IBM Technical Lead Interview Questions and Answers

Object oriented principles are a set of programming concepts that focus on objects and their interactions.

• Encapsulation - bundling data and methods that operate on that data within a single unit

• Inheritance - creating new classes from existing ones, inheriting their properties and methods

• Polymorphism - ability of objects to take on many forms, allowing for flexibility and extensibility

• Abstraction - hiding implementation...read more

Compile time polymorphism is achieved through function overloading and templates, while run time polymorphism is achieved through virtual functions and inheritance.

• Compile time polymorphism is resolved at compile time, while run time polymorphism is resolved at run time.

• Function overloading is an example of compile time polymorphism, where multiple functions with the same name but different parameters are defined.

• Templ...read more

Compile time polymorphism is method overloading while runtime polymorphism is method overriding.

• Compile time polymorphism is resolved at compile time while runtime polymorphism is resolved at runtime.

• Method overloading is an example of compile time polymorphism where multiple methods have the same name but different parameters.

• Method overriding is an example of runtime polymorphism where a subclass provides its own imp...read more

Compile-time polymorphism is method overloading while runtime polymorphism is method overriding.

• Compile-time polymorphism is resolved at compile-time while runtime polymorphism is resolved at runtime.

• Method overloading is an example of compile-time polymorphism where multiple methods have the same name but different parameters.

• Method overriding is an example of runtime polymorphism where a subclass provides its own imp...read more

Answering questions on Java 8 features such as streams, concurrent API, optional class, functional interface, lambda, and comparable vs comparator.

• Java 8 streams can be used to sort arrays based on specific criteria

• Concurrent API in Java 8 allows for parallel processing of data

• Optional class is used to handle null values in a more efficient way

• Functional interfaces are interfaces with only one abstract method, used for...read more

IOC Container is a core feature of Spring Framework that manages the dependencies between objects.

• IOC stands for Inversion of Control

• It is used to achieve loose coupling between objects

• It allows objects to be created and wired together by an external framework

• It reduces the amount of code needed for configuration and maintenance

• Examples of IOC Containers in Spring are ApplicationContext and BeanFactory

We use @Value in Spring Boot to inject values from properties files or environment variables.

• Allows for external configuration of application properties

• Values can be injected from properties files or environment variables

• Can be used to inject values into fields, constructors, or methods

• Example: @Value("${my.property}") private String myProperty;

SQL databases are relational and use structured data, while NoSQL databases are non-relational and use unstructured data.

• SQL databases use tables with predefined schema, while NoSQL databases use documents, key-value pairs, or graphs.

• SQL databases are better for complex queries and data analysis, while NoSQL databases are better for scalability and flexibility.

• Examples of SQL databases include MySQL, Oracle, and Postgr...read more

Abstract classes and interfaces are used to achieve abstraction and provide a blueprint for classes to implement.

• Used abstract class to create a base class for different types of vehicles, with common properties and methods.

• Used interface to define a contract for different payment methods, with each method implementing its own logic.

• Abstract classes are used when we want to provide a default implementation for some met...read more

Authentication and authorization were handled using a combination of technologies and protocols.

• Used OAuth 2.0 for authentication

• Implemented role-based access control for authorization

• Stored user credentials securely using bcrypt hashing algorithm

• Used JSON Web Tokens (JWT) for session management

• Implemented two-factor authentication for sensitive operations

Customer information will be encrypted using industry-standard encryption algorithms and stored securely.

• Use industry-standard encryption algorithms such as AES or RSA

• Ensure that encryption keys are securely stored and managed

• Implement secure storage mechanisms such as hashing and salting

• Regularly review and update encryption protocols to ensure they remain secure

Serialization is used to convert complex data structures into a format that can be easily transmitted or stored.

• Serialization allows data to be sent over a network or saved to a file.

• It enables objects to be stored in a database or memory.

• Serialization is used in web services, messaging systems, and distributed computing.

• Examples include JSON, XML, and binary formats like Protocol Buffers and Apache Avro.

Yes, I have experience with Jenkins and Cloud Deployment.

• I have used Jenkins for continuous integration and continuous deployment.

• I have experience with setting up Jenkins pipelines for automated deployment.

• I have worked with cloud platforms like AWS and Azure for deploying applications.

• I have used tools like Ansible and Terraform for infrastructure automation.

• I have experience with containerization using Docker and Ku...read more

Yes, logging is an essential part of software development.

• Logging helps in debugging and troubleshooting issues.

• It provides a record of events and actions taken by the system.

• It helps in monitoring system performance and identifying bottlenecks.

• Examples of logging mechanisms include log4j, syslog, and ELK stack.