Java Interview Questions - Page 5
Question: How to create multithread in a program?
Answer: You have two ways to do so.
First, making your class "extends" Thread class. Second,
making your class "implements" Runnable interface. Put jobs
in a run() method and call start() method to start the thread.
Question: Can Java object be locked down for exclusive use by a given thread?
Answer:
Yes. You can lock an object by putting it in a "synchronized"
block. The locked object is inaccessible to any thread other than the one
that explicitly claimed it
Question: Can each Java object keep track of all the threads that want to
exclusively access to it?
Answer: Yes
Question: What state does a thread enter when it terminates its processing?
Answer:
When a thread terminates its processing, it enters the dead state.
Question: What invokes a thread's run() method?
Answer: After a thread is started, via
its start() method of the Thread class, the JVM invokes the thread's run()
method when the thread is initially executed.
Question: What is the purpose of the wait(), notify(), and
notifyAll() methods?
Answer:
The wait(),notify(), and notifyAll() methods are used to provide an
efficient way for threads to communicate each other.
Question: What are the high-level
thread states?
Answer: The high-level thread states
are ready, running, waiting, and dead.
Question: What is the Collections API?
Answer: The Collections API is a set of classes
and interfaces that support operations on collections of objects.
Question: What is the List interface?
Answer: The List interface provides support for
ordered collections of objects.
Question: How does Java handle integer overflows and underflows?
Answer: It uses those
low order bytes of the result that can fit into the size of the type allowed
by the operation.