I am working with Java 21 & Springboot 3.3 and I create controller using open-api-generator gradle plugin.
The controller generated is

  default ResponseEntity<CardinalityDTO> getService(
         @Valid @RequestParam(value = "param", required = false) List<String> param
    )

The param could contains comma and to avoid to split with comma, I have a initBinder like

  @InitBinder(value = "param")
  public void initBinder(PropertyEditorRegistry binder) {
    binder.registerCustomEditor(String[].class, new StringArrayPropertyEditor(null));
  }

The problem is initbinder works with String[] param, I have try a binder like

    binder.registerCustomEditor(List.class, new StringArrayPropertyEditor(null));

But it’s doesn’t work because it merge all param and I get ?param=value,value2&param=value3,value4 I get param=value,value2,value3,value3

So, I would like to generate String[] instead of List for param or a working solution to manage correctly comma with List