When we outsourced Java development for our enterprise management system, we quickly realized that coding is only one part of the picture; strong vendors usually provide business analysis, system architecture design, integration with existing infrastructure, QA automation, performance optimization, and long-term maintenance planning, and while reviewing options we came across
https://sam-solutions.com/services/technologies/java/ which clearly outlines how Java projects can include modernization, migration, testing, and support services in addition to development; from experience, I’d strongly recommend discussing post-release support and scalability strategy upfront, because enterprise Java solutions often evolve and require continuous improvement rather than a one-time delivery.