Question

Writing Classes I
Write a Java program containing two classes: Dog and a driver class Kennel.

A dog consists of the following information:
• An integer age.
• A string name. If the given name contains non-alphabetic characters, initialize to Wolfy.
• A string bark representing the vocalization the dog makes when they ‘speak’.
• A boolean representing hair length; true indicates short hair.
• A float weight representing the dog’s weight (in pounds).
• An enumeration representing the type of tail (LONG, SHORT, NONE).

A dog consists of the following methods.
• A default constructor.
• A constructor that takes a name as argument.
• A method private boolean validName(String) that returns true / false whether the given name contains non-alphabetic characters.
• humanAge that computes and returns the age of the dog in “human years.”
• speak returns the dog’s bark.

Each constructor should initialize all attributes to reasonable initial values.

The main method in the Kennel class should create several dogs with each constructor and output
their instance data using toString.

Answer 1

Code:

//Class Dog
class Dog{
private int age; //An integer age.
private String name,bark; //A string name and a string bark representing the vocalization the dog makes when they ‘speak’.
private boolean hairlen; //A boolean representing hair length; true indicates short hair.
private float weight; // A float weight representing the dog’s weight (in pounds).
public static enum tail{ LONG, SHORT, NONE };
private tail t; //An enumeration representing the type of tail (LONG, SHORT, NONE).
  
//A default constructor.
public Dog()
{
age=0;
name="Wolfy";
bark="owww";
hairlen=false;
weight=0;
t = tail.NONE;
  
}
  
//A constructor that takes a name as argument.
public Dog(int age,String name,String bark,float weight,boolean hairlen,tail t)
{
if(validName(name))
this.name=name;
else //If the given name contains non-alphabetic characters, initialize to Wolfy.
this.name="Wolfy";

this.age=age;   
this.bark=bark;
this.hairlen=hairlen;
this.weight=weight;
this.t = t;
  
}
  
//A method private boolean validName(String) that returns true / false whether the given name contains non-alphabetic characters.
private boolean validName(String name)
{
for(int i=0;i<name.length();i++)
{
//System.out.println(Character.isLetter(name.charAt(i)));
if(!Character.isLetter(name.charAt(i)))
return false;
}

return true;
}
  
//Method that computes and returns the age of the dog in “human years.”
public int humanAge()
{
return 7*age;
}

//Method that returns the dog’s bark.
public String speak()
{
return bark;
}

//toString to display dog info
public String toString()
{
return "Name: "+name+", age: "+age+", bark: "+speak()+", weight: "+weight;
}
}

// Kennel class
public class Kennel {
  
//Main() method
public static void main(String[] args) {
  
//Creating multiple Dog class objects
Dog d1,d2,d3,d4,d5;
d1 = new Dog(10,"Tommy","Wuff",10,true,Dog.tail.NONE);
d2 = new Dog(14,"Ralph","Purr",40,false,Dog.tail.LONG);
d3 = new Dog(12,"Buck","Oww",14,false,Dog.tail.SHORT);
d4 = new Dog(5,"89kl","Huff",16,true,Dog.tail.NONE);
d5 = new Dog(12,"John","Puff",23,false,Dog.tail.SHORT);
  
System.out.println(d1);
System.out.println(d2);
System.out.println(d3);
System.out.println(d4);
System.out.println(d5);
  

}
  
}

Sample Run: