我想将数据发送到服务器,然后等待一分钟的答案,然后关闭套接字。
怎么做?
DatagramPacket sendpack = new ......;
socket.send(pack);
DatagramPacket recievepack = new .....;
//wait 1 minute{
socket.recieve(buf);
//wait 1 minute}
socket.close();
答案 0 :(得分:21)
你可以试试这个。根据场景中的需要更改套接字的超时!此代码将发送消息,然后等待接收消息,直到达到超时!
DatagramSocket s;
try {
s = new DatagramSocket();
byte[] buf = new byte[1000];
DatagramPacket dp = new DatagramPacket(buf, buf.length);
InetAddress hostAddress = InetAddress.getByName("localhost");
String outString = "Say hi"; // message to send
buf = outString.getBytes();
DatagramPacket out = new DatagramPacket(buf, buf.length, hostAddress, 9999);
s.send(out); // send to the server
s.setSoTimeout(1000); // set the timeout in millisecounds.
while(true){ // recieve data until timeout
try {
s.receive(dp);
String rcvd = "rcvd from " + dp.getAddress() + ", " + dp.getPort() + ": "+ new String(dp.getData(), 0, dp.getLength());
System.out.println(rcvd);
}
catch (SocketTimeoutException e) {
// timeout exception.
System.out.println("Timeout reached!!! " + e);
s.close();
}
}
} catch (SocketException e1) {
// TODO Auto-generated catch block
//e1.printStackTrace();
System.out.println("Socket closed " + e1);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
答案 1 :(得分:8)
如果您使用的是DatagramSocket或Socket,则可以使用
socket.setSoTimeout(1000);
//the value is in milliseconds
对于任何细节,您应该查看DatagramSocket javadoc或Socket javadoc。
答案 2 :(得分:1)
为了澄清EJP的评论,这就是“缺少break
”导致SocketException的意思。
String group = "224.0.0.0";
int port = 5000;
MulticastSocket recvSock = new MulticastSocket(port);
recvSock.joinGroup(InetAddress.getByName(group));
recvSock.setSoTimeout(1000);
while(true) {
try {
recvSock.receive(in);
} catch (SocketTimeoutException e) {
break; // Closing here would cause a SocketException
}
}
// Move the close() outside the try catch bloock
recvSock.leaveGroup(InetAddress.getByName(group));
recvSock.close();