Question

Part 1 Understand the Problem and Class Design with UML

• The client needs a program to calculate the age of a tuna fish. The program must store the length of the fish in cm, and the weight of the fish in pounds. To calculate the estimated age of the fish in years multiply the length times the weight then divide by 10000. Design a class based on this word problem.

• Testing values are 300 cm length, and 1111.12 pounds.

• Using the word problem above, design a class with the needed fields, one default (no parameter) constructor, and needed methods. Document your design using a detailed UML Class diagram.

• Note: The calculations used in this word problem are fictional.

Part 2 Write the Java code for the class

• Follow your UML class diagram and code the class you designed.
• Use Java coding conventions for identifiers: class, constructor, field, variable, and method names
• Mark fields private, constructor and methods public.
• Select and use appropriate data types for the fields as well as method parameters as needed.
• Comment your code as requested and demonstrated in the course.

Answer 1

Part 1 : UML Class Diagram

Part 2 : Java Code

class Fish
{
    private double length; //in case the length is in decimals
    private double weight; //in case the weight is in decimals
    
    public Fish() //default constructor
    {
        length = 0;
        weight = 0;
    }
    
    public void setLength(double l) // method to set value of private variable length
    {
        length = l;
    }
    
    public void setWeight(double w) // method to set value of private variable weight
    {
        weight = w;
    }
    
    public double getLength() // method to get value of private variable length
    {
        return length;
    }
    
    public double getWeight() // method to get value of private variable weight
    {
        return weight;
    }
    
    public double calcAge()
    {
        double age = length * weight / 10000;
        return age;
    }
    
        public static void main(String[] args) 
        {
                Fish tuna = new Fish(); // initializing and calling constructor
                tuna.setWeight(1111.12);
                tuna.setLength(300);
                System.out.println(tuna.calcAge());
        }
}