struts-jsp-testing

Characterization tests for legacy Struts actions capture current endpoint behavior and database state before migration. You generate structured testing patterns using JUnit and mock requests, creating safety nets that ensure behavior is preserved while modernizing the codebase.

Yes, you can unit-test both Struts 1.x and Struts 2.x actions using mock requests or direct POJOs. This approach isolates controller logic and verifies action mappings without deploying the full legacy application to a servlet container.

Dual-run testing executes identical tests against legacy and new endpoints to guarantee functional parity during migration. This contract testing method ensures the modernized framework produces the same outputs and state changes as the original Struts/JSP application.

Using an in-memory database like H2 for legacy DAO layer tests provides isolated data-access verification. It executes repository tests quickly without relying on external database state, ensuring migration safety nets remain deterministic and repeatable.

Integrating migration safety tests into a CI pipeline requires running characterization and dual-run tests on every commit. This strategy continuously validates that new framework changes preserve the original Struts/JSP endpoint contracts and database behavior throughout modernization.