Sun Certified Java Developer Question:

Download Job Interview Questions and Answers PDF

Tell me What is native keyword and abstract keyword?

Answer:

Native keyword is prefixed with method name when we want that method to be implemented using a native language like c and c++. So in the class we only declare the method and the definition of the method is in the dll file.

Abstract key word is used to mark a method or a class as logically incomplete. The class which extends this class has to provide the definition of the method or has to declare the derived class as abstract.

We can not declare a native method inside a interface because by declaring a method in an interface we want all the implementers to give definitions to the methods defined. But by declaring a method native we mean that the implementation will come from some native language.

Download Sun Certification Interview Questions And Answers PDF

Previous Question

Next Question

Explain Which two statements are true? (Choose two.) A. It is possible for more than two threads to deadlock at once. B. The JVM implementation guarantees that multiple threads cannot enter into a deadlocked state. C. Deadlocked threads release once their sleep() methods sleep duration has expired. D. Deadlocking can occur only when the wait(), notify(), and notifyAll() methods are used incorrectly. E. It is possible for a single-threaded application to deadlock if synchronized blocks are used incorrectly. F. If a piece of code is capable of deadlocking, you cannot eliminate the possibility of deadlocking by inserting invocations of Thread.yield().

Explain Given: 1. public class Blip { 2. protected int blipvert(int x) { return 0; } 3. } 4. class Vert extends Blip { 5. // insert code here 6. } Which five methods, inserted independently at line 5, will compile? (Choose five.) A. public int blipvert(int x) { return 0; } B. private int blipvert(int x) { return 0; } C. private int blipvert(long x) { return 0; } D. protected long blipvert(int x) { return 0; } E. protected int blipvert(long x) { return 0; } F. protected long blipvert(long x) { return 0; } G. protected long blipvert(int x, int y) { return 0; }