21157 - VictoriaBrown/MyProgrammingLab_Ch10 GitHub Wiki

QUESTION:

All phones must have a way of making and then terminating a connection to the phone network; however the exact procedure for doing so depends upon the nature of the phone (e.g. landline, cell phone, satellite phone). Write a abstract class , Phone, that contains a string instance variable , phoneNumber, a constructor that accepts a string parameter initializing the instance variable , an accessor method , getPhoneNumber, that returns the phoneNumber, a toString method that return the phoneNumber in the form #(phoneNumber), and two abstract methods : a boolean -valued method named createConnection that returns a boolean and accepts an reference to an object of type Network, and a void-returning method , closeConnection, that accepts no parameters

CODE:

public abstract class Phone {

	// Instance variable:
	private String phoneNumber;

	// Constructor:
	public Phone(String phoneNumber) {
		this.phoneNumber = phoneNumber;
	}

	// Return phone number (get method):
	public String getPhoneNumber() {
		return phoneNumber;
	}

	// Return phone number in form of #(phoneNumber) toString method:
	public String toString() {
		return "#(" + getPhoneNumber() + ")";
	}

	// Abstract method:
	public abstract boolean createConnection(Network object);

	// Abstract method:
	public abstract void closeConnection();
}