how to send json object from REST client using javax.ws.rs.client.WebTarget

Question

I have a POJO given below which I want to PUT to the server as JSON or XML.

This is what I have done

CLIENT:

ClientConfig config = new ClientConfig();
Client client = ClientBuilder.newClient(config);
WebTarget target = client.target(getBaseURI());

public void putFriend(String uri , Friend friend)
{
    System.out.println(friend.toString());

    target = target.path(some_path).path(uri);
    ClientResponse response =        target.request(MediaType.APPLICATION_JSON).put(Entity.entity(friend,MediaType.APPLICATION_JSON),ClientResponse.class);
}

Examples I found on web were using WebResource.

I don't know how to do using WebTarget. What I have done is taken from some example found on SO but Entity.entity() gives error undefined method entity(friend, String).

POJO

@XmlRootElement
public class Friend{

    private String friendURI;
    private String event;
    private String uri;

    String getUri() {
        return uri;
    }
    void setUri(String uri) {
        this.uri = uri;
    }
    String getFriendURI() {
        return friendURI;
    }
    void setFriendURI(String friendURI) {
        this.friendURI = friendURI;
    }
    String getEvent() {
        return event;
    }
    void setEvent(String event) {
        this.event = event;
    }
public String toString() {
        return "Friend [friendURI=" + friendURI + ", uri=" + uri + ", event=" + event
                 + "]";
}

Please guide how to do this.

Thanks

Solution

There are two different Jersey major versions, 1.x and 2.x, You seems to be trying to use a combination of both, which won't work. The 2.x versions don't have some classes as in 1.x and vice versa.

If you want to use Jersey 2.x, then you should be using Response, rather than ClientResponse

Response response = target.request().put(Entity.json(friend));
                                        // .json == automatic 'application/json'

• See Working with the Client API for 2.x
• Also as mentioned in your previous post, the getters and setters should be public for the Friend class
• Also see the WebTarget API

Basic breakdown.

• Calling request() on WebTarget returns an Invocation.Buidler

  Invocation.Builder builder = target.request();
  

• Once we call put, we get back a Response

  Response response = builder.put(Entity.json(friend));
  

• To extract a known type from the response, we could use readEntity(Class type)

  String responseString = response.readEntity(String.class);
  response.close();
  

Comments

[user3275095]

Thanks a lot for helping me every time. Entity.json(friend) gives error that method not define json(friend).

[Paul Samsotha]

Make sure Entity is javax.ws.rs.client.Entity

[user3275095]

Oh sorry, wrong Entity class was imported. Corrected that. Thanks. And yes getters and setters are public. Just copied the code from older post.

[user3275095]

One more thing, you explain really well. Thumbs up for that. Do you have any blog or website? It would be really helpful for newbies. Otherwise I guess I know who to meet :).

[seleniumlover]

Thank you very much peeskillet. Could you also show the example where you could use the access token as header in the request after getting it from the Oauth2 process and do the post request for login?

[Sabarish]

For simple, key value pair, we can use Map and use Entity.json(mapObj).

[Salman Shaikh]

I have a API which is developed in spring boot , I am trying to hit that API, and I have passed my POJO object in the Entity.json , but it is not getting mapped with Object there in the API. I am getting 400 from my API , which I send when the parameters are not present. What might be the issue.

[Paul Samsotha]

@SalmanShaikh Please post another question on SO. I cannot tell without seeing some code.

[Atul Kumar]

String responseString = response.readEntity(String.class); response.close(); : this line save me