com.sun.scenario.effect.impl.BufferUtil Maven / Gradle / Ivy
/*
* Copyright (c) 2008, 2014, 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 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.
*/
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.
*/
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.
*/
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.
*/
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.
*/
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.
*/
public static ShortBuffer newShortBuffer(int numElements) {
ByteBuffer bb = newByteBuffer(numElements * SIZEOF_SHORT);
return bb.asShortBuffer();
}
}