[BUG][Java] ApiClient.java: error: no suitable method found for create(byte[],MediaType)

[toby-murray-snow-software]

Bug Report Checklist

• Have you provided a full/minimal spec to reproduce the issue?
• Have you validated the input using an OpenAPI validator (example)?
• Have you tested with the latest master to confirm the issue still exists?
• Have you searched for related issues/PRs?
• [] What's the actual output vs expected output?
• [Optional] Sponsorship to speed up the bug fix or feature request (example)

Description

Using the java generator against a basic spec, the generated project fails to compile.

openapi-generator version

5.1.0 and latest master (docker image 3c6b0382cd49)

Regression from 5.0.1

OpenAPI declaration file content or url

openapi: 3.0.0
info:
  version: 1.0.0
  title: Api

paths:
  /version:
    get:
      tags:
      - version
      summary: Gets the system version check
      operationId: getVersion
      responses:
        200:
          description: Success
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/VersionGetResponse'

components:
  schemas:
    VersionGetResponse:
      type: string
      description: The version of this service
      required:
        - status
      properties:
        status:
          type: string
          description: OK

Generation Details

java -jar openapi-generator-cli-5.1.0.jar generate -g java -i service.yaml

Steps to reproduce

1. Run the generator as described above
2. Try to compile the code with ./gradlew compileJava or similar

Expected:

It will compile

Actual:

A bunch of:

out\java\src\main\java\org\openapitools\client\ApiClient.java:818: error: no suitable method found for create(byte[],MediaType)
            return RequestBody.create((byte[]) obj, MediaType.parse(contentType));
                              ^
    method RequestBody.create(MediaType,String) is not applicable
      (argument mismatch; byte[] cannot be converted to MediaType)
    method RequestBody.create(MediaType,ByteString) is not applicable
      (argument mismatch; byte[] cannot be converted to MediaType)
    method RequestBody.create(MediaType,byte[]) is not applicable
      (argument mismatch; byte[] cannot be converted to MediaType)
    method RequestBody.create(MediaType,File) is not applicable
      (argument mismatch; byte[] cannot be converted to MediaType)

Related issues/PRs

Suggest a fix

[toby-murray-snow-software]

In 5.0.1 the generated line in ApiClient was:

return RequestBody.create(MediaType.parse(contentType), (byte[]) obj);

in 5.1.0 it is:

return RequestBody.create((byte[]) obj, MediaType.parse(contentType));

Looks like this change was introduced in #8969

[wing328]

    VersionGetResponse:
      type: string
      description: The version of this service
      required:
        - status
      properties:
        status:
          type: string
          description: OK

Should it be type: object instead?

[wing328]

I did a test with the latest master and the output compiles without issues. Can you give it another try with the latest master?

[toby-murray-snow-software]

Should it be type: object instead?

I don't believe so - I'll look at the response, it's intended to be a simple string.

I did a test with the latest master and the output compiles without issues

You used the attached YAML and it compiles? On both this sample and the real YAML I distilled it from it continues to not compile for me with the latest Docker image (563bdd246a47).

docker run --rm -v "${PWD}:/local" openapitools/openapi-generator-cli generate -i /local/service.yaml -g java -o /local
<...snip generation output...>

> Task :compileJava FAILED
C:\Users\tobmur\git\myproject\src\main\yaml\out\java2\src\main\java\org\openapitools\client\ApiClient.java:818: error: no suitable method found for create(byte[],MediaType)
            return RequestBody.create((byte[]) obj, MediaType.parse(contentType));
                              ^
    method RequestBody.create(MediaType,String) is not applicable
      (argument mismatch; byte[] cannot be converted to MediaType)
    method RequestBody.create(MediaType,ByteString) is not applicable
      (argument mismatch; byte[] cannot be converted to MediaType)
    method RequestBody.create(MediaType,byte[]) is not applicable
      (argument mismatch; byte[] cannot be converted to MediaType)
    method RequestBody.create(MediaType,File) is not applicable
      (argument mismatch; byte[] cannot be converted to MediaType)
C:\Users\tobmur\git\myproject\src\main\yaml\out\java2\src\main\java\org\openapitools\client\ApiClient.java:821: error: no suitable method found for create(File,MediaType)
            return RequestBody.create((File) obj, MediaType.parse(contentType));
                              ^
    method RequestBody.create(MediaType,String) is not applicable
      (argument mismatch; File cannot be converted to MediaType)
    method RequestBody.create(MediaType,ByteString) is not applicable
      (argument mismatch; File cannot be converted to MediaType)
    method RequestBody.create(MediaType,byte[]) is not applicable
      (argument mismatch; File cannot be converted to MediaType)
    method RequestBody.create(MediaType,File) is not applicable
      (argument mismatch; File cannot be converted to MediaType)
C:\Users\tobmur\git\myproject\src\main\yaml\out\java2\src\main\java\org\openapitools\client\ApiClient.java:829: error: no suitable method found for create(String,MediaType)
            return RequestBody.create(content, MediaType.parse(contentType));
                              ^
    method RequestBody.create(MediaType,String) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
    method RequestBody.create(MediaType,ByteString) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
    method RequestBody.create(MediaType,byte[]) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
    method RequestBody.create(MediaType,File) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
C:\Users\tobmur\git\myproject\src\main\yaml\out\java2\src\main\java\org\openapitools\client\ApiClient.java:1079: error: no suitable method found for create(String,MediaType)
                reqBody = RequestBody.create("", MediaType.parse(contentType));
                                     ^
    method RequestBody.create(MediaType,String) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
    method RequestBody.create(MediaType,ByteString) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
    method RequestBody.create(MediaType,byte[]) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
    method RequestBody.create(MediaType,File) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
C:\Users\tobmur\git\myproject\src\main\yaml\out\java2\src\main\java\org\openapitools\client\ApiClient.java:1230: error: no suitable method found for create(File,MediaType)
                mpBuilder.addPart(partHeaders, RequestBody.create(file, mediaType));
                                                          ^
    method RequestBody.create(MediaType,String) is not applicable
      (argument mismatch; File cannot be converted to MediaType)
    method RequestBody.create(MediaType,ByteString) is not applicable
      (argument mismatch; File cannot be converted to MediaType)
    method RequestBody.create(MediaType,byte[]) is not applicable
      (argument mismatch; File cannot be converted to MediaType)
    method RequestBody.create(MediaType,File) is not applicable
      (argument mismatch; File cannot be converted to MediaType)
C:\Users\tobmur\git\myproject\src\main\yaml\out\java2\src\main\java\org\openapitools\client\ApiClient.java:1233: error: no suitable method found for create(String,<null>)
                mpBuilder.addPart(partHeaders, RequestBody.create(parameterToString(param.getValue()), null));
                                                          ^
    method RequestBody.create(MediaType,String) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
    method RequestBody.create(MediaType,ByteString) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
    method RequestBody.create(MediaType,byte[]) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
    method RequestBody.create(MediaType,File) is not applicable
      (argument mismatch; String cannot be converted to MediaType)
Note: Some messages have been simplified; recompile with -Xdiags:verbose to get full output
6 errors

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':compileJava'.
> Compilation failed; see the compiler error output for details.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/6.7.1/userguide/command_line_interface.html#sec:command_line_warnings

BUILD FAILED in 1s
1 actionable task: 1 executed

I'm on Windows with this, I wouldn't imagine this is a platform difference but maybe?

[cb-manideep]

@wing328 The okhttp3 version needs to be updated to 4.9.0
compile 'com.squareup.okhttp3:okhttp:4.9.0'

[wing328]

@cb-manideep can you please file a PR with the suggested change?

[cb-manideep]

@cb-manideep can you please file a PR with the suggested change?

Sure!

[toby-murray-snow-software]

@cb-manideep - any luck? If you're no longer intending to tackle this, I'd like to grab it in hopes of making it into the next release.

[cb-manideep]

@toby-murray-snow-software Please go ahead :)

[toby-murray-snow-software]

@wing328 - OkHTTP 3.13+ (including 4.*) needs Java 8. The current default of the generator is Java 7 and there's a flag to use Java 8. My understanding is 5.* intended to drop Java 7 and default to Java 8.

If it's viable to drop Java 7, I can submit a PR doing so. Without that, updating OkHTTP is marginally more complicated: needs to default to a ~2 year old version and only optionally use a modern version.

[Snorri1986]

The same problem on version 2.7.5 with Maven