Socket Programming — Java Technical Interview Questions & Answers

Socket Programming

Socket Programming

  • java.net covers sockets, URLs, addresses. Socket = endpoint for TCP communication.
  • URL/URLConnection fetch remote resources.
  • Always handle IOException.
  • Write one tiny example for Socket Programming. Compile, print one result, and say the output out loud before you type.
  • Use Socket Programming only when the problem needs it. Don’t force it into every program. Know one beginner trap.
  • Let's take this on the board with one tiny Main class — no extra files. Socket Programming — prints local machine host name and IP — basic networking API. Start from main, go line by line, and stop at each print. That output is the proof for Socket Programming.

Technical Interview Tip: Client socket needs host + port.

Code Examples for Socket Programming

Example

import java.net.InetAddress;
public class Main {
  public static void main(String[] args) throws Exception {
    InetAddress local = InetAddress.getLocalHost();
    System.out.println(local.getHostName());
    System.out.println(local.getHostAddress());
  }
}

Socket Programming — prints local machine host name and IP — basic networking API.

How to Explain Socket Programming to an Interviewer

What is Socket Programming?

Socket Programming is a Java idea you should explain with one small example. Know the keyword / API used for Socket Programming. Type a tiny Main and print one result. For Socket Programming, say the output before you code.

Why do we use Socket Programming in Java?

Makes the program clearer or safer Socket Programming is a Java idea you should explain with one small example.

Write one small example of Socket Programming.

Show syntax Say what prints

What mistake do beginners make with Socket Programming?

Only the name, no example Socket Programming — only memorising the heading. No example, no trap.

Where is Socket Programming used in a real program?

Day-to-day Java code