Java Advanced Java - Technical Questions and Answers

1.	What is a transient variable?
	Answer: A transient variable is a variable that may not be serialized. Workspace Report errors ... Name : Email: View Answer

2.	Which containers use a border Layout as their default layout?
	Answer: The Window, Frame and Dialog classes use a border layout as their default layout. Workspace Report errors ... Name : Email: View Answer

3.	Why do threads block on I/O?
	Answer: Threads block on I/O (that is enters the waiting state) so that other threads may execute while the I/O Operation is performed. Workspace Report errors ... Name : Email: View Answer

4.	How are Observer and Observable used?
	Answer: 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 it has changed state. The Observer interface is implemented by objects that observe Observable objects. Workspace Report errors ... Name : Email: View Answer

5.	What is synchronization and why is it important?
	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. Workspace Report errors ... Name : Email: View Answer

6.	Can a lock be acquired on a class?
	Answer: Yes, a lock can be acquired on a class. This lock is acquired on the class's Class object.. Workspace Report errors ... Name : Email: View Answer

7.	What's new with the stop(), suspend() and resume() methods in JDK 1.2?
	Answer: The stop(), suspend() and resume() methods have been deprecated in JDK 1.2. Workspace Report errors ... Name : Email: View Answer

8.	Is null a keyword?
	Answer: The null is not a keyword. Workspace Report errors ... Name : Email: View Answer

9.	What is the preferred size of a component?
	Answer: The preferred size of a component is the minimum component size that will allow the component to display normally. Workspace Report errors ... Name : Email: View Answer

10.	What method is used to specify a container's layout?
	Answer: The setLayout() method is used to specify a container's layout. Workspace Report errors ... Name : Email: View Answer

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