why wait(), notify() and notifyAll() methods in Java must be called from a synchronized method or block is asked quite frequently in Java interviews. This post gives some of the points why it makes sense to call wait(), notify() and notifyAll() methods with in a synchronized context. You need to…
Condition interface which resides in java.util.concurrent.locks has methods for inter thread communication similar to Object class monitor methods (wait, notify and notifyAll). Condition provides methods like await(), signal(), signalAll(). Where a Lock replaces the use of synchronized methods and statements, a Condition replaces the use of the Object monitor methods.…
HashSet in Java is part of the Java Collections framework and one of the most used Set implementation in Java applications. HashSet class extends AbstractSet class and implements Set, Cloneable and Serializable interfaces. HashSet is backed by a HashMap instance that means HashSet class internally uses HashMap to store its…
In Java exception handling there are lots of exception classes that can be used for handling exceptions. Though some times you may not find an appropriate exception class that clearly represents the exception thrown from your code, in such scenario you may choose to create your own custom exception class.…
When an exception is thrown in a code the normal execution flow of the method is disrupted and that may result in opened resources never getting closed. In such scenarios you do need a clean up mechanism that’s where finally block in Java helps. For Example, suppose in a method…
