TCS Java Developer Interview Questions, Process, and Tips

HashMap is non-synchronized and allows null values, while hash table is synchronized and does not allow null values.

• HashMap is non-synchronized and not thread-safe, while hash table is synchronized and thread-safe.

• HashMap allows null values and one null key, while hash table does not allow null keys or values.

• HashMap is generally preferred for non-thread-safe applications, while hash table is used in thread-safe applic

OOP is a programming paradigm based on the concept of objects, which can contain data in the form of fields and code in the form of procedures.

• OOP focuses on creating objects that interact with each other to solve problems.

• Encapsulation: Objects can hide their internal state and require interaction through defined interfaces.

• Inheritance: Objects can inherit attributes and methods from other objects.

• Polymorphism: Object...read more

An interface in programming is a blueprint of a class that defines a set of methods that a class must implement.

• Interfaces in Java are used to achieve abstraction and multiple inheritance.

• Interfaces contain only method signatures, not method bodies.

• Classes can implement multiple interfaces but can only extend one class.

• Example: interface Shape { void draw(); }

• Example: class Circle implements Shape { public void draw()

HashMap works internally using an array of buckets to store key-value pairs, with each bucket containing a linked list of entries.

• HashMap uses hashing to determine the index of the bucket where the key-value pair should be stored.

• If multiple key-value pairs hash to the same index, they are stored in a linked list within that bucket.

• When retrieving a value, the key's hash code is used to find the correct bucket, then th...read more

application.properties is used to store configuration settings for Java applications.

• Centralized storage for configuration settings

• Easy to update without changing code

• Allows for different configurations for different environments (development, testing, production)

• Can be used to store database connection details, API keys, logging settings, etc.