Post empty body with Jersey 2 client

Question

How do I submit a post request with an empty body with a Jersey 2 client?

final MyClass result = ClientBuilder.newClient()
    .target("http://localhost:8080")
    .path("path")
    .queryParam("key", "value")
    .request(APPLICATION_JSON)
    .post(What to fill in here if the body should be left empty??, MyClass.class);

Update: this works:

final MyClass result = ClientBuilder
    .newBuilder().register(JacksonFeature).build()
    .target("http://localhost:8080")
    .path("path")
    .queryParam("key", "value")
    .request(APPLICATION_JSON)
    .post(null, MyClass.class);

I'm late to the party, but FWIW your update is the answer to my particular problem - specifically I don't want a Content-Type header :) — Oliver Charlesworth, Jun 13 '17 at 07:39

score 29 · Accepted Answer · answered Dec 14 '13 at 19:35

29

I can't find this in the doc's anywhere, but I believe you can use null to get an empty body:

final MyClass result = ClientBuilder.newClient()
    .target("http://localhost:8080")
    .path("path")
    .queryParam("key", "value")
    .request(APPLICATION_JSON)
    .post(Entity.json(null), MyClass.class)

answered Dec 14 '13 at 19:35

Alden

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I tried that but got a `MessageBodyProviderNotFoundException: MessageBodyWriter not found for media type=application/json,...`? – Stine Dec 14 '13 at 20:32
Well that's an entirely different problem... you should either register the default JacksonFeature, or write your own MessageBodyWriter/Reader – Alden Dec 14 '13 at 21:07
Ah I see you wrote that above, sorry. So `null` is the correct answer, right? – Alden Dec 14 '13 at 21:08
9

Thats stupid. Should be an Enity.empty() static method – Shervin Asgari Mar 18 '15 at 12:29
2

The problem with this approach is that jersey will still set the content-type header according to the Entity-factory (in this case `application/json`). – Hank Jul 16 '15 at 08:44
This works but I believe it does not send a 'Content-Length: 0' header... some endpoints apparently require a Content-Length if you send a POST. Is there a way to add a header manually? – Kevin Hooke Dec 09 '15 at 21:52
You can add headers between the request and post calls if you need to: `.request(APPLICATION_JSON).header(HttpHeaders.CONTENT_LENGTH, 0).post(Entity.json(null), MyClass.class)` – Alden Apr 07 '16 at 12:08
As @Hank points out this will make a request with the `Content-Type` set to `application/json` which might not be what you want. If you want to POST an empty form, try `post(Entity.form(new Form()))` – michiakig Mar 20 '17 at 17:52
It doesn't work for me. Entity.json("") works fine. – K. Gol Sep 03 '19 at 09:40

score 10 · Answer 2 · edited Sep 15 '16 at 22:30

10

I found that this worked for me:

Response r = client
    .target(url)
    .path(path)
    .queryParam(name, value)
    .request()
    .put(Entity.json(""));

Pass an empty string, not a null value.

edited Sep 15 '16 at 22:30

Scott Perham

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answered Sep 15 '16 at 21:43

Gapmeister66

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score 8 · Answer 3 · edited Jun 17 '17 at 17:35

8

I don't know if the version change it. But, the following doesn't work:

builder.put( Entity.json( null ) );

Where, the following works fine:

builder.put( Entity.json( "" ) );

edited Jun 17 '17 at 17:35

James Oravec

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answered Jun 25 '16 at 23:36

roanbaga

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3

This worked for me. I was trying to unit test where the parameter value comes through as `null`. I tried the `Entity.json("{}")` answer suggested but that gave me a parameter with an instance with every field `null` rather than the parameter which is what I wanted. – Chris R Nov 14 '19 at 13:07

score 3 · Answer 4 · answered May 09 '17 at 11:45

3

Just post an empty txt.

   .post(Entity.text(""));

answered May 09 '17 at 11:45

Emmanuel Osimosu

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score 0 · Answer 5 · edited Dec 18 '19 at 15:28

0

It worked for me only with an empty json object string

.post(Entity.json("{}")

All other solutions, still produced 400 Bad Request

P.S. The request is done using MediaType.APPLICATION_JSON

edited Dec 18 '19 at 15:28

svarog

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answered Mar 22 '18 at 09:59

Michael

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Post empty body with Jersey 2 client

5 Answers5