[Java] Default values for string-type query parameters are generated with two sets of quotes

Created by: OmriHarary

Description

In annotations on parameters for generated api methods, default values for request query parameters are surrounded in two sets of double quotes. Completely prevents compilation.

Example of problem code, generated using information below:

@ApiOperation(value = "", nickname = "fooGet", notes = "", tags={  })
    @ApiResponses(value = { 
        @ApiResponse(code = 200, message = "successful operation") })
    @RequestMapping(value = "/foo",
        method = RequestMethod.GET)
    default ResponseEntity<Void> fooGet(@ApiParam(value = "", defaultValue = ""foobar"") @Valid @RequestParam(value = "bar", required = false, defaultValue=""foobar"") String bar) {
        return new ResponseEntity<>(HttpStatus.NOT_IMPLEMENTED);

    }

Example partial result from running mvn package on generated project:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.7.0:compile (default-compile) on project openapi-spring: Compilation failure: Compilation failure:
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[43,80] ')' expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[43,86] <identifier> expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[43,88] ';' expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[43,159] ')' expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[43,165] <identifier> expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[43,167] ';' expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[43,179] = expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[43,181] illegal start of type
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[43,182] <identifier> expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[44,16] = expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[44,19] ';' expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[44,35] <identifier> expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[44,36] illegal start of type
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[44,37] '(' expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[44,47] illegal start of type
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[44,63] = expected
[ERROR] /path/to/src/main/java/org/openapitools/api/FooApi.java:[48,1] class, interface, or enum expected

openapi-generator version

latest master

OpenAPI declaration file content or url

openapi: 3.0.0
info:
  title: Issue example
  version: 1.0.0
paths:
  /foo:
    get:
      parameters:
        - name: bar
          in: query
          required: false
          schema:
            type: string
            default: foobar
      responses:
        default:
          description: successful operation

Command line used for generation

java -jar openapi-generator-cli.jar generate -g spring -i openapi.yaml

Steps to reproduce

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