TestEngineer

why collectoion is introduced into the market? how to sort elements in alphabetical order? what is the difference between collection and collectons? different concepts of collections? what is the difference between set and list? what is the difference between list set and map? what is the difference between hashset and linlkedlist? what are the types of iterators presrent in the collections? difference between linkedlist and hashmap? what is queue? waht is the difference between treeset and linked hashset? what is difference betwen treemap and hashmap? what is the differnce between vector and arraylist? difference between iterator and listiterator? what is sortedset and tailset and headset?

difference between class and object? what  are class variables and local variables? what is the difference between static and final ? what are the modifiers present in java? what are access modifiers and non access modifieres? what about static block? why we use static block? what about try catch block? can we write try without catch? what is finally block in java? how many catch blocks we can write for one try block? what is tyhe difference between final and finally and finallyze? what is the use of constructor in java? what is the use super key word in java? what is the use of the this keyword in java? what is the use of this keyword in constructors calling? what is wrapper classes? Difference between throw and throws and throwable? difference between string and string buffer and string builder? can we overload a constructor? what is inheritance? different types of inheritance? what is polymorphism? different types of polymorphism? what is abstraction? w...