Tip: Analyse impact on put and get method Case 1: - hashcode override - No   equals override - No What Will Happen- when you try to …

Singleton When there is only one instance creation is allowed OR We want to restrict instance creation of particular class and allow only one instanc…

Join is method from thread class. It can be called on thread object and when it is called, current thread will wait for other thread (on which join is ca…

CountDownLatch is utility under java.util.concurrent package. We initialise CountDownLatch with some integer count value. One or more threads will wa…

Sleep is method from Thread class. This can be called without object and will act on current running thread. Calling sleep on current thread will throw…

There are two ways you can create threads By extending Thread class from java.lang package By Implementing Runnable interface Lets explore these m…

Hi Readers, If you are beginner with Java then let me introduce your to constructor. Constructor class Animal() { public Animal ( ) { Sy…