新手小白参考网上教程学习的socket使用，代码几乎雷同老师写的就可以运行我的就会出问题，connect()方法正确可用，但是send()方法不能用，会提示如图空指针异常，但是我真的找不到是哪里的问题，求大神指点。困扰两天了 茶不思饭不想。（由于提问字数问题导包部分代码没有粘过来）
我用Broadcast在一个activity中监听到操作后广播消息过来然后触发java类里面的方法，触发到connect()就可以运行，但是触发send()方法就报错空指针异常。大神指点，拜托了。
public class Sockets extends BroadcastReceiver{
Socket socket= null;
BufferedWriter writer= null;
BufferedReader reader = null;
PrintWriter testPrintWriter = null;
String Massage = null;
public void connect(){
AsyncTask read = new AsyncTask() {
@Override
protected Void doInBackground(Void... arg0) {
try {
socket = new Socket("10.10.74.75",59671);
writer = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
publishProgress("@success");
} catch (UnknownHostException e1) {
System.out.println("连接失败！");
} catch (IOException e1) {
System.out.println("连接失败！");
}
try {
String line;
while ((line = reader.readLine())!=null) {
publishProgress(line);
}
} catch (Exception e) {
}
return null;
}
@Override
protected void onProgressUpdate(String... values) {
if (values[0].equals("@success")) {
System.out.println(">>>>>>>>>>>>>>>"+values[0]);
}
Massage = values[0];
super.onProgressUpdate(values);
}
};
read.execute();
}
public void send(String massageSend) {
try {
writer.write(massageSend+"\n");//+
writer.flush();
} catch (IOException e) {
e.printStackTrace();
}
}
@Override
public void onReceive(Context arg0, Intent arg1) {
connect();
send(arg1.getStringExtra("massage"));
}
}
