Java Examples - Screen I/O

Screen I/O in Java is generally done using the `Scanner` class which is a part of the `java.util` package. Here’s a simple Java program example:

import java.util.Scanner;

public class UserInputExample {
    public static void main(String[] args) {
        // Create a Scanner object to read input
        Scanner scanner = new Scanner(System.in);
        
        // Prompt the user to enter a value
        System.out.print("Enter a value: ");
        
        // Read the value entered by the user
        String userInput = scanner.nextLine();
        
        // Output the value to the screen
        System.out.println("You entered: " + userInput);
        
        // Close the scanner object
        scanner.close();
    }
}

An explanation of the example:

**Import Statement**: The `java.util.Scanner` class is imported to facilitate user input.
**Scanner Object**: An instance of `Scanner` is created to read input from the standard input stream, `System.in`.
**Prompting User**: The program prompts the user to enter a value using `System.out.print`.
**Reading Input**: `scanner.nextLine()` is called to read the user’s input as a `String`.
**Displaying Output**: The entered value is then printed to the screen with `System.out.println`.
**Closing Scanner**: It’s good practice to close the `Scanner` object with `scanner.close()` to free up system resources.

Compile and run this program in a Java environment, and it will wait for the user to input a value, and then display the entered value back to the console.

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