What to use instead of org.jboss.resteasy.client.C

问题:

I just found that org.jboss.resteasy.client.ClientRequest is deprecated, invalidating everything I could find on Google about how to use the RESTEasy client. The Javadoc gives no indication as to what to use instead. Google is likewise silent.

I have reverted to 2.3.5 for now, but would be interested in the answer anyways, as well as how one was supposed to find out the answer without asking someone else who knew - is there a resource with that information where I could have looked ?

回答1:

The 3.0 beta documentation here describes these deprecations like so:

Resteasy manual client API, interceptors, StringConverters, StringParamterConverters, and Async HTTP APIs have all been deprecated and will be removed possibly in a later release. There is now a JAX-RS 2.0 equivalent for each of these things.

This would imply that the preferred method will be to use the JAX-RS Client API described in this post

回答2:

If we assume there is a JSON API at http://example.org/pizza/{id}.json, (where 'id' is a pizza ID) which returns results such as

{ 
  "name": "Hawaiian",
  "toppings": ["tomato", "ham", "cheese", "pineapple"]
}

Building on the Invocation.Builder Javadocs, we can do something like this,

import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Invocation;
import org.glassfish.jersey.jackson.JacksonFeature;

public class PizzaClient {
    private Client client;

    public PizzaClient() {
         client = ClientBuilder.newClient();
         // enable POJO mapping using Jackson - see
         // https://jersey.java.net/documentation/latest/user-guide.html#json.jackson
         client.register(JacksonFeature.class); 
    }

    /** POJO which maps to JSON results using Jackson */
    public static class Pizza {
        private String name;
        private String[] toppings;

        public String getName() { return name; }
        public String[] getToppings() { return toppings ; }
    }

    public Pizza getPizzaById(String id) {
        String uri = String.format("http://example.org/pizza/%s.json", id)
        Invocation.Builder bldr = client.target(uri).request("application/json");
        return bldr.get(Pizza.class);
    }

    public static void main(String[] args) {
       PizzaClient pc = new PizzaClient();
       Pizza pizza = pc.getPizzaById("1");
       System.out.println(pizza.getName() + ":");
       for (String topping : pizza.getToppings()) {
            System.out.println("\t" + topping);
       }
    }
}

(this is also assisted by this post although that uses the deprecated API).

Note also that you may need to register a special handler if you want to use Jackson to read POJOs (or, I think, using JAXB) as documented here

Update You actually only need the following Maven dependencies:

    <dependency>
        <groupId>org.glassfish.jersey.core</groupId>
        <artifactId>jersey-client</artifactId>
        <version>2.3.1</version>
    </dependency>
    <dependency>
        <groupId>org.glassfish.jersey.media</groupId>
        <artifactId>jersey-media-json-jackson</artifactId>
        <version>2.3.1</version>
    </dependency>

(In which case you're not using RestEasy at all -- the javax.ws.rs JAXRS implementation comes from Jersey)

OR you can stick with JBoss:

    <dependency>
        <groupId>org.jboss.resteasy</groupId>
        <artifactId>resteasy-jackson2-provider</artifactId>
        <version>3.0.4.Final</version>
    </dependency>
    <dependency>
        <groupId>org.jboss.resteasy</groupId>
        <artifactId>resteasy-client</artifactId>
        <version>3.0.4.Final</version>
    </dependency>

In which case you can just remove the JacksonFeature line in the above code, and the code uses the more liberal Apache licence.

回答3:

The RESTEasy documentation says we should close the client connection; that would be client.close() in your example. But every example I can find does not do this. Will the client connection get closed automatically during garbage collection?