struts-to-spring

# Struts 2 to Spring Boot 3.x Migration Guideline ## Metadata - **Source Technology**: Apache Struts 2 (struts2-core) - **Target Technology**: Spring Boot 3.x with Spring MVC - **Trigger Keywords**: struts, struts2, ActionSupport, struts.xml, xwork2, opensymphony, struts-tags - **Version**: 1.0.0 - **Last Updated**: 2025-01-22 ## Overview This guideline provides comprehensive skills for migrating Apache Struts 2 applications to Spring Boot 3.x. Each skill addresses a specific migration concern with concrete transformation rules, examples, and validation criteria. ## Skill Files | File | Skills | Description | |------|--------|-------------| | [SKILL-config.md](SKILL-config.md) | migrate-maven-dependencies, create-spring-boot-application, create-application-properties | Project setup and configuration | | [SKILL-action.md](SKILL-action.md) | convert-action-to-controller, convert-action-properties | Action to Controller conversion | | [SKILL-view.md](SKILL-view.md) | convert-jsp-tags, convert-ognl-to-el, convert-result-types | View layer migration | | [SKILL-interceptor.md](SKILL-interceptor.md) | convert-interceptor, convert-validation | Interceptors and validation | | [SKILL-xml.md](SKILL-xml.md) | migrate-struts-xml, migrate-web-xml | XML configuration migration | | [SKILL-test.md](SKILL-test.md) | convert-test-classes, create-exception-handler | Testing and exception handling | --- ## Migration Checklist Execute skills in this order: ### Phase 1: Project Setup 1. [ ] `migrate-maven-dependencies` - Update pom.xml ([SKILL-config.md](SKILL-config.md)) 2. [ ] `create-spring-boot-application` - Create main class ([SKILL-config.md](SKILL-config.md)) 3. [ ] `create-application-properties` - Create configuration ([SKILL-config.md](SKILL-config.md)) ### Phase 2: Configuration Migration 4. [ ] `migrate-struts-xml` - Plan controller structure ([SKILL-xml.md](SKILL-xml.md)) 5. [ ] `migrate-web-xml` - Remove Struts filter ([SKILL-xml.md](SKILL-xml.md)) ### Phase 3: Action Conversion 6. [ ] `convert-action-to-controller` - Convert each Action class ([SKILL-action.md](SKILL-action.md)) 7. [ ] `convert-action-properties` - Handle Action properties ([SKILL-action.md](SKILL-action.md)) ### Phase 4: Cross-cutting Concerns 8. [ ] `convert-validation` - Migrate validation logic ([SKILL-interceptor.md](SKILL-interceptor.md)) 9. [ ] `convert-interceptor` - Convert interceptors ([SKILL-interceptor.md](SKILL-interceptor.md)) ### Phase 5: View Layer 10. [ ] `convert-result-types` - Handle result mappings ([SKILL-view.md](SKILL-view.md)) 11. [ ] `convert-jsp-tags` - Update JSP files ([SKILL-view.md](SKILL-view.md)) 12. [ ] `convert-ognl-to-el` - Fix expressions ([SKILL-view.md](SKILL-view.md)) ### Phase 6: Testing & Polish 13. [ ] `convert-test-classes` - Update tests ([SKILL-test.md](SKILL-test.md)) 14. [ ] `create-exception-handler` - Global exception handling ([SKILL-test.md](SKILL-test.md)) --- ## Complete Transformation Example ### Before (Struts) **HelloAction.java:** ```java package com.example.action; import com.opensymphony.xwork2.ActionSupport; public class HelloAction extends ActionSupport { private String name; private String message; public String execute() { if (name == null || name.isEmpty()) { return INPUT; } message = "Hello, " + name + "!"; return SUCCESS; } public void validate() { if (name != null && name.length() > 50) { addFieldError("name", "Name too long"); } } // getters and setters public String getName() { return name; } public void setName(String name) { this.name = name; } public String getMessage() { return message; } } ``` **struts.xml:** ```xml <action name="hello" class="com.example.action.HelloAction"> <result name="success">/WEB-INF/jsp/hello.jsp</result> <result name="input">/WEB-INF/jsp/hello-form.jsp</result> </action> ``` **hello.jsp:** ```jsp <%@ taglib prefix="s" uri="/struts-tags" %> <html> <body> <s:property value="message"/> </body> </html> ``` ### After (Spring Boot) **HelloForm.java:** ```java package com.example.form; import jakarta.validation.constraints.NotBlank; import jakarta.validation.constraints.Size; public class HelloForm { @NotBlank(message = "Name is required") @Size(max = 50, message = "Name too long") private String name; public String getName() { return name; } public void setName(String name) { this.name = name; } } ``` **HelloController.java:** ```java package com.example.controller; import com.example.form.HelloForm; import jakarta.validation.Valid; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.validation.BindingResult; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.ModelAttribute; import org.springframework.web.bind.annotation.PostMapping; @Controller public class HelloController { @GetMapping("/hello") public String showForm(Model model) { model.addAttribute("helloForm", new HelloForm()); return "hello-form"; } @PostMapping("/hello") public String execute(@Valid @ModelAttribute HelloForm form, BindingResult result, Model model) { if (result.hasErrors()) { return "hello-form"; } String message = "Hello, " + form.getName() + "!"; model.addAttribute("message", message); return "hello"; } } ``` **hello.jsp:** ```jsp <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <html> <body> ${message} </body> </html> ``` **Application.java:** ```java package com.example; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class Application { public static void main(String[] args) { SpringApplication.run(Application.class, args); } } ``` **application.properties:** ```properties server.port=8080 spring.mvc.view.prefix=/WEB-INF/jsp/ spring.mvc.view.suffix=.jsp ```