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Java Exception Handling MCQ Test

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Scanning and Formatting

 Here are some notes on scanning and formatting in Java I/O with examples:

1. Scanning (Input):

   - Scanning involves reading input from different sources like the keyboard, files, or network connections.

   - Java provides the `Scanner` class in the `java.util` package to facilitate scanning.


   Example:

   import java.util.Scanner;

   public class ScannerExample {

       public static void main(String[] args) {

           Scanner scanner = new Scanner(System.in);

           System.out.print("Enter your name: ");

           String name = scanner.nextLine();

           System.out.println("Hello, " + name + "!");

           scanner.close();

       }

   }



2. Formatting (Output):

   - Formatting is the process of presenting data in a specific way, such as aligning text, setting precision for floating-point numbers, etc.

   - The `System.out.printf()` method is commonly used for formatted output in Java I/O.


   Example:


   public class FormattingExample {

       public static void main(String[] args) {

           double price = 19.99;

           int quantity = 5;

           System.out.printf("Total cost: $%.2f%n", price * quantity);

       }

   }



   Explanation:

   - In the `printf()` method, `%f` is a format specifier for floating-point numbers, and `.2` specifies two decimal places.

   - `%n` is a platform-independent newline character.


These examples demonstrate basic usage of scanning for input and formatting for output in Java I/O. They can be expanded upon to suit various input and output requirements in Java programs.

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