Which of the following class members should usually be private?

Which of the following is false?

When must a program explicitly use the this reference?

Static class variables: ..............

Inheritance is also known as the ..............

Using public set methods helps provide data integrity if: .......

A final field should also be declared if it is initialized in its declaration

A constructor cannot...

Which of the following statements is true?

If a method is private, it can be accessed from outside the class directly.

A class constructor must have a return type.

The "static" modifier in Java allows methods and attributes to be accessed without creating an instance of the class.

Overloading a method in Java means creating multiple methods with the same name but different parameter lists.

What is the main goal of encapsulation in object-oriented programming?

The Object class in Java is the default superclass of all classes if no other superclass is specified.

The keyword this is used to refer to the current instance of a class.

Method overloading allows multiple methods to have the same name but different parameters in the same class.

Which of the following methods can access private attributes directly?

What access level does the "protected" modifier grant to a class member?

Which of the following class definitions defines a legal abstract class?

Which of the following statements regarding abstract methods is false?

Suppose A is an abstract class, B is a concrete subclass of A, and both A and B have a no-arg constructor. Which of the following is correct?

Which of the following declares an abstract method in an abstract Java class?

Which of the following statements regarding abstract methods is false?

Instances of ________ are unchecked exceptions.

A Java exception is an instance of ________.

What exception type does the following program throw? public class Test { public static void main(String[] args) { int[] list = new int[5]; System.out.println(list[5]); } }

What is the output of running class Test? public class Test { public static void main(String[] args) { new Circle9(); } } public abstract class GeometricObject { protected GeometricObject() { System.out.print("A"); } protected GeometricObject(String color, boolean filled) { System.out.print("B"); } } public class Circle9 extends GeometricObject { /** No-arg constructor */ public Circle9() { this(10); System.out.print("C"); } /** Construct circle with a specified radius */ public Circle9(double radius) { this(radius, "white", false); System.out.print("D"); } /** Construct a circle with specified radius, filled, and color */ public Circle9(double radius, String color, boolean filled) { super(color, filled); System.out.print("E"); } }

An instance of ________ describes system errors. If this type of error occurs, there is little you can do beyond notifying the user and trying to terminate the program gracefully.

If a class contains at least one abstract method, then it is an abstract class.

A “has-a” relationship is implemented via inheritance.

A superclass’s ____________ members can be accessed in the superclass declaration and in subclass declarations.

Which of the following is a valid method signature?

______________ involves using a superclass variable to invoke methods on superclass and subclass objects, enabling you to develop generic programs.

We can create a “Car” class that has an “is-a” relationship with the “SteeringWheel” and “Brakes” classes.

Methods that are not interface methods and that do not provide implementations must be declared ______________

________ is a form of software reusability in which new classes acquire the members of existing classes and embellish those classes with new capabilities.

Given the following code in a try block. int arr[ ] = new int[7]; arr[10] = 10 / 0; What do you expect to happen if the following catch blocks are included catch(ArrayIndexOutOfBoundsException e){ System.out.println("Out of boundary"); } catch(ArithmeticException e){ System.out.println("Divide by zero"); } catch(Exception e){ System.out.println("Some Other Exception"); }

All methods in an abstract class must be declared as abstract methods.

Which term describes an entity that has different meanings?

A subclass cannot inherit which members of its superclass?

To make an attribute read-only, which approach should be implemented?

What is the output of this code? package radio; public class Song { public void playMusic() { System.out.print("Play!"); } } private static int playMusic() { System.out.print(" Music!"); } public static void main(String[] tracks) { new Song().playMusic(); }

With which modifier is code accessible in the same package and in subclasses?

Given the following code: class Employee { private void myname() { System.out.println("I am an Employee"); } public static void main(String[] args) { Employee.myname(); } } What is the output of this code?

Given the following code: public class Vehicle { public void move() { System.out.println("The vehicle moves"); } } public class Car extends Vehicle { public void move() { System.out.println("The car moves"); } } public class Main { public static void main(String[] args) { Vehicle vehicle = new Car(); vehicle.move(); } } The output of this code is...

Is it possible to override a static method?

Is it possible to overload a static method?

The new keyword creates objects at compile time.

Given the following class description, select the correct statement for implementing getter and setter for the age attribute such that age must be within the range of 20 to 40 inclusive. public class Student { private String name; private int age; } Which implementation requirement is correct?

Given the following code, what change is needed to properly override the watch() method? package entertainment; class Television { protected final void watch() {} } public class LCD extends Television { Object watch() {} }

Object-oriented programming allows you to derive new classes from existing classes. This is called .............

Which of the following statements is true?

What is the output of running class C? class A { public A() { System.out.println("A Constructor"); } } class B extends A { public B() { System.out.println("B Constructor"); } } public class C { public static void main(String[] args) { B b = new B(); } }

Which of the following is incorrect?

Which of the statements regarding the super keyword is incorrect?

Which of the following statements is not true?

Which of the following implements polymorphism?

public class Test { public static void main(String[] args) { String s = new String("Welcome to EELU"); Object o = s; String d = (String) o; } } Which statement is correct?

What is the output of the following code? public class Test { public static void main(String[] args) { String s1 = new String("Java"); String s2 = new String("Java"); System.out.print((s1 == s2) + " " + (s1.equals(s2))); } }

Given two reference variables t1 and t2, if t1==t2 is true. Then .............

What will happen when we compile and run the following code? class Computer { protected int process() { return 5; } } class Laptop extends Computer { public int process() { return 3; } } public static void main(String[] chips) { System.out.print(new Laptop().process()); }

For the following Java class, what is printed when the program runs? public class Test { private static int instanceCtr = 0; public Test() { instanceCtr++; } public static int getInstanceCount() { return instanceCtr; } public static void main(String[] args) { Test obj1 = new Test(); Test obj2 = new Test(); Test obj3 = new Test(); System.out.println("Number of instances created: " + Test.getInstanceCount()); } }

What is the output of the following application? public class Baseball { public static void main(String... teams) { try { int score = 1; System.out.print(score++); } catch (Throwable t) { System.out.print(score++); } finally { System.out.print(score++); } System.out.print(score++); } }

Which of the following is a checked exception?

Which of the following statements about a finally block is true?

Which statement about the role of exceptions in Java is incorrect?

If an exception matches two or more catch blocks, which catch block is executed?

Which modifier can be applied to an abstract interface method?

Which of the following statements about interfaces is not true?

Excluding default and static methods, .......... can contain both abstract and concrete methods, while .......... contains only abstract methods.

What will the output of the provided abstract class and subclass implementation be? abstract class Car { static {System.out.print("1")} public Car(String name) { super(); System.out.print("2"); } { System.out.print("3"); } } public class BlueCar extends Car { { System.out.print("4"); } public BlueCar() { super("blue"); System.out.print("5"); } public static void main(String[] gears) { new BlueCar(); } }

A Java exception is an instance of ..........

The code that sets the size of the button btn to 30 pixels height and 60 width and position at pixels 30 from the left and pixels 60 from the top of the container is ........

What is the output of the following application involving static blocks and initialization? class A { static int i = 10; static { System.out.println(1); i = 100; } } public class StatInitializationBlock{ static { System.out.println(2); } public static void main(String [] args){ System.out.println(3); System.out.println(A.i); } }

Which of the following are primitives? int[] lowercase = new int[0]; Integer[] uppercase = new Integer[0];

Which of the following is the proper code to determine the number of elements in an array?

Which of the following create an empty two-dimensional array with dimensions 2x2?

The Scanner class method used for reading a line of text is ........

Which of the following is the right syntax of defining a file handle in Java?

Java AWT components are platform-dependent.

Java Swing components have different look and feel for the different platforms.

The Container is a component in AWT that can contain other containers.

The java.awt.event package provides many event listener classes for event handling.

The event object only carries the information about the event occurred.

We create event listener class by extending ActionListener class.

FlowLayout is the default layout manager for every java JFrame.

FlowLayout is the default layout manager for every JPanel.

LinkedList is a data structure that does not need shift in insertion operation.

Queue is the class that implements last-in-first-out data structure.

Stack is the class that implements first-in-first-out data structure.

ArrayList allows random access of possibly duplicated elements.

The elements in TreeSet are stored in ascending order.

Polymorphism means writing code that will work for types not known at the time of writing the code.

Overloading is a mechanism that is considered as a type of inclusion polymorphism.

Abstraction is a process of hiding the functionality details and showing only implementation to the user.

To extend an abstract class we must override all its methods.

To implement method overloading, the method declared in child class must be more restrictive.

The java final keyword is used to restrict the use of variables, methods, and classes.

In Java, input streams are only used to read data from a data source.

All collection classes implement the Iterable interface.

The method put() is the one that puts a new item on top of a stack.

Set is an ordered collection that doesn’t allow storing duplicate items.

The elements in TreeSet collection are stored in ascending order.

Which of the following statements about a finally block is true?

Exception Handling in Java handles ............

Which of the following exception types is a checked exception?

If an exception matches two or more catch blocks, which catch block is executed?

Which of the following statements about interfaces is not true?

A Java exception is an instance of

If the types for which a piece of code works are finite, then it is considered as an implementation of ............

Type of polymorphism that is achieved by using a type variable when writing the code rather than using any specific type is called ............

Which of the following is true?

The process of determining the appropriate method or function to call at runtime, based on the actual type of the object rather than the reference type is called ...............

Multiple inheritance can be achieved using .................

Which of the following is false?

Which of the following code blocks that contains a code where an exception may occur

An object that is notified by the event source when an event occurs is called ............

Which of the following is true about a final method?

interfaces can implement other interfaces. Choose True or False.

An abstract interface method can have a static modifier. Choose True or False.

Polymorphism supports maintainability. Choose True or False.

Abstract classes can have only abstract methods. Choose True or False.

Any class which extends abstract class must override all its abstract methods. Choose True or False.

Both an interface and its constructor must have the same name. Choose True or False.

All fields in an interface are implicitly public, static, and final. Choose True or False.

Interface methods are by default abstract and private. Choose True or False.

Overloading is a Universal polymorphism. Choose True or False.

final is not allowed for Constructors. Choose True or False.

What is the output of the following application? package machines; class Computer { protected final int process() { return 5; } } public class Laptop extends Computer { public final int process() { return 3; } public static void main(String[] chips) { System.out.printf(new Laptop().process()); } } Select the correct output.

What is the output of the following application? class A { static int i; static { System.out.println(1); i = 100; } } public class StaticInitializationBlock { static { System.out.println(2); } public static void main(String[] args) { System.out.println(3); System.out.println(A.i); } } Select the sequence of lines printed, one per line.

What is the output of the following application? public class A { { System.out.println("First"); } { System.out.println("Second"); } { System.out.println("Third"); } public A() { System.out.println("Fourth"); } public static void main(String[] args) { System.out.println("Fifth"); A a = new A(); } } Select the correct order of lines printed.