Hacktoberfest 2026: the issues maintainers tagged for October, open and beginner-friendly. Browse Hacktoberfest issues

Allow DataObject properties to be ignored by generated converter

Open
  • Is something wrong?
#213 1 comment 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Feature
Clarity
Mostly clear
Activity status
Stale
Tech stack
java, kotlin
Domain
tooling

Research direction

Start by locating the converter-generation path for @DataObject and how it processes properties, then compare the existing @JvmField behavior with the proposed @GenIgnore or @ConverterIgnore approach. The work is done when a language-independent annotation can exclude a DataObject property from generated conversion and the EnumSet example no longer causes generation to fail.

Written by the indexing model from the issue text.

Description

In certain circumstances it is desirable or necessary to omit a property from the generated converter.

For example, the following Kotlin DataObject will not compile successfully:

@DataObject(generateConverter = true)
class EnumSetDataObject() {
    var enumSet: Set<MyEnum> = emptySet()
    ...
}

error: Could not generate element for io.vertx.example.EnumSetDataObject: 
Illegal type ? extends io.vertx.example.MyEnum of kind WILDCARD

The desired effect (omitting enumSet from the converter) can be accomplished in Kotlin by using the @JvmField annotation, however, that is a language-specific solution.

I think that it would be useful to provide this functionality, either via the @GenIgnore annotation or a new @ConverterIgnore annotation.

Dominant language
Java
Stars
111
Forks
88
No merged PRs in 30d

Getting set up

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

More from eclipse-vertx/vertx-codegen

All issues in eclipse-vertx/vertx-codegen

Similar issues

More Java issues

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.