我想通過網絡接收圖像,我設置了一個服務器,如下顯示java.lang.NullPointerException的ServerSocket.accept中的()
public class IServerActivity extends Activity {
ServerSocket ss = null;
Bitmap bp ;
Thread myCommsThread = null;
protected static final int MSG_ID = 0x1337;
public static final int SERVERPORT = 6000;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//TextView tv = (TextView) findViewById(R.id.TextView01);
this.myCommsThread = new Thread(new CommsThread());
this.myCommsThread.start();
}
@Override
protected void onStop() {
super.onStop();
try {
// make sure you close the socket upon exiting
ss.close();
} catch (IOException e) {
e.printStackTrace();
}
}
Handler myUpdateHandler = new Handler() {
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_ID:
ImageView iv = (ImageView) findViewById(R.id.imageView01);
iv.setImageBitmap(bp);;
break;
default:
break;
}
super.handleMessage(msg);
}
};
class CommsThread implements Runnable {
public void run() {
Socket s = null;
try {
ss = new ServerSocket(SERVERPORT);
} catch (IOException e) {
e.printStackTrace();
}
while (!Thread.currentThread().isInterrupted()) {
Message m = new Message();
m.what = MSG_ID;
try {
if (s == null)
s = ss.accept();
bp= BitmapFactory.decodeStream(s.getInputStream());
myUpdateHandler.sendMessage(m);
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
但它顯示了在運行時錯誤
java.lang.NullPointerException
E/AndroidRuntime(3047):atExample.IServer.IServerActivity$CommsThread.run(IServerActivity.java:68)
它顯示空指針異常在s = ss.accept();一行。 請幫助我不知道什麼是錯的。
is「ss = new ServerSocket(SERVERPORT);」拋出異常? PLease檢查控制檯是否「e.printStackTrace();」被執行 – 2012-07-09 06:46:50
不,「s = ss.accept();」拋出一個空指針異常。並且是「e.printStackTrace()」被執行。 – Akshay 2012-07-09 06:54:23
請幫我卡在這.. – Akshay 2012-07-09 06:55:06