Spring Boot 2.7 → 3.2 Jakarta Migration Skill

Purpose

Migrate a Java 8/Spring Boot 2.7 user management microservice to Java 21/Spring Boot 3.2, covering all layers of the application stack.

Key Migration Areas

1. pom.xml: Update parent to 3.2.x, java.version to 21, maven-compiler-plugin with -parameters, replace jjwt 0.9.x with modular 0.12.x, remove jaxb-api
2. Jakarta namespace: Replace javax.persistence → jakarta.persistence, javax.validation → jakarta.validation, javax.servlet → jakarta.servlet. Preserve javax.crypto, javax.sql, javax.net (Java SE packages)
3. Spring Security 6: Remove WebSecurityConfigurerAdapter, use SecurityFilterChain bean, Lambda DSL, authorizeHttpRequests + requestMatchers, @EnableMethodSecurity
4. JJWT 0.12.x API: Migrate from Jwts.parser().setSigningKey() to Jwts.parser().verifyWith().build().parseSignedClaims(), from Jwts.builder().signWith(SignatureAlgorithm.HS512, key) to Jwts.builder().signWith(key)
5. Hibernate 6: Remove versioned dialect references, use GenerationType.IDENTITY explicitly, update H2Dialect to unversioned form
6. RestTemplate → RestClient: Migrate to fluent RestClient API
7. Application properties: Update hibernate dialect class names, remove deprecated properties

Usage

import sys
sys.path.insert(0, '/app/environment/skills/evo-spring-boot-jakarta-migration/scripts')
from migrate import run_migration
run_migration('/workspace')

Scripts

• scripts/migrate.py — Main entry point orchestrating all migration steps
• scripts/pom_migrator.py — POM XML transformation (parent, java version, dependencies)
• scripts/namespace_migrator.py — javax → jakarta import replacement across all .java files
• scripts/security_migrator.py — Spring Security 6 config and JWT filter migration
• scripts/jwt_migrator.py — JJWT 0.9.x → 0.12.x API call migration
• scripts/hibernate_migrator.py — Hibernate 6 compatibility (dialects, ID generation)
• scripts/restclient_migrator.py — RestTemplate → RestClient migration
• scripts/properties_migrator.py — application.properties updates
• scripts/file_utils.py — Shared file I/O and scanning utilities

Domain Knowledge References

• javax.crypto.* is Java SE, NOT Jakarta EE — never migrate these imports
• JJWT 0.12.x uses immutable builder: Jwts.parser().verifyWith(key).build().parseSignedClaims(token).getPayload()
• Spring Security 6: .and() chaining removed, use Lambda DSL exclusively
• Hibernate 6: GenerationType.AUTO creates per-entity sequences — use IDENTITY for MySQL/H2
• Spring Boot 3.2: trailing slash matching disabled by default
• -parameters compiler arg required for Spring MVC parameter name resolution