java-legacy-analysis

name	java-legacy-analysis
description	Analyzes legacy Java applications (Java EE, Servlets, JSP, EJB, Spring) for migration readiness. Use when analyzing Java code structure, identifying framework-specific patterns, or understanding legacy Java architectures.

Purpose

Provide specialized knowledge for analyzing legacy Java applications to support migration planning and business logic extraction.

Application Type Detection

Type	Key Indicators
Servlet/JSP	web.xml, HttpServlet, doGet/doPost, *.jsp files
EJB	@Stateless, @Stateful, @MessageDriven, ejb-jar.xml
Spring (legacy)	applicationContext.xml, @Controller, @Service, @Repository
Spring Boot	@SpringBootApplication, application.properties, pom.xml with spring-boot-starter
Struts	struts-config.xml, Action classes, ActionForm
JSF	faces-config.xml, @ManagedBean, *.xhtml Facelets

Java Version Detection

• Check pom.xml for <maven.compiler.source> and <maven.compiler.target>
• Check build.gradle for sourceCompatibility and targetCompatibility
• Look for MANIFEST.MF entries
• Identify Java-version-specific APIs in use

Key Analysis Areas

Dependency Injection

• Spring XML: <bean> definitions in XML config
• Spring Annotations: @Autowired, @Component, @Service
• CDI (Java EE): @Inject, @Named, beans.xml
• EJB: @EJB injection

Data Access Patterns

• JDBC direct: DriverManager.getConnection, PreparedStatement
• JPA/Hibernate: @Entity, EntityManager, @PersistenceContext
• Spring Data: JpaRepository, CrudRepository interfaces
• MyBatis: @Mapper, XML SQL mappings

Web Service Patterns

• SOAP: @WebService, @WebMethod, WSDL files
• JAX-RS (REST): @Path, @GET, @POST, @Produces
• Spring MVC REST: @RestController, @RequestMapping

Authentication

• JAAS: LoginModule, jaas.conf
• Spring Security: WebSecurityConfigurerAdapter, @Secured
• Container-managed: web.xml security constraints, @RolesAllowed

Configuration Sources

• application.properties / application.yml (Spring)
• web.xml (Servlet config)
• JNDI lookups (InitialContext.lookup)
• System properties and environment variables

Migration Target Recommendations

Legacy Source	Recommended Target	Rationale
Servlets/JSP	Spring Boot MVC	Modern, well-supported, familiar patterns
EJB	Spring Boot services	CDI-like DI, simpler deployment
Struts	Spring Boot MVC	Direct action-to-controller mapping
JSF	Spring Boot + Thymeleaf or React	Server-side or SPA depending on complexity
SOAP services	Spring Boot REST	RESTful APIs are the modern standard
Java EE 7/8	Jakarta EE 10+ or Spring Boot 3	Either path viable, Spring Boot more common