跳至主要内容

JAX-RS 2.1: Reactive Client

Reactive Client

In JAXRS 2.0, a client to handle async resources looks like.
public class AsyncClient {

    public final static void main(String[] args) throws Exception {

        WebTarget target = ClientBuilder.newClient().target("http://localhost:8080/jaxrs-async/rest/ejb");

        Future<String> future = target.request()
                .async()
                .get(String.class);

        System.out.println("ejb resource future:" + future.get());

        target.request()
                .async()
                .get(AsyncClient.responseInvocationCallback());
    }

    private static InvocationCallback<Response> responseInvocationCallback() {
        return new InvocationCallback<Response>() {
            @Override
            public void completed(Response res) {
                System.out.println("Status:" + res.getStatusInfo());
                System.out.println("Entity:" + res.getEntity());
                System.out.println("Request success!");
            }

            @Override
            public void failed(Throwable e) {
                System.out.println("Request failed!");
            }

        };
    }

}
JAXRS 2.1 embraces the Reactive concept, added a rx() method switch to Reactive APIs and handle the response in stream.
By default, it supports Java 8 CompletionStage.
public class CompletionStageClient {

    public final static void main(String[] args) throws Exception {

        WebTarget target = ClientBuilder.newClient().target("http://localhost:8080/jaxrs-async/rest/ejb");

        CompletionStage<Void> future = target.request()
                .rx()
                .get(String.class)
                .thenAccept(t -> System.out.println(t));
              

    }
}
Jersey added extra support fro rxjava1.
public class ObservableClient {

    public final static void main(String[] args) throws Exception {
        Client client = ClientBuilder.newClient();
        
        client.register(RxObservableInvokerProvider.class);
        WebTarget target = client.target("http://localhost:8080/jaxrs-async/rest/ejb");

        target.request()
                .rx(RxObservableInvoker.class)
                .get(String.class)
                .subscribe(new Observer<String>() {
                    @Override
                    public void onCompleted() {
                        System.out.println("onCompleted");
                    }

                    @Override
                    public void onError(Throwable e) {
                        System.out.println("onError:" + e.getMessage());
                    }

                    @Override
                    public void onNext(String t) {
                        System.out.println("onNext:" + t);
                    }
                });

    }
}
And rxjava2.
public class FlowableClient {

    public final static void main(String[] args) throws Exception {
        Client client = ClientBuilder.newClient();

        client.register(RxFlowableInvokerProvider.class);
        WebTarget target = client.target("http://localhost:8080/jaxrs-async/rest/ejb");

        target.request()
                .rx(RxFlowableInvoker.class)
                .get(String.class)
                .subscribe(new Subscriber<String>() {

                    @Override
                    public void onError(Throwable e) {
                        System.out.println("onError:" + e.getMessage());
                    }

                    @Override
                    public void onNext(String t) {
                        System.out.println("onNext:" + t);
                    }

                    @Override
                    public void onSubscribe(Subscription s) {
                        System.out.println("onSubscribe:" + s);
                        s.request(1);                    
                    }

                    @Override
                    public void onComplete() {
                        System.out.println("onComplete");
                    }
                });

    }
}
And Guava's ListenableFuture.
public class ListenableFutureClient {

    public final static void main(String[] args) throws Exception {
        Client client = ClientBuilder.newClient();

        client.register(RxListenableFutureInvokerProvider.class);
        WebTarget target = client.target("http://localhost:8080/jaxrs-async/rest/ejb");

        ListenableFuture<String> future = target.request()
                .rx(RxListenableFutureInvoker.class)
                .get(String.class);

        FutureCallback<String> callback = new FutureCallback<String>() {
            @Override
            public void onSuccess(String result) {
                System.out.println("result :" + result);
            }

            @Override
            public void onFailure(Throwable t) {
                System.out.println("error :" + t.getMessage());
            }
        };

        Futures.addCallback(future, callback, Executors.newFixedThreadPool(10));

        System.out.println("ListenableFuture:" + future.get());

    }
}
Grab the source codes from my github account, and have a try.

评论

此博客中的热门博文

Create a restful application with AngularJS and Zend 2 framework

Create a restful application with AngularJS and Zend 2 framework This example application uses AngularJS/Bootstrap as frontend and Zend2 Framework as REST API producer. The backend code This backend code reuses the database scheme and codes of the official Zend Tutorial, and REST API support is also from the Zend community. Getting Started with Zend Framework 2 Getting Started with REST and Zend Framework 2 Zend2 provides a   AbstractRestfulController   for RESR API producing. class AlbumController extends AbstractRestfulController { public function getList() { $results = $this->getAlbumTable()->fetchAll(); $data = array(); foreach ($results as $result) { $data[] = $result; } return new JsonModel(array( 'data' => $data) ); } public function get($id) { $album = $this->getAlbumTable()->getAlbum($id); return new JsonModel(array("data" =...

Build a Reactive application with Angular 5 and Spring Boot 2.0

I have created a post to describe Reactive programming supports in Spring 5 and its subprojects, all codes of this article are updated the latest Spring 5 RELEASE, check spring-reactive-sample under my Github account. In this post, I will create a simple blog system, including: A user can sign in and sign out. An authenticated user can create a post. An authenticated user can update a post. Only the user who has ADMIN role can delete a post. All users(including anonymous users) can view post list and post details. An authenticated user can add his comments to a certain post. The backend will be built with the latest Spring 5 reactive stack, including: Spring Boot 2.0, at the moment the latest version is 2.0.0.M7 Spring Data MongoDB supports reactive operations for MongoDB Spring Session adds reactive support for WebSession Spring Security 5 aligns with Spring 5 reactive stack The frontend is an Angular based SPA and it will be generated by Angular CLI. The so...

JPA 2.1: Attribute Converter

JPA 2.1: Attribute Converter If you are using Hibernate, and want a customized type is supported in your Entity class, you could have to write a custom Hibernate Type. JPA 2.1 brings a new feature named attribute converter, which can help you convert your custom class type to JPA supported type. Create an Entity Reuse the   Post   entity class as example. @Entity @Table(name="POSTS") public class Post implements Serializable { private static final long serialVersionUID = 1L; @Id @GeneratedValue(strategy = GenerationType.AUTO) @Column(name="ID") private Long id; @Column(name="TITLE") private String title; @Column(name="BODY") private String body; @Temporal(javax.persistence.TemporalType.DATE) @Column(name="CREATED") private Date created; @Column(name="TAGS") private List<String> tags=new ArrayList<>(); } Create an attribute convert...