Reputation: 13
i try to open a TCP Socket in Java and sent a GET request to a server (www.abc.net.au) and print the response to the console.
Client code:
import java.util.Scanner;
import java.net.InetAddress;
import java.net.SocketAddress;
import java.net.InetSocketAddress;
import java.net.Socket;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
public class Client {
public static void main(String[] args) throws Exception{
Scanner sc;
String addressString;
int port =80;
int timeoutMs = 30000;
String temp;
//Read address from commandline
sc =new Scanner(System.in);
System.out.print("Adresse: ");
addressString = sc.next();
sc.close();
//Open socket
InetAddress addr = InetAddress.getByName(addressString);
SocketAddress sockaddr = new InetSocketAddress(addr, port);
Socket socket = new Socket();
//Connection timeout
socket.connect(sockaddr,timeoutMs);
System.out.println( socket.getPort() +"\n");
//Define input/output
BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
PrintWriter pw = new PrintWriter(socket.getOutputStream(), true);
//Send GET request
pw.print("GET / HTTP/1.1\r\n");
pw.print("Host: "+ addressString +"\r\n\r\n");
while((temp=br.readLine())!=null){
System.out.println(temp);
}
//Close Input/Output and Socket
pw.close();
br.close();
socket.close();
}
}
The code seems to work till it reaches the while and afterwards i get:
HTTP/1.0 408 Request Time-out
Server: AkamaiGHost
Mime-Version: 1.0
Date: Sun, 07 Oct 2018 15:36:40 GMT
Content-Type: text/html
Content-Length: 218
Expires: Sun, 07 Oct 2018 15:36:40 GMT
<HTML><HEAD>
<TITLE>Request Timeout</TITLE>
</HEAD><BODY>
<H1>Request Timeout</H1>
The server timed out while waiting for the browser's request.<P>
Reference #2.3d5b6068.1538926600.0
</BODY></HTML>
Process finished with exit code 0
I don't understand what causes the problem, already looked for answers on stackoverflow, java2s and a book i got at home. Trying other pages often ends just with:
Process finished with exit code 0
and nothing else.
Any idea what's missing/incorrect with my request?
Appriciate every hint.
Upvotes: 1
Views: 4329
Reputation: 24219
PrintWriter
has internal buffer which is used to store data, so when you're calling print
- nothing is sent to server
From https://docs.oracle.com/javase/7/docs/api/java/io/PrintWriter.html
Unlike the PrintStream class, if automatic flushing is enabled it will be done only when one of the println, printf, or format methods is invoked, rather than whenever a newline character happens to be output.
So, you can either use of these methods instead of print
or just call flush
explicitely:
pw.print("GET / HTTP/1.1\r\n");
pw.print("Host: " + addressString + "\r\n\r\n");
pw.flush(); // actually send data to server
Upvotes: 1