10 sample FAQs - coreJava

1 what is a transient variable
A transient variable is a variable that may not be serialized.

2 which containers use a border Layout as their default layout
The window, Frame and Dialog classes use a border layout as their default layout.

3 Why do threads block on I/O
Threads block on i/o (that is enters the waiting state) so that other threads may execute while the i/o Operation is performed.

4 How are Observer and Observable used
Objects that subclass the Observable class maintain a list of observers. When an Observable object is updated it invokes the update() method of each of its observers to notify the observers that i...

5 What is synchronization and why is it important
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 ...

6 Can a lock be acquired on a class
Yes, a lock can be acquired on a class. This lock is acquired on the class's Class object..

7 What's new with the stop(), suspend() and resume() methods in JDK 1.2
The stop(), suspend() and resume() methods have been deprecated in JDK 1.2.

8 Is null a keyword
The null value is not a keyword.

9 What is the preferred size of a component
The preferred size of a component is the minimum component size that will allow the component to display normally.

10 What method is used to specify a container's layout
The setLayout() method is used to specify a container's layout.