Appendix | Java Fundamentals

Lesson 1: Introduction to Java

Activity 1: Printing the Results of Simple Arithmetic Operations

Solution:

Create a class named Operations as follows:
```
public class Operations
{
```

Within main(), print a sentence describing the operation on the values you will be performing along with the result:

    public static void main(String[] args) {
        System.out.println("The sum of 3 + 4 is " + (3 + 4));
        System.out.println("The product of 3 + 4 is " + (3 * 4));
    }
}

The output will be as follows:

The sum of 3 + 4 is 7
The product of 3 + 4 is 12

Activity 2: Reading Values from the User and Performing Operations Using the Scanner Class.

Solution:

Right-click the src folder and select New | Class.
Enter ReadScanner as the class name, and then click OK.
Import the java.util.Scanner package:
```
import java.util.Scanner;
```

In the main() enter the following:

public class ReadScanner
{
    static Scanner sc = new Scanner(System.in);
  public static void main(String[] args) {
    System.out.print("Enter a number: ");
    int a = sc.nextInt();
    System.out.print("Enter 2nd number: ");
    int b = sc.nextInt();
    System.out.println("The sum is " + (a + b) + ".");

    }
}

Run the main program.

The output will be as follows:

Enter a number: 12                                                                                                             
Enter 2nd number: 23
The sum is 35.

Activity 3: Calculating the Percent Increase or Decrease of Financial Instruments

Solution:

Right-click the src folder and select New | Class.
Enter StockChangeCalculator as the class name, and then click OK.
Import the java.util.Scanner package:
```
import java.util.Scanner;
```

In the main() enter the following:

public class StockChangeCalculator{
static Scanner sc = new Scanner(System.in);
public static void main(String[] args) {
    System.out.print("Enter the stock symbol: ");
    String symbol = sc.nextLine();
    System.out.printf("Enter %s's day 1 value: ", symbol);
    double day1 = sc.nextDouble();
    System.out.printf("Enter %s's day 2 value: ", symbol);
    double day2 = sc.nextDouble();
    double percentChange = 100 * (day2 - day1) / day1;
    System.out.printf("%s has changed %.2f%% in one day.", symbol, percentChange);
}
}

Run the main program.

The output should be similar to:

Enter the stock symbol: AAPL                                                                                                             
Enter AAPL's day 1 value: 100                                                                                                           
Enter AAPL's day 2 value: 91.5                                                                                                           
AAPL has changed -8.50% in one day.

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Java Fundamentals

By : Gazihan Alankus , Rogério Theodoro de Brito , Basheer Ahamed Fazal , Isola, Miles Obare

Java Fundamentals

By: Gazihan Alankus , Rogério Theodoro de Brito , Basheer Ahamed Fazal , Isola, Miles Obare

Overview of this book

Lesson 1: Introduction to Java

Activity 1: Printing the Results of Simple Arithmetic Operations

Activity 2: Reading Values from the User and Performing Operations Using the Scanner Class.

Activity 3: Calculating the Percent Increase or Decrease of Financial Instruments

Java Fundamentals

By : Gazihan Alankus , Rogério Theodoro de Brito , Basheer Ahamed Fazal , Isola, Miles Obare

Java Fundamentals

By: Gazihan Alankus , Rogério Theodoro de Brito , Basheer Ahamed Fazal , Isola, Miles Obare

Overview of this book

Lesson 1: Introduction to Java

Activity 1: Printing the Results of Simple Arithmetic Operations

Activity 2: Reading Values from the User and Performing Operations Using the Scanner Class.

Activity 3: Calculating the Percent Increase or Decrease of Financial Instruments

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