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URL class

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URL class

java.net covers sockets, URLs, addresses. Socket = endpoint for TCP communication.

URL/URLConnection fetch remote resources.

Always handle IOException.

Write one tiny example for URL class. Compile, print one result, and say the output out loud before you type.

Use URL class 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. URL class — 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 URL class.

Exam tip

Client socket needs host + port.

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());
  }
}

URL class — prints local machine host name and IP — basic networking API.

Short notes

DefURL class is a Java idea you should explain with one small example.
RuleKnow the keyword / API used for URL class. Type a tiny Main and print one result.
RememberFor URL class, say the output before you code.
TrapURL class — only memorising the heading. No example, no trap.
Socket = endpoint
URL for resources

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()); } }

URL class

Example

Short notes

Questions

URL class

Example

Short notes

Questions