What s new in Spring? Craig

Transcription

1 What s new in Spring? Craig Walls

2 What s new? The Spring Ecosystem Compatibility Concerns Configuration Improvements REST WebSocket/STOMP Spring 4.1

3 WebSocket, STOMP (and some other stuff that s new in Spring) Craig Walls

4 What s new in the greater Spring Ecosystem?

5 New website

6 Spring IO

7 Spring Boot Auto-configuration Dependency starters Groovy CLI Actuator This is a **complete** Spring class App String home() { "Hi"

8 Spring Security and @EnableWebMvcSecurity protected void configure(httpsecurity http) throws Exception { http public class WebSecurityConfiguration extends public class SecurityConfig extends private public void registerauthentication(authenticationmanagerbuilder auth) throws Exception auth.loginpage("/login"); public class WebSecurityConfiguration extends WebSecurityConfigurerAdapter public void registerauthentication(authenticationmanagerbuilder auth) throws Exception { auth.jdbcauthentication().datasource(datasource).usersbyusernamequery("select username, password, enabled from myapp_users where username=?").authoritiesbyusernamequery("select username, authority from myapp_auths where username=?");

9 Spring Data REST & ALPS Spring Data produces repository implementations Spring Data REST produces REST APIs (with HAL linking) Spring Data REST will provide ALPS metadata

10 JSON Patch and Differential Sync How to handle PATCH requests in Spring MVC? JSON Patch to describe resource diffs Differential Synchronization for live updates

11 Compatibility

12 Java 8 support Lambdas and method references for Spring callback interfaces java.time support Parameter name discovery Annotations retrofitted Compatible with Java 6 and 7

13 Java 8 lambda support public List<Book> findallbooks() { return jdbc.query( public List<Book> findallbooks() { "select isbn, title, return author jdbc.query( from books", new RowMapper<Book>() "select { isbn, title, author from books", public Book maprow(resultset (rs, rownum) -> rs, { int rownum) throws java.sql.sqlexception { return new Book( return new Book( rs.getstring("isbn"), rs.getstring("isbn"), rs.getstring("title"), rs.getstring("title"), rs.getstring("author")); rs.getstring("author")); ; ); );

14 JavaEE 6 and 7 Java EE 6 is now the baseline JPA 2.0 / Servlet 3.0 Servlet 2.5 supported (for the sake of GAE) Servlet 3.0+ recommended

15 Configuration

16 public class ThymeleafConfig public SpringTemplateEngine templateengine(templateresolver templateresolver) { SpringTemplateEngine templateengine = new SpringTemplateEngine(); templateengine.settemplateresolver(templateresolver); public class ThymeleafCondition implements Condition { return templateengine; public boolean matches(conditioncontext context, AnnotatedTypeMetadata metadata) { try context.getclassloader().loadclass( public ThymeleafViewResolver "org.thymeleaf.spring4.springtemplateengine"); viewresolver( SpringTemplateEngine templateengine) { return true; ThymeleafViewResolver viewresolver = new ThymeleafViewResolver(); catch viewresolver.settemplateengine(templateengine); (ClassNotFoundException e) { return return false; viewresolver; public TemplateResolver templateresolver() { TemplateResolver templateresolver = new ServletContextTemplateResolver(); templateresolver.setprefix("/web-inf/views/"); templateresolver.setsuffix(".html"); templateresolver.settemplatemode("html5"); return templateresolver;

17 Generics as public class GenericQualifierConfig public Thing<String> stringthing() { return new public Thing<Integer> intthing() { return new public ThingKeeper(Thing<String> stringthing, Thing<Integer> intthing) { this.stringthing = stringthing; this.intthing = intthing;

18 Ordered public class public Shooter greedo() { return public Shooter han() { return new Shooter("Han public class Shooters { private List<Shooter> public Shooters(List<Shooter> shooters) { this.shooters = shooters; public List<Shooter> getshooters() { return shooters;

19 Meta-annotations ElementType.TYPE) key="#id") SlowTransactionalService isolation=isolation.repeatable_read) Propagation propagation(); SlowTransactionalService { Isolation isolation(); String key();

20 Groovy configuration import com.habuma.spring4fun.foo; import com.habuma.spring4fun.bar; beans { bar(bar) { name = "Cheers" foo(foo) { bar = bar GenericGroovyApplicationContext appcontext = new GenericGroovyApplicationContext("com/habuma/spring4fun/beans.groovy");

21 Thing bean") public class production data source") public DataSource datasource() at public void setdatasource(datasource ds) { CGLib proxies no longer require a default constructor

22 REST

23 Simpler @RestController public class BookController public class @RequestMapping(method=RequestMethod.GET) public List<Book> allbooks()... public List<Book> allbooks() public Book bookbyisbn(@pathvariable String isbn) {... public Book bookbyisbn(@pathvariable String method=requestmethod.get) public List<Book> search(@requestparam("q") String query) public List<Book> search(@requestparam("q") String query) {...

24 Asynchronous REST clients AsyncRestTemplate rest = new AsyncRestTemplate(); ListenableFuture<ResponseEntity<Profile>> future = RestTemplate rest.getforentity(" = new RestTemplate(); Profile.class); ResponseEntity<Profile> response = future.addcallback(new rest.getforentity(" ListenableFutureCallback<ResponseEntity<Profile>>() Profile.class); { public void onsuccess(responseentity<profile> response) {... ; public void onfailure(throwable throwable) {... );

25 WebSocket/STOMP

26 What is WebSocket? Full duplex communication channel Enables the server to talk to the browser* * What you really want to do

27 How Spring supports WebSocket Low-level API SockJS support Higher-level Spring MVC-based API Messaging template

28 The problem with WebSocket It s not ubiquitous Browser support iffy Server support iffy Proxy server support iffy

29 Introducing SockJS WebSocket emulator Mirrors WebSocket API closely Tries WebSocket first Falls back to XHR Streaming, XDR Streaming, IFrame Event Source, IFrame HTML File, XHR Polling, XDR Polling, IFrame XHR Polling, JSONP Polling

30 More problems with WebSocket Too low-level No messaging semantics

31 Introducing STOMP Simple Text Oriented Messaging Protocol Offers HTTP-like message semantics SEND destination:/app/marco content-length:20 {\"message\":\"marco\" Emphasis on messaging More akin to JMS and AMQP Subscribe/send, not request/response

32 public class WebSocketStompConfig extends AbstractWebSocketMessageBrokerConfigurer public void registerstompendpoints(stompendpointregistry registry) { public void configuremessagebroker(messagebrokerregistry registry) { registry.enablesimplebroker("/queue/", "/topic/"); registry.setapplicationdestinationprefixes("/app");

33 Simple broker message flow

34 Enabling STOMP over a public class WebSocketStompConfig extends AbstractWebSocketMessageBrokerConfigurer public void registerstompendpoints(stompendpointregistry registry) { public void configuremessagebroker(messagebrokerregistry registry) { registry.enablestompbrokerrelay("/queue/", "/topic/"); registry.setapplicationdestinationprefixes("/app");

35 Broker relay message flow

36 Handling public class MarcoController { private static final Logger logger = public Shout handleshout(shout incoming) { logger.info("received message: " + incoming.getmessage()); try { Thread.sleep(2000); catch (InterruptedException e) { Shout outgoing = new Shout(); outgoing.setmessage("polo"); return outgoing;

37 Handling public class GamedayScoresController public List<Score> scores() {

38 Handling public class MarcoController { private static final Logger logger public Shout handleexception(throwable t) { Shout s = new Shout(); s.setmessage("exception: " + t.getmessage()); return s;

39 Sending public class RandomNumberMessageSender { private SimpMessagingTemplate public RandomNumberMessageSender(SimpMessagingTemplate messaging) { this.messaging = public void sendrandomnumber() { Shout random = new Shout(); random.setmessage("random # : " + (Math.random() * 100)); messaging.convertandsend("/topic/marco", random);

40 Freshly Picked: Spring 4.1

41 Spring MVC Improvements Static resource resolution/transformation Support for JSONP in controller methods support ResponseBodyAdvice java.util.optional support for method parameters DeferredResult can be returned GSon and Google Protocol Buffers message converters Improved web testing support

42 public class Views { public static class Public { public static class Privileged { public static class value= /users/{id ) UserProfile profile(@pathvariable( id ) long id) { return userrepo.findone(id); public class UserProfile String String String ssn;

43 private class JsonpAdvice extends AbstractJsonpResponseBodyAdvice { public JsonpAdvice() { super( callback );

44 Optional value="/books" ) List<Book> allbooks(optional<long> maxresults) { Long max = maxresults.ispresent()? maxresults.get() : Long.MAX_VALUE);

45 Caching Improvements CacheResolver public Book findbook(isbn isbn) { Operation-level book, keygenerator= mykeygenerator ) public Book findbook(isbn isbn) { Class-level book, keygenerator= mykeygenerator ) public class BookRepository { JCache integration

46 Thank you