ENH iSecure interview questions

OOPs Concepts Explain the four pillars of OOP (Encapsulation, Abstraction, Inheritance, Polymorphism). Difference between method overloading and method overriding. What is the use of the super and this keywords? Core & Advanced Java Explain exception handling and types of exceptions in Java. What are collections in Java? Explain ArrayList vs LinkedList. How does multithreading work in Java? Difference between Runnable and Thread. Java 8 Features What are lambda expressions and functional interfaces? Explain the use of Streams API with examples. How does the Optional class help in handling null values? Resume-Based Technical Questions Discussion on projects, technologies used, and problem-solving approaches. Questions on SQL queries and database handling in your projects. Coding Question Write a program to find the frequency of each character in a given string.

basics of java oops sql mongodb program on files and data manipulation in files using java