path: root/src/java/com/jogamp/common/nio/StructAccessor.java

/*
 * Copyright (c) 2003 Sun Microsystems, Inc. All Rights Reserved.
 * Copyright (c) 2010 JogAmp Community. All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 * 
 * - Redistribution of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * 
 * - Redistribution in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * 
 * Neither the name of Sun Microsystems, Inc. or the names of
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 * 
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
 * INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
 * PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN
 * MICROSYSTEMS, INC. ("SUN") AND ITS LICENSORS SHALL NOT BE LIABLE FOR
 * ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING, MODIFYING OR
 * DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL SUN OR
 * ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR FOR
 * DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE
 * DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY,
 * ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE, EVEN IF
 * SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 * 
 * You acknowledge that this software is not designed or intended for use
 * in the design, construction, operation or maintenance of any nuclear
 * facility.
 * 
 * Sun gratefully acknowledges that this software was originally authored
 * and developed by Kenneth Bradley Russell and Christopher John Kline.
 */
package com.jogamp.common.nio;

import java.nio.*;

/**
 * @author Kenneth Russel
 * @author Michael Bien
 */
public class StructAccessor {

    private ByteBuffer bb;
    private FloatBuffer fb;
    private IntBuffer ib;
    private ShortBuffer sb;
    private CharBuffer cb;
    private DoubleBuffer db;
    private LongBuffer lb;

    public StructAccessor(ByteBuffer bb) {
        // Setting of byte order is concession to native code which needs
        // to instantiate these
        this.bb = bb.order(ByteOrder.nativeOrder());
    }

    public ByteBuffer getBuffer() {
        return bb;
    }

    /** 
     * Returns a slice of the current ByteBuffer starting at the
     * specified byte offset and extending the specified number of
     * bytes. Note that this method is not thread-safe with respect to
     * the other methods in this class.
     */
    public ByteBuffer slice(int byteOffset, int byteLength) {
        bb.position(byteOffset);
        bb.limit(byteOffset + byteLength);
        ByteBuffer newBuf = bb.slice();
        bb.position(0);
        bb.limit(bb.capacity());
        return newBuf;
    }

    /** Retrieves the byte at the specified slot (byte offset). */
    public byte getByteAt(int slot) {
        return bb.get(slot);
    }

    /** Puts a byte at the specified slot (byte offset). */
    public void setByteAt(int slot, byte v) {
        bb.put(slot, v);
    }

    /** Retrieves the char at the specified slot (2-byte offset). */
    public char getCharAt(int slot) {
        return charBuffer().get(slot);
    }

    /** Puts a char at the specified slot (2-byte offset). */
    public void setCharAt(int slot, char v) {
        charBuffer().put(slot, v);
    }

    /** Retrieves the double at the specified slot (8-byte offset). */
    public double getDoubleAt(int slot) {
        return doubleBuffer().get(slot);
    }

    /** Puts a double at the specified slot (8-byte offset). */
    public void setDoubleAt(int slot, double v) {
        doubleBuffer().put(slot, v);
    }

    /** Retrieves the float at the specified slot (4-byte offset). */
    public float getFloatAt(int slot) {
        return floatBuffer().get(slot);
    }

    /** Puts a float at the specified slot (4-byte offset). */
    public void setFloatAt(int slot, float v) {
        floatBuffer().put(slot, v);
    }

    /** Retrieves the int at the specified slot (4-byte offset). */
    public int getIntAt(int slot) {
        return intBuffer().get(slot);
    }

    /** Puts a int at the specified slot (4-byte offset). */
    public void setIntAt(int slot, int v) {
        intBuffer().put(slot, v);
    }

    /** Retrieves the short at the specified slot (2-byte offset). */
    public short getShortAt(int slot) {
        return shortBuffer().get(slot);
    }

    /** Puts a short at the specified slot (2-byte offset). */
    public void setShortAt(int slot, short v) {
        shortBuffer().put(slot, v);
    }

    public void setBytesAt(int slot, byte[] v) {
        for (int i = 0; i < v.length; i++) {
            bb.put(slot++, v[i]);
        }
    }

    public byte[] getBytesAt(int slot, byte[] v) {
        for (int i = 0; i < v.length; i++) {
            v[i] = bb.get(slot++);
        }
        return v;
    }

    public void setCharsAt(int slot, char[] v) {
        for (int i = 0; i < v.length; i++) {
            charBuffer().put(slot++, v[i]);
        }
    }

    public char[] getCharsAt(int slot, char[] v) {
        for (int i = 0; i < v.length; i++) {
            v[i] = charBuffer().get(slot++);
        }
        return v;
    }

    public void setIntsAt(int slot, int[] v) {
        for (int i = 0; i < v.length; i++) {
            intBuffer().put(slot++, v[i]);
        }
    }

    public int[] getIntsAt(int slot, int[] v) {
        for (int i = 0; i < v.length; i++) {
            v[i] = intBuffer().get(slot++);
        }
        return v;
    }

    public void setFloatsAt(int slot, float[] v) {
        for (int i = 0; i < v.length; i++) {
            floatBuffer().put(slot++, v[i]);
        }
    }

    public float[] getFloatsAt(int slot, float[] v) {
        for (int i = 0; i < v.length; i++) {
            v[i] = floatBuffer().get(slot++);
        }
        return v;
    }

    /**
     * Puts a double at the specified slot (8-byte offset).
     * May throw an {@link UnsupportedOperationException}
     */
    public void setDoublesAt(int slot, double[] v) {
        for (int i = 0; i < v.length; i++) {
            doubleBuffer().put(slot++, v[i]);
        }
    }

    /**
     * Retrieves the long at the specified slot (8-byte offset).
     * May throw an {@link UnsupportedOperationException}
     */
    public double[] getDoublesAt(int slot, double[] v) {
        for (int i = 0; i < v.length; i++) {
            v[i] = doubleBuffer().get(slot++);
        }
        return v;
    }

    /**
     * Retrieves the long at the specified slot (8-byte offset).
     */
    public long getLongAt(int slot) {
        return longBuffer().get(slot);
    }

    /**
     * Puts a long at the specified slot (8-byte offset).
     */
    public void setLongAt(int slot, long v) {
        longBuffer().put(slot, v);
    }

    //----------------------------------------------------------------------
    // Internals only below this point
    //

    private final FloatBuffer floatBuffer() {
        if (fb == null) {
            fb = bb.asFloatBuffer();
        }
        return fb;
    }

    private final IntBuffer intBuffer() {
        if (ib == null) {
            ib = bb.asIntBuffer();
        }
        return ib;
    }

    private final ShortBuffer shortBuffer() {
        if (sb == null) {
            sb = bb.asShortBuffer();
        }
        return sb;
    }

    private final LongBuffer longBuffer() {
        if (lb == null) {
            lb = bb.asLongBuffer();
        }
        return lb;
    }

    private final DoubleBuffer doubleBuffer() {
        if (db == null) {
            db = bb.asDoubleBuffer();
        }
        return db;
    }

    private final CharBuffer charBuffer() {
        if (cb == null) {
            cb = bb.asCharBuffer();
        }
        return cb;
    }
}