Computer Programming Stuff

[computerprogrammingstuff]

Methods for Scanner Objects

[computerprogrammingstuff]

The result when the previous program is executed.

[computerprogrammingstuff]

2.2 Reading Input from the Console

import java.util.Scanner; // Scanner is in the java.util package

public class ComputeAreaWithConsoleInput 

{

public static void main(String[] args)

{

// Create a Scanner object

Scanner input = new Scanner(System.in);

// Prompt the user to enter a radius

System.out.print("Enter a number for radius: ");

double radius = input.nextDouble();

// Compute area

double area = radius * radius * 3.14159;

// Display results

System.out.println("The area for the circle of radius " + 

 radius + " is " + area);

  }

}

[computerprogrammingstuff]

This is the result of the previous program being executed.

[computerprogrammingstuff]

ComputeArea.java

public class ComputeArea 

{

    public static void main(String[] args)

    {

    double radius; // Declares radius

    double area; // Declares area

    radius = 20;

    area = radius * radius * 3.14159;

    // Display results

    System.out.println("The area for the circle of radius " +

     radius + " is " + area);

    }

}

[computerprogrammingstuff]

This is the result of the program being executed from the previous post.

[computerprogrammingstuff]

WelcomeInMessageDialogBoxAlt.java

/*This application program displays Welcome to Java!

 *in a message dialog box.

 */

 import javax.swing.JOptionPane;

 public class WelcomeInMessageDialogBoxAlt

 {

      public static void main(String[] args)

      {

      // Diplays Welcome to Java! in a message dialog box

      JOptionPane.showMessageDialog(null,

      "Welcome to Java!",

      "Display Message",

      JOptionPane.INFORMATION_MESSAGE);

     }

 }

[computerprogrammingstuff]

This is the result when the program in the previous post is executed.

[computerprogrammingstuff]

WelcomeInMessageDialogBox.java 1.4

/*This application program displays Welcome to Java!

 *in a message dialog box.

 */

 import javax.swing.JOptionPane;

   public class WelcomeInMessageDialogBox

 {

      public static void main(String[] args)

      {

      // Diplays Welcome to Java! in a message dialog box

      JOptionPane.showMessageDialog(null, "Welcome to Java!");

      }

 }

[computerprogrammingstuff]

Computing an Expression in Java 1.3

public class ComputeExpression

{

    public static void main(String[] args)

    {

    System.out.println((10.5 + 2 * 3) / (45 - 3.5));

    }

}

// This is the answer you get: 0.39759036144578314

[computerprogrammingstuff]

First Java Program 1.1

public class Welcome

{

    public static void main(String[] args)

    {

    // Display message Welcome to Java! on the console

    System.out.println("Welcome to Java!");

    }

}