org.nd4j.common.util.NioUtil Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2015-2018 Skymind, Inc.
*
* This program and the accompanying materials are made available under the
* terms of the Apache License, Version 2.0 which is available at
* https://www.apache.org/licenses/LICENSE-2.0.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
* SPDX-License-Identifier: Apache-2.0
******************************************************************************/
package org.nd4j.common.util;
import java.nio.*;
/**
* NioUtils for operations on
* nio buffers
* @author Adam Gibson
*/
public class NioUtil {
private NioUtil() {}
public enum BufferType {
INT, FLOAT, DOUBLE
}
/**
* Copy from the given from buffer
* to the to buffer at the specified
* offsets and strides
* @param n
* @param bufferType
* @param from the origin buffer
* @param fromOffset the starting offset
* @param fromStride the stride at which to copy from the origin
* @param to the destination buffer
* @param toOffset the starting point
* @param toStride the to stride
*/
public static void copyAtStride(int n, BufferType bufferType, ByteBuffer from, int fromOffset, int fromStride,
ByteBuffer to, int toOffset, int toStride) {
// TODO: implement shape copy for cases where stride == 1
ByteBuffer fromView = from;
ByteBuffer toView = to;
fromView.order(ByteOrder.nativeOrder());
toView.order(ByteOrder.nativeOrder());
switch (bufferType) {
case INT:
IntBuffer fromInt = fromView.asIntBuffer();
IntBuffer toInt = toView.asIntBuffer();
for (int i = 0; i < n; i++) {
int put = fromInt.get(fromOffset + i * fromStride);
toInt.put(toOffset + i * toStride, put);
}
break;
case FLOAT:
FloatBuffer fromFloat = fromView.asFloatBuffer();
FloatBuffer toFloat = toView.asFloatBuffer();
for (int i = 0; i < n; i++) {
float put = fromFloat.get(fromOffset + i * fromStride);
toFloat.put(toOffset + i * toStride, put);
}
break;
case DOUBLE:
DoubleBuffer fromDouble = fromView.asDoubleBuffer();
DoubleBuffer toDouble = toView.asDoubleBuffer();
for (int i = 0; i < n; i++) {
toDouble.put(toOffset + i * toStride, fromDouble.get(fromOffset + i * fromStride));
}
break;
default:
throw new IllegalArgumentException("Only floats and double supported");
}
}
}