Question

In a project named 'DogApplication', create a class called 'Dog'

1. declare two instance variables in 'Dog' :

name (String type)

age (int type)

2. declare the constructor for the 'Dog' class that takes two input parameters and uses these input parameters to initialize the instance variables

3. create another class called 'Driver' and inside the main method, declare two variables of type 'Dog' and call them 'myDog' and 'yourDog', then assign two variables to two instance of 'Dog' with any values of your choice for name and age.

4. go back to 'Dog' class and implement the 'toString' method and then call this method from 'Driver' to print the dogs' info.

this is what I have so far:

for Dog

public class Dog
{
   //instance variables
   private String name;
   private int age;
  
  
   //constructor, takes the instance variable and binds to constructor
   public Dog(String dogName, int dogAge) //has the same name as the class
   {
       name = dogName;               //assigns the instance variables which has no value to the constructor parameters
       age = dogAge;
      
      
   }
  
   public String toString()
   {
       String Dog = "";
      
       Dog += this.name + "\t";
       Dog += this.age;
       return Dog;
   }
  
  
  
}

and for Driver:

public class Driver
{
   public static void main (String [] args)
   {
       Dog myDog = new Dog ("Gino", 6);
       Dog yourDog = new Dog ("Amie",7);
      
       System.out.println(Dog.name);
       System.out.println(Dog.age);
   }
  
  
}

I'm not sure if I did this right. Can you explain?

Answer 1

//File1
//Dog.java
public class Dog
{
  private String name;
  private String breed;
  private int age;

  public Dog() {
  }

  public Dog(String name, int age) {
    this.name = name;
    this.age = age;
  }

  // Accessors and Mutators

  public String getName() {
    return name;
  }

  public void setName(String name) {
    this.name = name;
  }

  public String getBreed() {
    return breed;
  }

  public void setBreed(String breed) {
    this.breed = breed;
  }

  public int getAge() {
    return age;
  }

  public void setAge(int age) {
    this.age = age;
  }

  // create these for each of the three instance variables
   /* your code goes here */


  public boolean equals(Object o) {
    if (this == o) return true;
    if (!(o instanceof Dog)) return false;

    Dog dog = (Dog) o;

    if (age != dog.age) return false;
    if (name != null ? !name.equals(dog.name) : dog.name != null) return false;
    return breed != null ? breed.equals(dog.breed) : dog.breed == null;
  }


  public void writeOutput()
  {
    // print out the Dog's characteristics as shown above
    System.out.println("Name: "+getName()+" Breed: "+getBreed()+" Age in calendar years: "+getAge()+" Age in human years: "+getAgeInHumanYears());

       /* your code goes here */

  }

  public int getAgeInHumanYears()
  {
    // implement this method
    return getAge()*2;
   /* your code goes here */

  }

  public String toString() {
    return "Dog{" +
      "name='" + name + ''' +
      ", breed='" + breed + ''' +
      ", age=" + age +
      '}';
  }
}

=======================================================

//File2
//Driver.java
public class Driver{
    public static void main(String[] args)
    {
      Dog myDog = new Dog("Balto",8);
      myDog.setBreed("Siberian Husky");
      System.out.println(myDog);

      Dog yourDog = new Dog("Scooby",42);
      yourDog.setBreed("Great Dane");
      System.out.println(yourDog);
    }
}

=======================================================

Dog{name='Balto', breed='Siberian Husky', age=8}
Dog{name='Scooby', breed='Great Dane', age=42}