1213 Uncc Final Exam - Qs & As

What are the 4 components (concepts) every object-oriented language must have? {Ans: Encapsulation, Data Abstraction, Polymorphism and Inheritence}T/F: The programmer must write a constructor method for each class he/she writes or the class will not compile. {Ans: False}Write the command to compile a source code file named Book.java {Ans: javac Book.java}What type of Exceptions do not require the programmer to write any additional code? {Ans: Unchecked or Run time Exceptions}What is contained in a Java package? {Ans: Classes and Interfaces}Use the following hierarchy to answer 40-43 public abstract class BankAccount public class SavingsAccount extends BankAccount public class CheckingAccount extends BankAccount public class CheckingPlus extends CheckingAccount Which of the following are valid declarations? a) BankAccount bA = new BankAccount( ): b) BankAccount bA = new SavingsAccount( ); c) BankAccount bA = new CheckingPlus( ); d) CheckingAccount bA = new CheckingPlus( ); e) SavingsAccount bA = new CheckingAccount( ); f) CheckingAccount bA = new CheckingPlus( ); g) ChekingPlus bA = new CheckingAccount( ); {Ans: B, C, D, AND F}