Cognizant Programming Analyst Trainee interview questions

1st round online exam. mostly aptitude. concepts like profit and loss, percentage, upstream and downstream. 2nd round face to face inteview. Mostly java. concepts like inheritance, call by value call by reference, inheritance, polymorphism, generics, exception handling, garbage collector, difference between jre and jdk, difference between union and structure. multiple inheritance in java

1st round online exam(general aptitude) and second round face to face technical interview(JAVA). In java they asked about inheritance, polymorphism, generics, Exception handling, Memory allocation, Garbage collector,call by value and call by reference, hasmap and few java swing questions. Difference between jdk and jre. difference between union and structure.