static long getLongLE(byte[] memory, int index) {
        return (long) memory[index] & 0xff | ((long) memory[index + 1] & 0xff) << 8
               | ((long) memory[index + 2] & 0xff) << 16 | ((long) memory[index + 3] & 0xff) << 24
               | ((long) memory[index + 4] & 0xff) << 32 | ((long) memory[index + 5] & 0xff) << 40
               | ((long) memory[index + 6] & 0xff) << 48 | ((long) memory[index + 7] & 0xff) << 56;
    }
Utility class for heap buffers.

Forked from <a href="https://github.com/netty/netty">Netty</a>.
jraft-core/src/main/java/com/alipay/sofa/jraft/util/HeapByteBufUtil.java