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