fix(java): generate correct enum constructor when string format is uri

[hhomar]

Using the following spec:

openapi: 3.0.0
info:
  title: Sample API
  description: Optional multiline or single-line description in [CommonMark](http://commonmark.org/help/) or HTML.
  version: 0.1.9
servers:
  - url: http://api.example.com/v1
    description: Optional server description, e.g. Main (production) server
paths:
  /users:
    post:
      summary: Creates a user.
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                dataSchema:
                  type: string
                  format: uri
                  default: https://example.com/v1/schema.json
                  enum:
                    - https://example.com/v1/schema.json
                    - https://example.com/v2/schema.json

      responses: 
        '201':
          description: Created

The generated DataSchemaEnum is:

public enum DataSchemaEnum {
    COM_V1_SCHEMA_JSON("https://example.com/v1/schema.json"), 
    COM_V2_SCHEMA_JSON("https://example.com/v2/schema.json");
                                                                                      
    private URI value;                                                                
                                                                                      
    DataSchemaEnum(URI value) {
      this.value = value;
    }
}

private DataSchemaEnum dataSchema = URI.create("https://example.com/v1/schema.json");

Causing the following compilation errors:

[ERROR] incompatible types: java.lang.String cannot be converted to java.net.URI
[ERROR] incompatible types: java.net.URI cannot be converted to org.openapitools.client.model.UsersPostRequest.DataSchemaEnum

With the fix applied:

public enum DataSchemaEnum {
    COM_V1_SCHEMA_JSON(URI.create("https://example.com/v1/schema.json"),
    COM_V2_SCHEMA_JSON(URI.create("https://example.com/v2/schema.json");

    private URI value;                                                                
                                                                                      
    DataSchemaEnum(URI value) {
      this.value = value;
    }
}

private DataSchemaEnum dataSchema = DataSchemaEnum.COM_V1_SCHEMA_JSON;

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[wing328]

I did a test with the spec you provided but got the following errors:

[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR : 
[INFO] -------------------------------------------------------------
[ERROR] /private/tmp/enum/src/main/java/org/openapitools/client/model/UsersPostRequest.java:[91,18] error: no suitable method found for value(URI)
    method JsonWriter.value(String) is not applicable
      (argument mismatch; URI cannot be converted to String)
    method JsonWriter.value(boolean) is not applicable
      (argument mismatch; URI cannot be converted to boolean)
    method JsonWriter.value(Boolean) is not applicable
      (argument mismatch; URI cannot be converted to Boolean)
    method JsonWriter.value(float) is not applicable
      (argument mismatch; URI cannot be converted to float)
    method JsonWriter.value(double) is not applicable
      (argument mismatch; URI cannot be converted to double)
    method JsonWriter.value(long) is not applicable
      (argument mismatch; URI cannot be converted to long)
    method JsonWriter.value(Number) is not applicable
      (argument mismatch; URI cannot be converted to Number)
[ERROR] /private/tmp/enum/src/main/java/org/openapitools/client/model/UsersPostRequest.java:[96,31] error: cannot find symbol
  symbol:   method nextURI()
  location: variable jsonReader of type JsonReader
[INFO] 2 errors 

Did you get the same issue in your environment?

command: java -jar modules/openapi-generator-cli/target/openapi-generator-cli.jar generate -g java -i /tmp/a.yaml -o /tmp/enum/

[hhomar]

Hi

I was testing with:

java -jar modules/openapi-generator-cli/target/openapi-generator-cli.jar generate -g java --library resttemplate -i /tmp/a.yaml -o /tmp/enum

Sorry, I wasn't aware that the enum model was generated differently depending on the library. I guess this should have gone to the Java Spring team.

I've dug into it a bit and found the issue in the Java/modelEnum.mustache and Java/modelInnerEnum.mustache templates. I've updated the templates to check for isUri and now they generate the correct code:

public static class Adapter extends TypeAdapter<DataSchemaEnum> {
    @Override
    public void write(final JsonWriter jsonWriter, final DataSchemaEnum enumeration) throws IOException {
      jsonWriter.value(enumeration.getValue().toASCIIString());
    }

    @Override
    public DataSchemaEnum read(final JsonReader jsonReader) throws IOException {
      URI value = URI.create(jsonReader.nextString());
      return DataSchemaEnum.fromValue(value);
    }
  }

The modelEnum template update was a bit trickier as the isUri check was returning false. I had to add some additional code to the CodegenModel to check if the format is set as URI. I followed the same code as isUuid, but noticed a comment in DefaultCodeGen about UUID being a rare use case and may be removed in future DefaultCodegen.java#L3016, so I don't know if this change is the best approach.

There'ss also a native/modelEnum.mustache template, but it looks like the serialization library is fixed to Jackson JavaClientCodegen.java#L633, so the incorrect code can never be generated.

I've made all these changes on a separate branch (along with some tests). I'm not sure whether to pull those changes into this PR or raise as a separate PR?

[wing328]

confirmed this fix the issue in resttemplate

I've made all these changes on a separate branch (along with some tests). I'm not sure whether to pull those changes into this PR or raise as a separate PR?

yes please