Hindustan Petroleum Trainee Interview Questions and Answers

Answers to questions related to Docker, AWS firewall types, and ELK Stack

• To create a Docker file, start with a base image and add necessary dependencies and configurations

• AWS has two types of firewalls: Network ACLs and Security Groups

• ELK Stack is a combination of Elasticsearch, Logstash, and Kibana used for log management and analysis

Faced challenges in a project and how tackled them

• One of the challenges was managing conflicting priorities among stakeholders. I tackled it by setting clear expectations and priorities, and communicating regularly with all parties involved.

• Another challenge was dealing with unexpected technical issues. I tackled it by conducting thorough research, consulting with experts, and testing different solutions until the issu...read more

Encapsulation is the process of hiding implementation details and exposing only necessary information to the user.

• Encapsulation is a fundamental concept in object-oriented programming.

• It helps in achieving data abstraction and information hiding.

• It allows for better control over the data and prevents unauthorized access.

• Encapsulation is implemented using access modifiers such as public, private, and protected.

• For examp...read more

Dialect in Hibernate is a configuration setting that defines the type of database used.

• Dialect is responsible for generating SQL statements specific to the database.

• It handles the differences in SQL syntax and data types between different databases.

• Examples of dialects include MySQLDialect, OracleDialect, and PostgreSQLDialect.

Interface defines the contract between two entities while Abstraction hides the implementation details.

• Interface is a blueprint of a class that defines the methods and properties that a class must implement.

• Abstraction is a way of hiding the implementation details of a class and exposing only the necessary details to the user.

• Interface is used for achieving multiple inheritance in Java.

• Abstraction is used for achieving...read more

OOPs concepts in Java are the fundamental principles of object-oriented programming.

• Encapsulation: wrapping data and code into a single unit

• Inheritance: creating new classes from existing ones

• Polymorphism: using a single interface to represent multiple types

• Abstraction: hiding implementation details from the user

• Examples: class, object, inheritance, polymorphism, encapsulation

Stack is a LIFO data structure while Queue is a FIFO data structure.

• Stack follows Last In First Out (LIFO) principle while Queue follows First In First Out (FIFO) principle.

• Stack has two main operations: push and pop while Queue has two main operations: enqueue and dequeue.

• Stack is used in recursive function calls, undo/redo operations, and backtracking while Queue is used in breadth-first search, printing tasks in ord...read more

SQL query to find second highest salary in database

• Use ORDER BY and LIMIT to get the second highest salary

• Assume ties are allowed and use DISTINCT

Method overloading is having multiple methods with the same name but different parameters. Method overriding is having a method in a subclass with the same name and parameters as a method in its superclass.

• Method overloading is done within the same class while method overriding is done in different classes (subclass and superclass).

• Method overloading is achieved by changing the number of parameters or the data type of ...read more

The parent class of all classes in Java is the Object class.

• All classes in Java implicitly extend the Object class.

• The Object class provides basic methods such as toString(), equals(), and hashCode().

• Any class can override these methods to provide custom implementations.

• Example: public class MyClass extends Object { ... }

• Example: Object obj = new MyClass();

SQL databases are relational and use structured query language, while NoSQL databases are non-relational and use various data models.

• SQL databases are based on a fixed schema, while NoSQL databases are schema-less.

• SQL databases use tables to store data, while NoSQL databases use various data models like key-value, document, columnar, or graph.

• SQL databases are better suited for complex queries and structured data, whil...read more

TCS stands for Tata Consultancy Services, a multinational IT services company based in India.

• TCS is one of the largest IT services companies in the world.

• It provides a wide range of services including consulting, software development, and business process outsourcing.

• TCS has clients in various industries such as banking, healthcare, and retail.

• The company has a strong focus on innovation and has several research and de...read more