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Scanner class in Java

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Scanner class in Java

Scanner class in Java: state the definition in one sentence. For Scanner class in Java, know the key keywords / API types involved.

Be ready with one tiny runnable Scanner class in Java example.

Mention one common Scanner class in Java mistake and the fix.

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

Use Scanner 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. Scanner class in Java — scanner reads ints from a string source and adds them. Start from main, go line by line, and stop at each print. That output is the proof for Scanner class.

Exam tip

Explain Scanner class 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("10 20");
    System.out.println(sc.nextInt() + sc.nextInt()); // 30
    sc.close();
  }
}

Scanner class in Java — scanner reads ints from a string source and adds them.

Short notes

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

import java.util.Scanner; public class Main { public static void main(String[] args) { Scanner sc = new Scanner("10 20"); System.out.println(sc.nextInt() + sc.nextInt()); // 30 sc.close(); } }

Scanner class in Java

Example

Short notes

Questions

Scanner class in Java

Example

Short notes

Questions