default for Primitive types instead of wrapper classes

Description

I would like to generate java code (retrofit2 library) with java primitive types instead of java wrapper classes.

Integer -> int
Boolean -> boolean
Float -> float

Swagger-codegen version

2.2.1

Swagger declaration file content or url

  ForbiddenResponse:
    properties:
      success:
        type: boolean
        default: false
      data:
        type: object
        properties:
          code:
            type: integer
            default: 0

Command line used for generation

java
  -jar ./modules/swagger-codegen-cli/target/swagger-codegen-cli.jar  
    generate 
      -i path/to/api 
      -l java 
      -c retrofit2.json 
      -o path/to/out
      --language-specific-primitives boolean,int,float 
      --type-mappings Integer=int,Boolean=boolean,Float=float

Generated code:

Default for boolean primitive is correctly handled with

public class ForbiddenResponse {
  @SerializedName("success")
  private boolean success = false;

Default for int primitive is not correctly handler (null instead of 0, set as default)

public class ForbiddenResponseData {
  @SerializedName("code")
  private int code = null;

Desired code:

public class ForbiddenResponse {
  @SerializedName("success")
  private boolean success = false;

public class ForbiddenResponseData {
  @SerializedName("code")
  private int code = 0;

Reproduce the issue with the supplied Swagger declaration, retrofit2 configuration, and generation command, then inspect the Java generation templates and primitive type-mapping logic. Compare the boolean and integer default handling; done means generated primitive integer fields use 0 instead of null while boolean defaults remain correct.