bohdaq - Java Developer

Enterprise Java Excellence

As a Java developer, I specialize in building robust, scalable enterprise applications using Spring Boot and the Spring Framework ecosystem. My expertise spans from developing RESTful APIs to implementing real-time communication with WebSocket, always focusing on clean architecture, maintainability, and performance.

I have extensive experience with the entire Java ecosystem, including Maven and Gradle for build automation, JUnit and Mockito for testing, and modern Java features for writing efficient, type-safe code. Whether it's building microservices, implementing security features, or optimizing application performance, I deliver production-ready solutions.

Java Expertise

Core Java & Frameworks

Java 8+ (Streams, Lambdas, Optional)
Spring Boot & Spring Framework
Spring MVC & Spring WebFlux
Spring Data JPA & Hibernate
Spring Security
Spring Cloud (Microservices)

APIs & Communication

RESTful API Design & Development
WebSocket & STOMP Protocol
GraphQL (Basic)
API Documentation (Swagger/OpenAPI)
Message Queues (RabbitMQ, Kafka)
gRPC & Protocol Buffers

Database & Persistence

JPA & Hibernate ORM
Spring Data JPA
SQL & Database Design
PostgreSQL, MySQL, H2
Database Migrations (Flyway, Liquibase)
Transaction Management

Testing & Quality

JUnit 5 & TestNG
Mockito & MockMvc
Integration Testing
Test Containers
Code Coverage (JaCoCo)
Static Analysis (SonarQube)

Build & DevOps

Maven & Gradle
Docker & Containerization
CI/CD Pipelines
Kubernetes Deployment
Application Monitoring
Logging (SLF4J, Logback)

Architecture & Design

Microservices Architecture
Clean Architecture & SOLID Principles
Design Patterns
Domain-Driven Design (DDD)
Event-Driven Architecture
API Gateway Patterns

Java Projects

Spring Boot WebSocket Application

Spring Boot WebSocket STOMP Angular

Real-time chat application demonstrating WebSocket integration with Spring Boot backend:

WebSocket server with STOMP protocol implementation
Real-time bidirectional communication
Message broker configuration (SockJS fallback)
Spring Security integration for authentication
RESTful API endpoints for user management
Angular frontend for seamless user experience
Comprehensive unit and integration tests

View on GitHub →

Enterprise REST API

Spring Boot REST API JPA PostgreSQL

Production-ready RESTful API built with Spring Boot best practices:

Clean architecture with layered design
Spring Data JPA for database operations
Custom exception handling and validation
API versioning and documentation (Swagger)
JWT-based authentication and authorization
Comprehensive error responses
Performance optimization and caching

Microservices Architecture

Spring Cloud Microservices Docker Kubernetes

Scalable microservices architecture using Spring Cloud:

Service discovery with Eureka
API Gateway with Spring Cloud Gateway
Distributed configuration management
Circuit breaker pattern (Resilience4j)
Distributed tracing and monitoring
Containerized deployment with Docker
Kubernetes orchestration

Spring Security Implementation

Spring Security JWT OAuth2 Authentication

Comprehensive security implementation for enterprise applications:

JWT token-based authentication
OAuth2 and OpenID Connect integration
Role-based access control (RBAC)
Method-level security annotations
CSRF protection and CORS configuration
Password encryption and validation
Security audit logging

Event-Driven System

Spring Boot Kafka Event Sourcing CQRS

Event-driven architecture with Apache Kafka:

Kafka producer and consumer implementation
Event sourcing pattern
CQRS (Command Query Responsibility Segregation)
Message serialization and deserialization
Error handling and retry mechanisms
Event schema management
Monitoring and metrics

Batch Processing System

Spring Batch Scheduling Data Processing

Large-scale data processing with Spring Batch:

Chunk-oriented processing
Job scheduling and orchestration
Parallel and partitioned processing
Error handling and restart capabilities
Job monitoring and reporting
Integration with various data sources

Java Development Philosophy

🏗️ Clean Architecture

Following SOLID principles and clean code practices to create maintainable, testable, and extensible Java applications.

🧪 Test-Driven Development

Writing comprehensive unit, integration, and end-to-end tests to ensure code quality and catch regressions early.

🔒 Security First

Implementing security at every layer, from authentication to authorization, following OWASP guidelines and Spring Security best practices.

📈 Performance Optimization

Optimizing application performance through caching, connection pooling, query optimization, and profiling.

🔄 Continuous Integration

Leveraging CI/CD pipelines with automated testing, code quality checks, and deployment automation.

📚 Documentation

Maintaining comprehensive documentation including API specs, architecture diagrams, and code comments.

Java Ecosystem & Tools

Spring Ecosystem

Leveraging the full power of Spring Boot, Spring Cloud, Spring Security, and Spring Data for enterprise applications.

Build Tools

Expert use of Maven and Gradle for dependency management, build automation, and multi-module projects.

Testing Frameworks

Comprehensive testing with JUnit 5, Mockito, MockMvc, and TestContainers for reliable, maintainable code.

Modern Java

Utilizing modern Java features including streams, lambdas, records, pattern matching, and virtual threads.