1. 将字符串转化成字节，并进行ASCII编码

Entity.getDeviceName().getBytes("US-ASCII");

2. Java拷贝byte数组

System.arraycopy(Recvtemp, DeviceNameLen + 1 + timeStampLen + 1 + 1 + FileNameLen +1 + 1, Entity.getFileByteArr(), 0, FileLen);

3. Java发送byte数组

byte[] byteArray = serializeMessage.Serializer(message);

Socket s = new Socket("192.168.7.37", 8885);

OutputStream os = s.getOutputStream();

os.write(byteArray);

4. 网络操作必须开新的线程，不能够在主线程里操作

new Thread(){

public void run(){

try{

sendHeartBeat();

} catch (Exception e) {

e.printStackTrace();

}

}

}.start();