What's Spurious wakeups ? What's Grid computing ? HashMap changes in Java 8 ? Likedhashmap vs Treemap ? Red black tree implementation Atomicity how it works ? Design pattern observer & it's intents ? Concurrency ? Threadpool executor rejection handler, if queue is full, if Max pool is full what will happen ? what is Class.forname ? Class loaders and principals ? Whar are inner Classes, how to create object of inner classes what is nested inner class ? Default values in XML spring , How will you use ternary operator ? How to minimise GC cycles ? Annotation ? 2nd largest in array ? Arraylist and linked list? Array remove middle values and print with null how to remove null in print ? Fibonacci ? Factorial ? Similarity between abstract class and interface ? What is sql injection ?