Java Byte Array Copy memcpy(Object to, Object from, int size)

Description

MEMORY

License

Open Source License

Declaration

public static void memcpy(Object to, Object from, int size) 

Method Source Code

//package com.java2s;
/*******************************************************************************
 * The MIT License (MIT)//  w  w  w. j a  v a 2 s . c  o m
 * 
 * Copyright (c) 2016 Dalibor Drgo? <emptychannelmc@gmail.com>
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 ******************************************************************************/

import java.lang.reflect.Field;

import sun.misc.Unsafe;

public class Main {
    protected static Unsafe unsafe;

    /*** MEMORY ***/

    public static void memcpy(Object to, Object from, int size) {
        System.arraycopy(from, 0, to, 0, size);
    }

    public static void memcpy(Object to, int posto, Object from, int posfrom, int size) {
        System.arraycopy(from, posfrom, to, posto, size);
    }

    public static void memcpy(long to, long from, long sz) {
        getUnsafe().copyMemory(from, to, sz);
    }

    public static Unsafe getUnsafe() {
        if (unsafe == null) {
            Class<?> clz = Unsafe.class;
            Field[] fields = clz.getDeclaredFields();
            for (int i = 0, n = fields.length; i < n; i++) {
                Field f = fields[i];
                if (!f.getType().equals(Unsafe.class)) {
                    continue;
                }
                try {
                    f.setAccessible(true);
                    Unsafe unf = (Unsafe) f.get(null);
                    if (unf != null) {
                        return (unsafe = unf);
                    }
                } catch (Throwable t) {
                }
            }
        }
        return unsafe;
    }
}

Related

1. copyBytesToString(byte[] src, int arg1, int arg2)
2. copyBytesWithin(byte[] bytes, int target, int start, int end)
3. memcpy(byte[] dest, int doff, byte[] src, int soff, int len)
4. memcpy(byte[] destBytes, byte[] srcBytes, int numBytes)
5. memcpy(byte[] dst, int dst_offset, byte[] src, int src_offset, int length)