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Command Line Arguments in Java

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Command Line Arguments in Java

Command Line Arguments in Java: state the definition in one sentence. For Command Line Arguments in Java, know the key keywords / API types involved.

Be ready with one tiny runnable Command Line Arguments in Java example.

Mention one common Command Line Arguments in Java mistake and the fix.

Write one tiny example for Command Line Arguments. Compile, print one result, and say the output out loud before you type.

Use Command Line Arguments 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. Command Line Arguments in Java — output: 20. Scanner reads 12 and 8 from a string — same as typing in CMD, but this Main always runs. Start from main, go line by line, and stop at each print. That output is the proof for Command Line Arguments.

Exam tip

Explain Command Line Arguments in Java as: definition → why → one code idea.

Example

import java.util.Scanner;
public class Main {
  public static void main(String[] args) {
    Scanner sc = new Scanner("12 8");
    int a = sc.nextInt();
    int b = sc.nextInt();
    System.out.println(a + b);
    sc.close();
  }
}

Command Line Arguments in Java — output: 20. Scanner reads 12 and 8 from a string — same as typing in CMD, but this Main always runs.

Short notes

DefCommand Line Arguments is a Java idea you should explain with one small example.
RuleKnow the keyword / API used for Command Line Arguments. Type a tiny Main and print one result.
RememberFor Command Line Arguments, say the output before you code.
TrapCommand Line Arguments — only memorising the heading. No example, no trap.
Define Command Line Arguments in Java
Key keyword / API

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner("12 8"); int a = sc.nextInt(); int b = sc.nextInt(); System.out.println(a + b); sc.close(); } }

Command Line Arguments in Java

Example

Short notes

Questions

Command Line Arguments in Java

Example

Short notes

Questions