; theTrackable.markDirty(); } /** * Sets the requested data array element in the specified bank * to the given {@code int}. * * @param bank The bank number. * @param i The desired data array element. * @param val The value to be set. * @see #getElem(int) * @see #getElem(int, int) */ public void setElem(int bank, int i, int val) { bankdata[bank][i + offsets[bank]] = (double) val; theTrackable.markDirty(); } /** * Returns the requested data array element from the first * (default) bank as a {@code float}. * * @param i The desired data array element. * * @return The data entry as a {@code float}. * @see #setElemFloat(int, float) * @see #setElemFloat(int, int, float) */ public float getElemFloat(int i) { return (float) data[i + offset]; } /** * Returns the requested data array element from the specified * bank as a {@code float}. * * @param bank The bank number. * @param i The desired data array element. * * @return The data entry as a {@code float}. * @see #setElemFloat(int, float) * @see #setElemFloat(int, int, float) */ public float getElemFloat(int bank, int i) { return (float) bankdata[bank][i + offsets[bank]]; } /** * Sets the requested data array element in the first (default) * bank to the given {@code float}. * * @param i The desired data array element. * @param val The value to be set. * @see #getElemFloat(int) * @see #getElemFloat(int, int) */ public void setElemFloat(int i, float val) { data[i + offset] = (double) val; theTrackable.markDirty(); } /** * Sets the requested data array element in the specified bank to * the given {@code float}. * * @param bank The bank number. * @param i The desired data array element. * @param val The value to be set. * @see #getElemFloat(int) * @see #getElemFloat(int, int) */ public void setElemFloat(int bank, int i, float val) { bankdata[bank][i + offsets[bank]] = (double) val; theTrackable.markDirty(); } /** * Returns the requested data array element from the first * (default) bank as a {@code double}. * * @param i The desired data array element. * * @return The data entry as a {@code double}. * @see #setElemDouble(int, double) * @see #setElemDouble(int, int, double) */ public double getElemDouble(int i) { return data[i + offset]; } /** * Returns the requested data array element from the specified * bank as a {@code double}. * * @param bank The bank number. * @param i The desired data array element. * * @return The data entry as a {@code double}. * @see #setElemDouble(int, double) * @see #setElemDouble(int, int, double) */ public double getElemDouble(int bank, int i) { return bankdata[bank][i + offsets[bank]]; } /** * Sets the requested data array element in the first (default) * bank to the given {@code double}. * * @param i The desired data array element. * @param val The value to be set. * @see #getElemDouble(int) * @see #getElemDouble(int, int) */ public void setElemDouble(int i, double val) { data[i + offset] = val; theTrackable.markDirty(); } /** * Sets the requested data array element in the specified bank to * the given {@code double}. * * @param bank The bank number. * @param i The desired data array element. * @param val The value to be set. * @see #getElemDouble(int) * @see #getElemDouble(int, int) */ public void setElemDouble(int bank, int i, double val) { bankdata[bank][i + offsets[bank]] = val; theTrackable.markDirty(); } }