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How to test the backlog function of ServerSocket class

Hi,
I have written a client server simple Java Application.
It uses Java ServerSocket Class
int backLog = 1;

ServerSocket serverSocket = new ServerSocket(port, backLog);

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As per my understanding the server will accept incoming request and return the response.
And during this request response cycle if server is in the middle of processing an earlier request. It will put that request in a queue. The length of the queue is defined by backLog. And if the number of request exceeds this backLog then it will throw some exception for any further request.

Hope the above understanding is correct.
Now i put backlog = 1 purposefully so as to see the case where the exception actually occurs. But since servers are too fast in responding. How do i achieve this.
Is there any utility which can help me sending multiple simultaneous request to the server.

Thanks

Rohit Bajaj

ASKER

I noticed one behavior which i dont entirely understand. Here is the error that server threw :

Server read error
java.net.SocketException: Connection reset
   at java.base/java.net.SocketInputStream.read(SocketInputStream.java:186)
   at java.base/java.net.SocketInputStream.read(SocketInputStream.java:140)
   at java.base/sun.nio.cs.StreamDecoder.readBytes(StreamDecoder.java:284)
   at java.base/sun.nio.cs.StreamDecoder.implRead(StreamDecoder.java:326)
   at java.base/sun.nio.cs.StreamDecoder.read(StreamDecoder.java:178)
   at java.base/java.io.InputStreamReader.read(InputStreamReader.java:185)
   at java.base/java.io.BufferedReader.fill(BufferedReader.java:161)
   at java.base/java.io.BufferedReader.readLine(BufferedReader.java:326)
   at java.base/java.io.BufferedReader.readLine(BufferedReader.java:392)
   at Worker.run(JokeServer.java:28)

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I had two programs written like :

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.net.Socket;

public class Test1 {
    public static void main(String[] args) {
        Socket socket;
        BufferedReader bufferedReader;
        PrintStream printStream;
        String textFromServer;
        try {
            socket = new Socket("localhost", 4545);
            bufferedReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            printStream = new PrintStream(socket.getOutputStream());
            printStream.flush();
            for (int i = 0; i <= 1; i++) {
                textFromServer = bufferedReader.readLine();
                if (textFromServer != null)
                    System.out.println(textFromServer);
            }
        } catch (IOException ioe) {
            System.out.println("Socket error.");
            ioe.printStackTrace();
        }
    }

}

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and

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.net.Socket;

public class Test2 {
    public static void main(String[] args) {
        Socket socket;
        BufferedReader bufferedReader;
        PrintStream printStream;
        String textFromServer;
        try {
            socket = new Socket("localhost", 4545);
            bufferedReader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            printStream = new PrintStream(socket.getOutputStream());
            printStream.flush();
        } catch (IOException ioe) {
            System.out.println("Socket error.");
            ioe.printStackTrace();
        }
    }

}

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Initially i run the server code.
Then i run Test1.java
Till now its fine.
But whenever i run Test2.java
I get that exception.
Also i intentionally didnt closed the socket was thinking that could help me gain understanding of the backlog parameter. But The test2.java still errored out when i changed the backlog to 2.

What could be the reason for this

Thanks