Java and Database Developer

e&e is seeking a Java and Database Developer for a hybrid contract opportunity in Harrisburg, PA! We are seeking a Java and Database Developer to support business-critical applications and services that exchange information between enterprise systems and external agencies. This role combines hands-on Java/Spring development, relational database development, enterprise integrations, and production support. The developer will maintain and enhance existing applications, troubleshoot application and data issues, support integrations, and implement controlled improvements while preserving established business functionality, data integrity, and system interfaces. The ideal candidate has strong SQL/database development skills along with experience supporting Java-based enterprise applications in a production environment. Key Responsibilities Develop, debug, maintain, and optimize complex SQL, stored procedures, triggers, views, scripts, and database business logic.Develop and maintain Java applications using Java 21, Spring Boot 3.x, Spring Batch, Spring Web, JDBC/JPA, and REST APIs.Support batch processing, scheduled jobs, file transfers, FTP/SFTP integrations, and message-based workflows.Maintain and troubleshoot enterprise integrations involving IBM MQ, REST APIs, messaging platforms, notifications, and connected application systems.Investigate and resolve production incidents, application errors, failed integrations, data discrepancies, and database-related issues.Participate in a weekly on-call rotation to support production systems and business-critical services.Maintain legacy Java and database applications by tracing existing business logic, diagnosing defects, and implementing targeted fixes and enhancements.Perform controlled refactoring while protecting existing business behavior, data integrity, and integration contracts.Improve application and database performance, reliability, logging, availability, maintainability, and recovery capabilities.Perform data reconciliation and data-quality analysis to identify and resolve inconsistencies across systems.Tune database queries and application components to improve performance and stability.Test, debug, review, and validate Java and database changes prior to production release.Collaborate with analysts, testers, DBAs, developers, and operations teams to deliver reliable, thoroughly tested solutions.Document technical changes, troubleshooting findings, integration behavior, and operational procedures. Requirements Approximately 3–5 years of professional experience developing and supporting Java applications and relational databases.Strong hands-on experience with relational database development, including complex stored procedures, triggers, views, joins, scripts, query tuning, and data reconciliation.Experience developing and maintaining applications using Java and Spring Boot.Experience with Spring Batch, Spring Web, REST APIs, JDBC/JPA, and service-layer development.Working knowledge of SAP ASE/Sybase or a comparable relational database platform.Experience with Microsoft SQL Server/T-SQL, Oracle PL/SQL, or another procedural SQL environment is transferable.Experience supporting enterprise integrations using REST APIs, IBM MQ, or comparable messaging technologies.Understanding of distributed application concepts including dependencies, retries, timeouts, failover, idempotency, and recovery.Experience supporting scheduled processing, message-based workflows, secure file transfers, and application logging.Strong production troubleshooting skills with the ability to diagnose application, integration, and database issues.Working knowledge of Maven, unit testing, mocking frameworks, debugging, and code review practices.Ability to work independently, take ownership of technical issues, and deliver complete and thoroughly tested solutions.Strong communication skills with the ability to clearly explain technical findings, issues, and resolutions.Ability to successfully complete a required criminal background check. Preferred Qualifications Experience with Java 17 or newer and Spring Boot 3.x.Experience with JDBC connection pooling, multiple data-source configurations, and production database troubleshooting.Familiarity with Docker and containerized applications.Exposure to Kubernetes or OpenShift.Experience with Git and CI/CD tools such as Jenkins, Azure DevOps, or GitHub Actions.Familiarity with monitoring and observability technologies such as Splunk, ELK, Prometheus, Grafana, OpenTelemetry, or distributed tracing.Understanding of application security technologies including OAuth2/OIDC, JWT, mutual TLS, certificates, and secrets management.Experience with integration testing and mocking tools such as Testcontainers, WireMock, contract testing, Selenium, or Cypress.Linux/Unix shell scripting or PowerShell experience.Exposure to load testing, performance testing, or capacity planning.Familiarity with React, Angular, Vue, TypeScript, HTML, or CSS for end-to-end application troubleshooting.Experience working in Agile/Scrum environments using pull requests, peer reviews, issue tracking, and technical documentation.