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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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,
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package com.sun.scenario.effect.impl;

import java.lang.reflect.Method;
import java.nio.ByteBuffer;
import java.nio.DoubleBuffer;
import java.nio.FloatBuffer;
import java.nio.IntBuffer;
import java.nio.ShortBuffer;
import java.security.AccessController;
import java.security.PrivilegedExceptionAction;

Utility routines for dealing with direct buffers.
/** * Utility routines for dealing with direct buffers. */
public class BufferUtil { public static final int SIZEOF_BYTE = 1; public static final int SIZEOF_SHORT = 2; public static final int SIZEOF_INT = 4; public static final int SIZEOF_FLOAT = 4; public static final int SIZEOF_DOUBLE = 8; // NOTE that this work must be done reflectively at the present time // because this code must compile and run correctly on both CDC/FP // and Java SE. The ByteOrder class and order() methods are not supported // on CDC; on that platform the initial byte order is the native byte order. private static boolean isCDCFP; private static Class byteOrderClass; private static Object nativeOrderObject; private static Method orderMethod; private BufferUtil() { } public static void nativeOrder(ByteBuffer buf) { if (!isCDCFP) { try { if (byteOrderClass == null) { byteOrderClass = (Class) AccessController.doPrivileged( (PrivilegedExceptionAction) () -> Class.forName("java.nio.ByteOrder", true, null)); orderMethod = ByteBuffer.class.getMethod("order", new Class[]{byteOrderClass}); Method nativeOrderMethod = byteOrderClass.getMethod("nativeOrder", (Class[])null); nativeOrderObject = nativeOrderMethod.invoke(null, (Object[])null); } } catch (Throwable t) { // Must be running on CDC / FP isCDCFP = true; } if (!isCDCFP) { try { orderMethod.invoke(buf, new Object[]{nativeOrderObject}); } catch (Throwable t) { } } } }
Allocates a new direct ByteBuffer with the specified number of elements. The returned buffer will have its byte order set to the host platform's native byte order.
/** * Allocates a new direct ByteBuffer with the specified number of * elements. The returned buffer will have its byte order set to * the host platform's native byte order. */
public static ByteBuffer newByteBuffer(int numElements) { ByteBuffer bb = ByteBuffer.allocateDirect(numElements); nativeOrder(bb); return bb; }
Allocates a new direct DoubleBuffer with the specified number of elements. The returned buffer will have its byte order set to the host platform's native byte order.
/** * Allocates a new direct DoubleBuffer with the specified number of * elements. The returned buffer will have its byte order set to * the host platform's native byte order. */
public static DoubleBuffer newDoubleBuffer(int numElements) { ByteBuffer bb = newByteBuffer(numElements * SIZEOF_DOUBLE); return bb.asDoubleBuffer(); }
Allocates a new direct FloatBuffer with the specified number of elements. The returned buffer will have its byte order set to the host platform's native byte order.
/** * Allocates a new direct FloatBuffer with the specified number of * elements. The returned buffer will have its byte order set to * the host platform's native byte order. */
public static FloatBuffer newFloatBuffer(int numElements) { ByteBuffer bb = newByteBuffer(numElements * SIZEOF_FLOAT); return bb.asFloatBuffer(); }
Allocates a new direct IntBuffer with the specified number of elements. The returned buffer will have its byte order set to the host platform's native byte order.
/** * Allocates a new direct IntBuffer with the specified number of * elements. The returned buffer will have its byte order set to * the host platform's native byte order. */
public static IntBuffer newIntBuffer(int numElements) { ByteBuffer bb = newByteBuffer(numElements * SIZEOF_INT); return bb.asIntBuffer(); }
Allocates a new direct ShortBuffer with the specified number of elements. The returned buffer will have its byte order set to the host platform's native byte order.
/** * Allocates a new direct ShortBuffer with the specified number of * elements. The returned buffer will have its byte order set to * the host platform's native byte order. */
public static ShortBuffer newShortBuffer(int numElements) { ByteBuffer bb = newByteBuffer(numElements * SIZEOF_SHORT); return bb.asShortBuffer(); } }