Restcontroller in Java

Spring4 new features--web development enhancements

Spring4 new features-generic constrained dependency Injection

Spring4 new features-other improvements to the core container

Spring4 new features--web development enhancements

Starting with Spring4, Spring is developed with Servlet3, and if you use the Spring MVC test framework, you need to specify SERVLET3 compatible jar packages (because their mock objects are Servlet3 based). In addition, to facilitate rest development, the new @restcontroller is specified on the controller so that there is no need to add on each @requestmapping method @ResponseBody了。而且添加了一个 AsyncRestTemplate to support asynchronous nonblocking support for rest clients.

1. @RestController

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2. @RestController

4. Public class Usercontroller {

6. Private UserService UserService;

8. @Autowired

10. Public Usercontroller (UserService userservice) {

12. this. UserService = UserService;

14. }

16. @RequestMapping ("/test")

18. Public User view () {

20. User user = new user ();

22. User.setid (1L);

24. User.setname ("haha");

26. return user;

28. }

32. @RequestMapping ("/test2")

34. Public String View2 () {

36. return "{\" id\ ": 1}";

38. }

40. }

The implementation is to include @responsebody in the @ @RestController:

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1. @org. Springframework.stereotype.Controller

2. @org. springframework.web.bind.annotation.ResponseBody

3. Public @interface Restcontroller {

4. }

So when you develop the rest server side, the SPRING-MVC configuration file requires very little code, possibly just the following line:

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1. <context:component-scan base-package ="Com.sishuok.spring4"/>

2. <mvc:annotation-driven/>

2. Mvc:annotation-driven Configuration Changes

Unified style; Change Enablematrixvariables to Enable-matrix-variables property ; Change Ignoredefaultmodelonredirect to Ignore-default-model-on-redirect.

3, provide asyncresttemplate for client non-blocking asynchronous support.

3.1. Server-side

For server-side SPRINGMVC development, refer to the CHAPTER3-SPRINGMVC in Https://github.com/zhangkaitao/servlet3-showcase

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2. @RestController

4. Public class Usercontroller {

6. Private UserService UserService;

8. @Autowired

10. Public Usercontroller (UserService userservice) {

12. this. UserService = UserService;

14. }

16. @RequestMapping ("/api")

18. Public Callable<user> API () {

20. System.out.println ("=====hello");

22. return New Callable<user> () {

24. @Override

26. Public User call () throws Exception {

28. Thread.Sleep (10L * ); //Pause for two seconds

30. User user = new user ();

32. User.setid (1L);

34. User.setname ("haha");

36. return user;

38. }

40. };

42. }

44. }

Very simple, the server side pauses for 10 seconds and returns the result (but the server is also non-blocking). Refer to the code on my github for details.

3.2, the Client

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2. Public Static void Main (string[] args) {

4. Asyncresttemplate template = new asyncresttemplate ();

6. //return immediately after call (no blocking)

8. listenablefuture<responseentity<user>> future = template.getforentity ("http://localhost:9080/ Spring4/api ", User. class);

10. //Set asynchronous callbacks

12. Future.addcallback (new listenablefuturecallback<responseentity<user>> () {

14. @Override

16. Public void onsuccess (responseentity<user> result) {

18. System.out.println ("======client get Result:" + result.getbody ());

20. }

24. @Override

26. Public void onfailure (Throwable t) {

28. System.out.println ("======client failure:" + t);

30. }

32. });

34. System.out.println ("==no Wait");

36. }

The future is used here to do non-blocking, so we also need to give it a callback interface to get the results; the future and the callable are a pair, a consumption result, a result. When the template is finished, it returns immediately, does not block, and invokes its callback when there is a result.

Asyncresttemplate uses Simpleclienthttprequestfactory by default, which is achieved through java.net.HttpURLConnection, and we can also use Apache's HTTP Use Template.setasyncrequestfactory (new Httpcomponentsasyncclienthttprequestfactory ());

This article is from "Ghost" blog, please make sure to keep this source http://caizi.blog.51cto.com/5234706/1557325

Restcontroller in Java