[英]Android Socket Read Problems
我创建了一个连接到Raspberry pi热点的套接字。 我能够成功连接到它并向pi发送一个字符串。 但是,由于我尝试实现读取功能以从pi获取数据,因此遇到了一些问题。
每次我运行while循环或只有一个“ response = myBufRead.readLine()”时,程序都会停顿。
private class StatusCheck extends AsyncTask<Void, Void, Void> {
@Override
protected Void doInBackground(Void... params) {
//debug vibrations and text
if(vibrate) {
Vibrator vib = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);
vib.vibrate(100);
}
try {
InetAddress serverAddr = InetAddress.getByName(SERVER_IP);
Log.d(debugStr, "In initial connect");
mySocket = new Socket(serverAddr, SERVERPORT);
} catch (UnknownHostException e1) {
e1.printStackTrace();
} catch (IOException e1) {
e1.printStackTrace();
} finally {
if (mySocket == null) {
str1 = "Socket became null";
return null;
}
str1 = "Connected";
try {
PrintWriter myPrintWriter = new PrintWriter(mySocket.getOutputStream(), true);
InputStreamReader myInputStreamRead = new InputStreamReader(mySocket.getInputStream());
BufferedReader myBufRead = new BufferedReader(myInputStreamRead);
Log.d(debugStr, "In out created");
myPrintWriter.write(recordName);
Log.d(debugStr, String.valueOf(myBufRead.ready()));
Log.d(debugStr, "About to enter while loop");
while((response = myBufRead.readLine()) != null) {
Log.d(debugStr, "in while loop");
response = myBufRead.readLine();
Log.d(debugStr, String.valueOf(myBufRead.ready()));
Log.d(debugStr, myBufRead.readLine());
Log.d(debugStr, String.valueOf(myBufRead.ready()));
}
Log.d(debugStr, "out of while loop");
myPrintWriter.close();
myInputStreamRead.close();
myBufRead.close();
} catch (IOException e1) {
e1.printStackTrace();
}
try {
mySocket.close();
} catch (IOException e1) {
e1.printStackTrace();
}
return null;
}
}
}
有人知道为什么会这样吗? 任何帮助表示赞赏,谢谢!
BuffereadReader.readLine()
是一种阻塞方法,因此它将等待,并且正如您所说的那样,“阻塞”它的线程,直到它有要读取的内容为止。 从pi写入流后,是否要调用flush()
?
另一个问题可能是readLine()
将等待完整的行,即它将等待直到读取行分隔符为止。 您要从pi发送一个行分隔符吗? 请参见套接字多线程-读取输入流可暂停线程
您可以这样做(假设您正在使用BufferedWriter
,从pi端开始):
bufferedWriter.write(text);
bufferedWriter.newLine();
bufferedWriter.flush();
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.