java8 / java8-localdatetime options are ignored

Description

Hi. I'm using the command line codegen to generate a Java model using the Java 8 options for dates/times, but I can see that the generated Java classes have references to Joda instead, like this:

@SerializedName("timeOfDayFrom")
private org.joda.time.* timeOfDayFrom = null;

I've also noticed this in the output:

[main] INFO io.swagger.codegen.DefaultGenerator - Model LocalTime not imported due to import mapping

Swagger-codegen version

I'm using the current master branch, which is 2.4.0-SNAPSHOT.

Swagger declaration file content or url

I'm using a JSON declaration generated by camel-rest-swagger. The relevant part is this one:

...

"timeOfDayFrom" : {
  "description" : "Minimum time of day (inclusive) to include in search results. Null means no minimum. ISO 8601 format, e.g.: 12:34:56",
  "$ref" : "#/definitions/LocalTime"
},

...

"LocalTime" : {
  "type" : "object",
  "properties" : {
    "hour" : {
      "type" : "integer",
      "format" : "int32"
    },
    "minute" : {
      "type" : "integer",
      "format" : "int32"
    },
    "second" : {
      "type" : "integer",
      "format" : "int32"
    },
    "nano" : {
      "type" : "integer",
      "format" : "int32"
    }
  }
},

The original model is also Java, and the variable looks like this:

@ApiModelProperty("Minimum time of day (inclusive) to include in search results. Null means no minimum. ISO 8601 format, e.g.: 12:34:56")
private LocalTime timeOfDayFrom;

Command line used for generation

java -jar modules/swagger-codegen-cli/target/swagger-codegen-cli.jar generate -i http://10.17.1.65:8102/api/doc -l java -o /tmp/java-client -DdateLibrary=java8

Related issues/PRs

This issue seems to be related, but it's closed already:
https://github.com/swagger-api/swagger-codegen/issues/7177

Suggest a fix/enhancement

I've found out that if I remove these lines from DefaultCodegen.java

importMapping.put("DateTime", "org.joda.time.*");
importMapping.put("LocalDateTime", "org.joda.time.*");
importMapping.put("LocalDate", "org.joda.time.*");
importMapping.put("LocalTime", "org.joda.time.*");

Then the Java model is created correctly:

@SerializedName("timeOfDayFrom")
private LocalTime timeOfDayFrom = null;

Is it really a bug, or am I doing something wrong? Thank you very much.

Start in DefaultCodegen.java, focusing on the import mappings for DateTime, LocalDateTime, LocalDate, and LocalTime when the Java generator receives dateLibrary=java8. Reproduce the issue with the command and Swagger declaration in the report, then inspect the generated model and import output. Done means the Java 8 option no longer produces Joda references for the LocalTime definition.