MVC 1.0 - by Example @ DevoxxUK 2016

Model-view-controller, or MVC for short, is a common pattern in web frameworks. MVC frameworks can be categorized as action-based or component-based. In a component-based framework, the HTTP requests are grouped and typically handled by framework components with little or no interaction with application code. In an action-based framework, on the other hand, the HTTP requests are routed to controllers and turned into actions by application code. The Java EE platform does not currently have support for action based MVC, but this is about to change. MVC 1.0, as specified by JSR 371, is targeted for the upcoming Java EE 8 release. This session provides an introduction to the action-based MVC 1.0 API and will include lots of code samples and tips to where to get started using this awesome technology.

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1. @ivar_grimstad #JSR371 MVC 1.0 - by Example Ivar Grimstad Principal Consultant
2. @ivar_grimstad #JSR371 - DevoxxUK 2016 @ivar_grimstad https://github.com/ivargrimstad https://www.linkedin.com/in/ivargrimstad http://lanyrd.com/profile/ivargrimstad/
3. @ivar_grimstad #JSR371 - DevoxxUK 2016 MVC
4. @ivar_grimstad #JSR371 - DevoxxUK 2016 Why?
5. @ivar_grimstad #JSR371 - DevoxxUK 2016 https://java.net/downloads/javaee-spec/JavaEE8_Community_Survey_Results.pdf
6. @ivar_grimstad #JSR371 - DevoxxUK 2016 http://glassfish.org/survey
7. @ivar_grimstad #JSR371 - DevoxxUK 2016 JSR 371 (MVC 1.0)
8. @ivar_grimstad #JSR371 - DevoxxUK 2016 JSR 371 Expert Group
9. @ivar_grimstad #JSR371 - DevoxxUK 2016 Action-based MVC
10. @ivar_grimstad #JSR371 - DevoxxUK 2016 Controller Model View Request Update Update
11. @ivar_grimstad #JSR371 - DevoxxUK 2016 Controller Model View Request Update Update
12. @ivar_grimstad #JSR371 - DevoxxUK 2016 Controller Model View Request Update Update
13. @ivar_grimstad #JSR371 - DevoxxUK 2016 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
14. @ivar_grimstad #JSR371 - DevoxxUK 2016 Existing Java EE Technologies
15. @ivar_grimstad #JSR371 - DevoxxUK 2016 Key Decisions
16. @ivar_grimstad #JSR371 - DevoxxUK 2016 Key Decisions
17. @ivar_grimstad #JSR371 - DevoxxUK 2016 Build MVC 1.0 on top of JAX-RS
18. @ivar_grimstad #JSR371 - DevoxxUK 2016 Controllers
19. @ivar_grimstad #JSR371 - DevoxxUK 2016 Controller public class HelloController { }
20. @ivar_grimstad #JSR371 - DevoxxUK 2016 Controller @Path(“hello”) public class HelloController { }
21. @ivar_grimstad #JSR371 - DevoxxUK 2016 Controller @Controller @Path(“hello”) public class HelloController { }
22. @ivar_grimstad #JSR371 - DevoxxUK 2016 Views
23. @ivar_grimstad #JSR371 - DevoxxUK 2016 View @Controller @Path(“hello”) public class HelloController { }
24. @ivar_grimstad #JSR371 - DevoxxUK 2016 View @Controller @Path(“hello”) public class HelloController { @GET public String hello() { return “hello.jsp”; } }
25. @ivar_grimstad #JSR371 - DevoxxUK 2016 View @Controller @Path(“hello”) public class HelloController { @GET public Viewable hello() { return new Viewable(“hello.jsp”); } }
26. @ivar_grimstad #JSR371 - DevoxxUK 2016 View @Controller @Path(“hello”) public class HelloController { @GET public Response hello() { return Response.status(OK).entity(“hello.jsp”).build(); } }
27. @ivar_grimstad #JSR371 - DevoxxUK 2016 View @Controller @Path(“hello”) public class HelloController { @View(“hello.jsp”) @GET public void hello() { } }
28. @ivar_grimstad #JSR371 - DevoxxUK 2016 View @View(“hello.jsp”) @Controller @Path(“hello”) public class HelloController { @GET public void hello() { } }
29. @ivar_grimstad #JSR371 - DevoxxUK 2016 Models
30. @ivar_grimstad #JSR371 - DevoxxUK 2016 Model @Named(“greeting”) @RequestScoped public class Greeting { private String message; public void setMessage(String message) { this.message = message; } public void getMessage() { return message; } }
31. @ivar_grimstad #JSR371 - DevoxxUK 2016 Model @View(“hello.jsp”) @Controller @Path(“hello”) public class HelloController { @GET public void hello() { } }
32. @ivar_grimstad #JSR371 - DevoxxUK 2016 Model @View(“hello.jsp”) @Controller @Path(“hello”) public class HelloController { @Inject private Greeting greeting; @GET public void hello() { greeting.setMessage(“Hello Devoxx!”); } }
33. @ivar_grimstad #JSR371 - DevoxxUK 2016 Model <%@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>
34. @ivar_grimstad #JSR371 - DevoxxUK 2016 Model @View(“hello.jsp”) @Controller @Path(“hello”) public class HelloController { @GET public void hello() { } }
35. @ivar_grimstad #JSR371 - DevoxxUK 2016 Model @View(“hello.jsp”) @Controller @Path(“hello”) public class HelloController { @Inject private Models model; @GET public void hello() { model.put(“message”, “Hello Devoxx!”); } }
36. @ivar_grimstad #JSR371 - DevoxxUK 2016 Model <%@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>
37. @ivar_grimstad #JSR371 - DevoxxUK 2016 Validation
38. @ivar_grimstad #JSR371 - DevoxxUK 2016 @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.
39. @ivar_grimstad #JSR371 - DevoxxUK 2016 Validation 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(); } }
40. @ivar_grimstad #JSR371 - DevoxxUK 2016 @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
41. @ivar_grimstad #JSR371 - DevoxxUK 2016 BindingResult
42. @ivar_grimstad #JSR371 - DevoxxUK 2016 View Engines
43. @ivar_grimstad #JSR371 - DevoxxUK 2016 Bring Your Own View Engine
44. @ivar_grimstad #JSR371 - DevoxxUK 2016 ViewEngine public interface ViewEngine { boolean supports(String view); void processView(ViewEngineContext context) throws ViewEngineException; }
45. @ivar_grimstad #JSR371 - DevoxxUK 2016 View Engine Conflicts @Priority(OUTRAGEOSLY_HIGH)
 @ApplicationScoped
 public class FreemarkerViewEngine extends ViewEngineBase { … }
46. @ivar_grimstad #JSR371 - DevoxxUK 2016 Events
47. @ivar_grimstad #JSR371 - DevoxxUK 2016 BeforeControllerEvent AfterControllerEvent BeforeProcessViewEvent AfterProcessViewEvent ControllerRedirectEvent
48. @ivar_grimstad #JSR371 - DevoxxUK 2016 Events Example @ApplicationScoped public class EventObserver { void onBeforeController(@Observes BeforeControllerEvent e) { println("URI: " + e.getUriInfo().getRequestURI()); } void onAfterController(@Observes AfterControllerEvent e) { println("Controller: " + e.getResourceInfo().getResourceMethod()); } }
49. @ivar_grimstad #JSR371 - DevoxxUK 2016 Security
50. @ivar_grimstad #JSR371 - DevoxxUK 2016 Cross Site Request Forgery @Controller @Path(“csrf”) public class HelloController { @CsrfValid @POST public Response post(@FormParam(“greeting") String greet { } }
51. @ivar_grimstad #JSR371 - DevoxxUK 2016 Cross Site Request Forgery <%@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>
52. @ivar_grimstad #JSR371 - DevoxxUK 2016 Scopes
53. @ivar_grimstad #JSR371 - DevoxxUK 2016 Model ReservationCtl Update confirmation reservation OK Browser POST
54. @ivar_grimstad #JSR371 - DevoxxUK 2016 Model ReservationCtl Access Update ConfirmationCtl GET confirmation reservation OK Redirect Browser POST
55. @ivar_grimstad #JSR371 - DevoxxUK 2016 @RedirectScoped @Named(“greeting”) @RedirectScoped public class Greeting { private String message; public void setMessage(String message) { this.message = message; } public void getMessage() { return message; } }
56. @ivar_grimstad #JSR371 - DevoxxUK 2016 @Controller public class HelloController { @Inject private Greeting greeting; @POST @Path(“from”) public String hello() { greeting.setMessage(“Hello Devoxx!”); return “redirect:/to“; } } @RedirectScoped @RedirectScoped @RequestScoped
57. @ivar_grimstad #JSR371 - DevoxxUK 2016 @Controller public class HelloController { @Inject private Greeting greeting; @POST @Path(“to”) public String hello() { return “here.jsp“; } } @RedirectScoped Same Bean
58. @ivar_grimstad #JSR371 - DevoxxUK 2016 Tired of slides?
59. @ivar_grimstad #JSR371 - DevoxxUK 2016 Show me the CODE !
60. @ivar_grimstad #JSR371 - DevoxxUK 2016 Tool Support
61. @ivar_grimstad #JSR371 - DevoxxUK 2016 JPA Modeler jpamodeler.github.io/ Gaurav Gupta @jGauravGupta
62. @ivar_grimstad #JSR371 - DevoxxUK 2016 MVC 1.0 Logical View https://github.com/GeertjanWielenga/BasicMVCSupport Geertjan Wielenga @GeertjanW
63. @ivar_grimstad #JSR371 - DevoxxUK 2016 Summary
64. @ivar_grimstad #JSR371 - DevoxxUK 2016 Action-based MVC
65. @ivar_grimstad #JSR371 - DevoxxUK 2016 Existing Java EE Technologies
66. @ivar_grimstad #JSR371 - DevoxxUK 2016 Build MVC 1.0 on top of JAX-RS
67. @ivar_grimstad #JSR371 - DevoxxUK 2016 Project Page https://java.net/projects/mvc-spec GitHub https://github.com/mvc-spec Reference Implementation https://ozark.java.net
68. @ivar_grimstad #JSR371 - DevoxxUK 2016 Samples https://github.com/ivargrimstad/mvc-samples Blog http://www.agilejava.eu/
69. @ivar_grimstad #JSR371 - DevoxxUK 2016 cybercom.com