What are wrapped classes ?

Correct Answer: With respect to multithreading, synchronization is the capability to control the access of multiple threads to shared resources Without synchronization, it is possible for one thread to modify a shared object while another thread is in the process of using or updating that object's value This often leads to significant errors

Correct Answer: AWT are heavy-weight componenets Swings are light-weight components Hence swing works faster than AWT

Correct Answer: Pass By Reference means the passing the address itself rather than passing the value Passby Value means passing a copy of the value to be passed

Correct Answer: The purpose of garbage collection is to identify and discard objects that are no longer needed by a program so that their resources can be reclaimed and reused A Java object is subject to garbage collection when it becomes unreachable to the program in which it is used

Correct Answer: An abstract class can have instance methods that implement a default behavior An Interface can only declare constants and instance methods, but cannot implement default behavior and all methods are implicitly abstract An interface has all public members and no implementation An abstract class is a class which may have the usual flavors of class members (private, protected, etc), but has some abstract methods

Correct Answer: The wait(), notify(), and notifyAll() methods are used to provide an efficient way for threads to wait for a shared resource When a thread executes an object's wait() method, it enters the waiting state It only enters the ready state after another thread invokes the object's notify() or notifyAll() methods

Correct Answer: Top level class is also called outer class It is not defined inside any class Ex: class A { //top level class }

Correct Answer: Static member class is a class defined inside outer class with static modifier EX: Class A { //top level class or outer class static class B { //static member class } }

Correct Answer: Non-static member class is a class defined inside outer class with out static modifier EX: class A { // top level class or outer class class B { //non-static member class } }

Correct Answer: Local class is class defined inside method EX; class A { // top level class public static void main(string[] args) { class B { // local class } } }