The Geeks Area

Java Tricky Questions 1. Is there any difference between a = a + b and a += b expressions? When we add two integral variables e.g. variables of type byte, short, or int in Java, then they are first promoted to int type, and then addition happens. The += operator implicitly casts the result of addition into the type of variable used to hold the result. What happens when you put return statement or System.exit () on try or catch block? Will finally block execute? It is a popular tricky Java interview question. Most of the programmers think that no matter what the finally block will always execute. This question challenges that concept by putting a return statement in the try or catch block or calling System.exit() from try or catch block. You can answer by saying that finally block executes even if we put a return statement in the try block or catch block. But finally block does not execute if you call System.exit() from try or catch block. 2. What does the expre...

Multi-threading 1.What are the minimum requirements for a Deadlock situation in a program?                       For a deadlock to occur following are the minimum requirements: Mutual exclusion : There has to be a resource that can be accessed by only one thread at any point of time. Resource holding : One thread locks one resource and holds it, and at the same time it tries to acquire lock on another mutually exclusive resource. No preemption : There is no pre-emption mechanism by which resource held by a thread can be freed after a specific period of time. Circular wait : There can be a scenario in which two or more threads lock one resource each and they wait for each other’s resource to get free. This causes circular wait among threads for same set of resources. 2. How can we prevent a Deadlock?                  ...