Question

I am trying to open a socket connection from my iphone simulator and send a simple NSString to a localhost server I set up with java in port 80.

The problem that I have is that when I write data on the NSOutputStream its not being received by the server until I close the simulator. And then the server receives the data and this exception is thrown java.net.SocketException: Broken pipe

I know is something related with closing the NSOutputStream and flushing, but how can I achieve this in Objective c?

I call the ProtocolCommunication in my initial ViewController like this:

    protocol = [[ProtocolCommunication alloc] init];
    [protocol initNetworkCommunication];
    [protocol sendData];

ProtocolCommunication class (IOS)

@implementation ProtocolCommunication
@synthesize inputStream, outputStream

- (void) initNetworkCommunication {

CFReadStreamRef readStream;
CFWriteStreamRef writeStream;
CFStreamCreatePairWithSocketToHost(NULL, (CFStringRef)@"localhost", 80, &readStream, &writeStream);
inputStream = (NSInputStream *)readStream;
outputStream = (NSOutputStream *)writeStream;
[inputStream setDelegate:self];
[outputStream setDelegate:self];
//do the Looping
[inputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[outputStream scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[inputStream open];
[outputStream open];
NSLog(@"INIT COMPLETE");

}

- (void) sendData {

NSString *response  = @"HELLO from my iphone";
NSData *data = [[NSData alloc] initWithData:[response dataUsingEncoding:NSASCIIStringEncoding]];
[outputStream write:[data bytes] maxLength:[data length]];

}

Java Server

String msgReceived;     
    try {
        ServerSocket serverSocket = new ServerSocket(80);
        System.out.println("RUNNING SERVER");
        while (running) {
            Socket connectionSocket  = serverSocket.accept();
            BufferedReader inFromClient = new BufferedReader(
                    new InputStreamReader(connectionSocket.getInputStream()));
            DataOutputStream outToClient = new DataOutputStream(connectionSocket.getOutputStream());
            msgReceived = inFromClient.readLine();
            System.out.println("Received: " + msgReceived);             
            outToClient.writeBytes("Aloha from server");
            outToClient.flush();
            outToClient.close();
        }

    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

Any Ideas??

Answer 1

I solved it by just adding \n to the NSString like this:

NSString *response  = @"HELLO from my iphone \n"; // This flushes the NSOutputStream so becarefull everyone