tutorial_30.java

/**
 * Driver class
 */
class PetStore {
 
 public static void main(String[] args) {

 // create an instance of our Dog class using our three different constructors
 Dog lab1 = new Dog();
 Dog lab2 = new Dog("Mike", "brown", true);
 Dog lab3 = new Dog("Barker");
 
 }
 
}
/**
 * Dog class
 */
class Dog { 
 private String name;
 private String color;
 private int age;
 private double height;
 private boolean male;

 // by default constructor will set everything to null, 0, or false
 public Dog() {
 name = "";
 color = "";
 age = 0;
 height = 0.5;
 male = true;
 }

 public Dog(String n, String c, boolean g) {
 name = n;
 color = c;
 age = 0; // optional because it will automatically set primitive data types to zero
 height = 0.5;
 male = g;
 }

 public Dog(String name) {
 /* need to specify which variable is from your class 
 and which one is the argument using the 'this' keyword
 */
 this.name = name;
 }

}