Java Code Gen withXML option creates Models with mixed cases for fields

Description

The Codegen plugin generates the Model classes and adds the @XmlElement tag for the fields but the problem is it creates mixed cases based on object type. If the Swagger field type is String, it creates it with @XmlElement(name = "MixedCase") just like the field name in the Swagger. But for the field type of object, it creates the all small case @XmlElement(name = "smallcase").

It should create the @XmlElement just like its mentioned in Swagger file and should not make it all small case.

For the sample Swagger I posed, it created @XmlElement(name = "flight") as the type is Object.
But for String field CarrierCode, it created @XmlElement(name = "CarrierCode") just like it is in Swagger.

In the end, the Rest API call is failing as the the request is with mixed cases and not per Swagger.

Swagger-codegen version

io.swagger.codegen.v3
swagger-codegen-maven-plugin
3.0.25

Swagger declaration file content or url

"Flight": {
"type": "object",
"properties": {
"carrierCode": {
"type": "string",
"xml": {
"name": "CarrierCode",
"attribute": false,
"wrapped": false
},
"allowEmptyValue": false
},
"noseNumber": {
"type": "string",
"xml": {
"name": "NoseNumber",
"attribute": false,
"wrapped": false
},
"allowEmptyValue": false
}
},
"title": "Flight",
"xml": {
"name": "Flight",
"attribute": false,
"wrapped": false
}
}

Command line used for generation

language-java
withXml-true

Steps to reproduce

Run the Maven Code-Gen plugin for java withXML enabled for a swagger with both Object and String field types.

Related issues/PRs

Suggest a fix/enhancement

Plugin should create the @XmlElement case just like its mentioned in Swagger file and should not make it all small case.

For the sample Swagger I posed, it should create @xmlelement(name = "Flight") just like the Swagger definition.

Start by reproducing the Java generation path with the Maven Codegen plugin, language-java, and withXml=true using the supplied Swagger schema containing String and Object fields. Inspect the generated model annotations and compare the @XmlElement names with the Swagger XML names; done means both field types preserve the declared casing.