Sending file in Java doesn't work

[xhh]

I tried the uploadFile method in the Petstore's Java client:
https://github.com/wordnik/swagger-codegen/blob/master/samples/client/petstore/java/src/main/java/com/wordnik/petstore/api/PetApi.java#L173

but got the following error:

Caused by: com.wordnik.client.ApiException: {"code":400,"message":"org.jvnet.mimepull.MIMEParsingException: Missing start boundary"}
        at com.wordnik.client.ApiInvoker.invokeAPI(ApiInvoker.java:168)
        at com.wordnik.petstore.api.PetApi.uploadFile(PetApi.java:189)

It seems to due to the "boundary" is not set, as in similar discussions I found:
Image upload with Swagger UI in Java
swagger-api/swagger-ui#288

[xhh]

Related issues: #29 #227

[fehguy]

There has been some feature support missing in the codegen. I've added this for java in master