例子
short size = 1234;
byte[] payload = {12,43, 55,123, 11, 55};
byte [] shortSize = ByteBuffer.allocate(2).putShort(size).array();
byte[] entirePayload = new byte[shortSize.length+payload.length];
System.arraycopy(shortSize, 0, entirePayload, 0, 2);
System.arraycopy(payload, 0, entirePayload, 2, payload.length);
这是 Java 系统调用是否有根本原因?