Home Interviewquestions Corejava Core Java Interview Question, Interview Question
Questions:Ask|Latest


 
 

Share on Google+Share on Google+

Core Java Interview Question, Interview Question

Advertisement
This page discusses - Core Java Interview Question, Interview Question

Core Java Interview Question Page 15

     

Question: What invokes a thread's run() method?

Answer: After a thread is started, via its start() method or that of the Thread class, the JVM invokes the thread's run() method when the thread is initially executed.

Question: What is the difference between the Boolean & operator and the && operator?

Answer: If an expression involving the Boolean & operator is evaluated, both operands are evaluated. Then the & operator is applied to the operand. When an expression involving the && operator is evaluated, the first operand is evaluated. If the first operand returns a value of true then the second operand is evaluated. The && operator is then applied to the first and second operands. If the first operand evaluates to false, the evaluation of the second operand is skipped.

Question: Name three subclasses of the Component class.

Answer: Box.Filler, Button, Canvas, Checkbox, Choice, Container, Label, List, Scrollbar, or TextComponent

Question: What is the GregorianCalendar class?

Answer: The GregorianCalendar provides support for traditional Western calendars.

Question: Which Container method is used to cause a container to be laid out and redisplayed?

Answer: validate()

Question: What is the purpose of the Runtime class?

Answer: The purpose of the Runtime class is to provide access to the Java runtime system.

Question: How many times may an object's finalize() method be invoked by the garbage collector?

Answer: An object's finalize() method may only be invoked once by the garbage collector.

Question: What is the purpose of the finally clause of a try-catch-finally statement?

Answer: The finally clause is used to provide the capability to execute code no matter whether or not an exception is thrown or caught.

Question: What is the argument type of a program's main() method?

Answer: A program's main() method takes an argument of the String[] type.

Question: Which Java operator is right associative?

Answer: The = operator is right associative.

Question: What is the Locale class?

Answer: The Locale class is used to tailor program output to the conventions of a particular geographic, political, or cultural region.

Question: Can a double value be cast to a byte?

Answer: Yes, a double value can be cast to a byte.

Question: What is the difference between a break statement and a continue statement?

Answer: A break statement results in the termination of the statement to which it applies (switch, for, do, or while). A continue statement is used to end the current loop iteration and return control to the loop statement.

Question: What must a class do to implement an interface?

Answer: It must provide all of the methods in the interface and identify the interface in its implements clause.

Question: What method is invoked to cause an object to begin executing as a separate thread?

Answer: The start() method of the Thread class is invoked to cause an object to begin executing as a separate thread.

Question: Name two subclasses of the TextComponent class.

Answer: TextField and TextArea

Question: What is the advantage of the event-delegation model over the earlier event-inheritance model?

Answer: The event-delegation model has two advantages over the event-inheritance model. First, it enables event handling to be handled by objects other than the ones that generate the events (or their containers). This allows a clean separation

between a component's design and its use. The other advantage of the event-delegation model is that it performs much better in applications where many events are generated. This performance improvement is due to the fact that the event-delegation model does not have to repeatedly process unhandled events, as is the case of the event-inheritance model.

Advertisements

Liked it!  Share this Tutorial


Follow us on Twitter, or add us on Facebook or Google Plus to keep you updated with the recent trends of Java and other open source platforms.

Posted on: April 18, 2011

Ask Questions?    Discuss: Core Java Interview Question, Interview Question  

Post your Comment


Your Name (*) :
Your Email :
Subject (*):
Your Comment (*):
  Reload Image
 
 
Comments
DMCA.com