Cognizant Java Developer Interview Questions, Process, and Tips

Java Developer interview questions covering array list, linkedlist, hashmap, synchronization, abstract vs interface, singleton class, Spring framework, database configuration, and Java 8 features.

• ArrayList and LinkedList differ in terms of implementation, performance, and usage

• HashMap uses hashing to store and retrieve key-value pairs

• Synchronized is used to ensure thread safety and prevent race conditions

• Abstract class...read more

HashMap is a data structure that stores key-value pairs and uses hashing to retrieve values quickly.

• HashMap uses hashing to store and retrieve values based on their keys.

• It uses an array of buckets to store the key-value pairs.

• The hash code of the key is used to determine the index of the bucket where the pair will be stored.

• If two keys have the same hash code, they are stored in the same bucket as a linked list.

• HashMa...read more

This interview question covers various topics including programming, design patterns, data structures, and exception handling in Java.

• Write a program to generate the Fibonacci series

• Write a program using boolean variables

• Explain the ClassCastException and how to handle it

• Discuss the Singleton design pattern and its implementation with different JDK versions

• Explain abstract classes and interfaces in your current project

• ...read more