MVC 1.0 - by Example @ Devoxx Belgium 2015

Joint presentation with René Gielen

Transcript

1. @rgielen / @ivar_grimstad #Devoxx #JSR371 JSR 371 MVC 1.0 for Java EE 8
2. @rgielen / @ivar_grimstad #Devoxx #JSR371 Ivar Grimstad Principal Consultant for Cybercom Sweden JSR 371 Expert Group Member
3. @rgielen / @ivar_grimstad #Devoxx #JSR371 René Gielen Independent Software Craftsman, Consultant, Trainer Apache Struts PMC Chair
4. @rgielen / @ivar_grimstad #Devoxx #JSR371
5. @rgielen / @ivar_grimstad #Devoxx #JSR371 Front Controller
6. @rgielen / @ivar_grimstad #Devoxx #JSR371 Action
7. @rgielen / @ivar_grimstad #Devoxx #JSR371 Request
8. @rgielen / @ivar_grimstad #Devoxx #JSR371 Response
9. @rgielen / @ivar_grimstad #Devoxx #JSR371 Serious Business
10. @rgielen / @ivar_grimstad #Devoxx #JSR371
11. @rgielen / @ivar_grimstad #Devoxx #JSR371
12. @rgielen / @ivar_grimstad #Devoxx #JSR371 Action vs. Component Component based Complex Stateful Components Abstract away Request-Response Action based Abstract away Technical Details of HTTP Stateless Embrace Request-Response
13. @rgielen / @ivar_grimstad #Devoxx #JSR371
14. @rgielen / @ivar_grimstad #Devoxx #JSR371 Introduction to JSR 371
15. @rgielen / @ivar_grimstad #Devoxx #JSR371 Why?
16. @rgielen / @ivar_grimstad #Devoxx #JSR371 https://java.net/downloads/javaee-spec/JavaEE8_Community_Survey_Results.pdf
17. @rgielen / @ivar_grimstad #Devoxx #JSR371 http://glassfish.org/survey
18. @rgielen / @ivar_grimstad #Devoxx #JSR371 Action-based MVC
19. @rgielen / @ivar_grimstad #Devoxx #JSR371 Existing Java EE Technologies
20. @rgielen / @ivar_grimstad #Devoxx #JSR371 JSR 371 Expert Group
21. @rgielen / @ivar_grimstad #Devoxx #JSR371 Key Decisions
22. @rgielen / @ivar_grimstad #Devoxx #JSR371 Key Decisions
23. @rgielen / @ivar_grimstad #Devoxx #JSR371 Build MVC 1.0 on top of JAX-RS
24. @rgielen / @ivar_grimstad #Devoxx #JSR371 Show me the CODE !
25. @rgielen / @ivar_grimstad #Devoxx #JSR371 Controllers
26. @rgielen / @ivar_grimstad #Devoxx #JSR371 public class HelloController { } Controller
27. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Path(“hello”) public class HelloController { } Controller
28. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Controller @Path(“hello”) public class HelloController { } Controller
29. @rgielen / @ivar_grimstad #Devoxx #JSR371 Views
30. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Controller @Path(“hello”) public class HelloController { } View
31. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Controller @Path(“hello”) public class HelloController { @GET public String hello() { return “hello.jsp”; } } View
32. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Controller @Path(“hello”) public class HelloController { @GET public Viewable hello() { return new Viewable(“hello.jsp”); } } View
33. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Controller @Path(“hello”) public class HelloController { @GET public Response hello() { return Response.status(OK).entity(“hello.jsp”).build(); } } View
34. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Controller @Path(“hello”) public class HelloController { @View(“hello.jsp”) @GET public void hello() { } } View
35. @rgielen / @ivar_grimstad #Devoxx #JSR371 @View(“hello.jsp”) @Controller @Path(“hello”) public class HelloController { @GET public void hello() { } } View
36. @rgielen / @ivar_grimstad #Devoxx #JSR371 Models
37. @rgielen / @ivar_grimstad #Devoxx #JSR371 @View(“hello.jsp”) @Controller @Path(“hello”) public class HelloController { @GET public void hello() { } } Model
38. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Named(“greeting”) @RequestScoped public class Greeting { private String message; public void setMessate(String message) { this.message = message; } public void getMessage() { return message; } } Model
39. @rgielen / @ivar_grimstad #Devoxx #JSR371 @View(“hello.jsp”) @Controller @Path(“hello”) public class HelloController { @Inject private Greeting greeting; @GET public void hello() { greeting.setMessage(“Hello Devoxx!”); } } Model
40. @rgielen / @ivar_grimstad #Devoxx #JSR371 <%@page contentType=“text/html" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <title>MVC 1.0 Hello Demo</title> </head> <body> <h1>Hello ${greeting.message}</h1> </body> </html> Model
41. @rgielen / @ivar_grimstad #Devoxx #JSR371 @View(“hello.jsp”) @Controller @Path(“hello”) public class HelloController { @GET public void hello() { } } Model
42. @rgielen / @ivar_grimstad #Devoxx #JSR371 @View(“hello.jsp”) @Controller @Path(“hello”) public class HelloController { @Inject private Models model; @GET public void hello() { model.put(“message”, “Hello Devoxx!”); } } Model
43. @rgielen / @ivar_grimstad #Devoxx #JSR371 <%@page contentType=“text/html" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <title>MVC 1.0 Hello Demo</title> </head> <body> <h1>Hello ${message}</h1> </body> </html> Model
44. @rgielen / @ivar_grimstad #Devoxx #JSR371 View Engines
45. @rgielen / @ivar_grimstad #Devoxx #JSR371 Bring Your Own View Engine BYOVE
46. @rgielen / @ivar_grimstad #Devoxx #JSR371 public interface ViewEngine { boolean supports(String view); void processView(ViewEngineContext context) throws ViewEngineException; } ViewEngine
47. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Priority(OUTRAGEOSLY_HIGH)
 @ApplicationScoped
 public class FreemarkerViewEngine extends ViewEngineBase { … } View Engine Conflicts
48. @rgielen / @ivar_grimstad #Devoxx #JSR371 Validation
49. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Controller @Path("form") public class FormController { @POST public Response formPost(@Valid @BeanParam FormDataBean f) { return Response.status(OK).entity(“data.jsp”).build(); } } Validation ConstraintValidationException @Min, @NotNull etc.
50. @rgielen / @ivar_grimstad #Devoxx #JSR371 public class FormViolationMapper implements ExceptionMapper<ConstraintViolationException> { public Response toResponse(ConstraintViolationException e) { Set<ConstraintViolation<?>> s =e.getConstraintViolations(); // process violations ... return Response.status(BAD_REQUEST) .entity(“error.jsp”).build(); } } Validation
51. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Controller @Path("form") public class FormController { @Inject private BindingResult br; @POST public Response formPost(@Valid @BeanParam FormDataBean f) { if (br.isFailed()) { return Response.status(BAD_REQUEST) .entity(“error.jsp”).build(); } return Response.status(OK).entity(“data.jsp”).build(); } } Validation Allows for MVC Error Handling
52. @rgielen / @ivar_grimstad #Devoxx #JSR371 Scopes
53. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Named(“greeting”) @RedirectScoped public class Greeting { private String message; public void setMessate(String message) { this.message = message; } public void getMessage() { return message; } } @RedirectScoped
54. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Controller public class HelloController { @Inject private Greeting greeting; @POST @Path(“from”) public String hello() { greeting.setMessage(“Hello Devoxx!”); return “redirect:/to“; } } @RedirectScoped @RedirectScoped @RequestScoped
55. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Controller public class HelloController { @Inject private Greeting greeting; @POST @Path(“to”) public String hello() { return “here.jsp“; } } @RedirectScoped Same Bean
56. @rgielen / @ivar_grimstad #Devoxx #JSR371 Security
57. @rgielen / @ivar_grimstad #Devoxx #JSR371 @Controller @Path(“csrf”) public class HelloController { @CsrfValid @POST public Response post(@FormParam(“greeting") String greet { } } Cross Site Request Forgery
58. @rgielen / @ivar_grimstad #Devoxx #JSR371 <%@page contentType=“text/html" pageEncoding="UTF-8"%> <!DOCTYPE html> <html> <head> <title>MVC 1.0 Hello Demo</title> </head> <body> <form action="csrf" method="post" accept-charset="utf-8"> <input type="submit" value="Click here"/> <input type="hidden" name="${mvc.csrf.name}" value="${mvc.csrf.token}"/> </form> </body> </html> Cross Site Request Forgery
59. @rgielen / @ivar_grimstad #Devoxx #JSR371 Events
60. @rgielen / @ivar_grimstad #Devoxx #JSR371 BeforeControllerEvent AfterControllerEvent BeforeProcessViewEvent AfterProcessViewEvent ControllerRedirectEvent Currently Supported Events
61. @rgielen / @ivar_grimstad #Devoxx #JSR371 @ApplicationScoped public class EventObserver { void onBeforeController(@Observes BeforeControllerEvent e) { println("URI: " + e.getUriInfo().getRequestURI()); } void onAfterController(@Observes AfterControllerEvent e) { println("Controller: " + e.getResourceInfo().getResourceMethod()); } } Events Example
62. @rgielen / @ivar_grimstad #Devoxx #JSR371 Summary
63. @rgielen / @ivar_grimstad #Devoxx #JSR371 Project Page https://java.net/projects/mvc-spec Mailing List users@mvc-spec.java.net Reference Implementation https://ozark.java.net
64. @rgielen / @ivar_grimstad #Devoxx #JSR371 JSR 371 - Test Drive
65. @rgielen / @ivar_grimstad #Devoxx #JSR371 How about Real World?
66. @rgielen / @ivar_grimstad #Devoxx #JSR371 Real World - Key Questions Common Problems Solved for Real World? On Par with comparable Servlet-based Frameworks?
67. @rgielen / @ivar_grimstad #Devoxx #JSR371 Comparable Frameworks Spring MVC around since 2005 “Real World” since 2008 (Spring 2.5 onward) today’s leader in Action-Land Struts 2 around since 2004 (WebWork 2) “Real World” since 2007 (Struts 2.0.9 onward) still widely adopted
68. @rgielen / @ivar_grimstad #Devoxx #JSR371 Comparable Frameworks Spring MVC around since 2005 “Real World” since 2008 (Spring 2.5 onward) today’s leader in Action-Land Struts 2 around since 2004 (WebWork 2) “Real World” since 2007 (Struts 2.0.9 onward) still widely adopted 3 Years till getting Real!
69. @rgielen / @ivar_grimstad #Devoxx #JSR371
70. @rgielen / @ivar_grimstad #Devoxx #JSR371 Let’s relax a bit… JSR 371: „Standing on the Shoulder of Giants“ JAX-RS / Jersey CDI Bean Validation Interceptors Facelets, Thymeleaf, Freemarker, Velocity Adds on Top Lightweight Top Layer Extension Points
71. @rgielen / @ivar_grimstad #Devoxx #JSR371 So - what are these “Common Problems“?
72. @rgielen / @ivar_grimstad #Devoxx #JSR371 “Hello MVC” is not enough!
73. @rgielen / @ivar_grimstad #Devoxx #JSR371 Common Real World Needs Scoped DI Controller Decoupling Controller Testability View Technology Flexibility VDL Expressiveness i18n / l10n Form Binding Type Conversion Declarative Validation Message Passing to View Post-Redirect-Get File Upload UI Controls and Theming AJAX Support Decorator Support Cross Cutting Concerns
74. @rgielen / @ivar_grimstad #Devoxx #JSR371 Scoped Dependency Injection Spring MVC Spring DI Struts 2 Supported Containers Supported Scopes EJB Support Spring MVC Spring DI Application, Session, Request, Redirect, Custom Yes (Adapter Framework) Struts 2 Spring DI, Guice, CDI Application, Session, Request, Redirect, Custom Yes (CDI) JSR 371 / Ozark CDI Application, Session, Request, Redirect, Custom Yes
75. @rgielen / @ivar_grimstad #Devoxx #JSR371 Controller Decoupling Spring MVC Spring DI Struts 2 Controllers as POJOs Coupling to Servlet API required Coupling to Servlet API supported Model Abstraction Spring MVC Yes No Yes Model Container, Return value Struts 2 Yes No Yes Controller Instance, Value Stack JSR 371 / Ozark Yes No Yes Scoped CDI Beans, Model Container
76. @rgielen / @ivar_grimstad #Devoxx #JSR371 Controller Testing Support Spring MVC Spring DI Struts 2 Unit Testing Mocking Support Integration Test Framework Spring MVC Easy Easy Spring Test MVC Struts 2 Easy Easy Struts 2 Test Framework JSR 371 / Ozark Easy Easy No / presumably Jersey Test Framework
77. @rgielen / @ivar_grimstad #Devoxx #JSR371 Supported View Technologies Spring MVC Spring DI Struts 2 JSP Templating DHTML Integration Others Spring MVC Yes Thymeleaf, Freemarker, Velocity, GSP Various 3rd Party Contributions JSON, XML, JasperReports Struts 2 Yes Freemarker, Velocity, Thymeleaf jQuery, Bootstrap, YUI AngularJS JSON, XML, JasperReports JSR 371 / Ozark Yes Facelets, Freemarker, Velocity, Thymeleaf Handlebars, Mustache JSON + XML (JAX-RS), AsciiDoc
78. @rgielen / @ivar_grimstad #Devoxx #JSR371 Real Code
79. @rgielen / @ivar_grimstad #Devoxx #JSR371 Wrap-up: State of MVC Lightweight Layer on Top of well established Technologies Easy to extend Addresses most Common Needs Some Gaps and Glitches most can easily addressed by Implementations and Extensions some might be gone in the final Specifications
80. @rgielen / @ivar_grimstad #Devoxx #JSR371 Q & A