paw-persistence-contracts-layer

Design batch operation patterns directly into DAO contracts so related entities are fetched in a single query rather than looping through individual requests, eliminating database query loops in service layers.

Abstract JDBC implementation details from DAO interfaces by enforcing strict contract abstraction guards that keep implementation details like row mappers out of the interface. This maintains TP1 JDBC compatibility while ensuring the service layer remains decoupled from the underlying persistence technology.

Design JPA-backed persistence contracts for batch operations by defining TP2 contracts that enforce behavior-oriented naming and batch patterns. This involves creating DAO interfaces that support batch reservation updates while abstracting JPA implementation specifics away from the service layer.

Implementation leakage happens in persistence layer design when DAO interfaces expose JDBC or JPA-specific details like row mappers or entity annotations. This breaks abstraction discipline between service layers and persistence implementations, creating tight coupling and making the system harder to maintain.

Yes, this persistence abstraction approach supports both TP1 JDBC contracts and TP2 JPA-backed contracts. It enforces naming conventions and batch operation patterns across both implementations while keeping behavior-oriented method signatures free of technology-specific details.

Audit existing DAO contracts for implementation leakage and N+1 vulnerabilities by checking for JDBC or JPA types in interface signatures and identifying methods that trigger queries inside loops. This skill applies compile-time verification to catch these issues during contract design.