SonarCloud remove candidate rule: java:S1172 Unused method parameters should be removed

[CDellaGiusta]

This poll closes Friday, April 18th 2025.

Candidate rule for removal: java:S1172
Number of issues with this rule in Uyuni: 70
Rule: Unused method parameters should be removed
Software qualities impacted: MAINTAINABILITY
Why is this an issue:

A typical code smell known as unused function parameters refers to parameters declared in a function but not used anywhere within the function's body.
While this might seem harmless at first glance, it can lead to confusion and potential errors in your code.
Disregarding the values passed to such parameters, the function's behavior will be the same, but the programmer's intention won't be clearly expressed anymore.
Therefore, removing function parameters that are not being utilized is considered best practice.

=== Exceptions

The rule will not raise issues for unused parameters:

• that are annotated with @javax.enterprise.event.Observes
• in overrides and implementation methods
• in interface default methods
• in non-private methods that only throw or that have empty bodies
• in annotated methods, unless the annotation is @SuppressWarning("unchecked") or @SuppressWarning("rawtypes"), in >which case the annotation will be ignored
• in overridable methods (non-final, or not member of a final class, non-static, non-private), if the parameter is documented with a proper javadoc.

Should it be removed?:
Although it could be a code smell, there are cases in which a particular method MUST be called with one or more arguments, even if they are not used in the code (e.g. API endpoints with a user parameter). Removing the arguments straight away could have side-effects in this case.
If this rule is NOT removed, each case should be carefully evaluated to understand why the argument was not used (if it is a real mistake or some refactoring leftover)

All rule issues in Uyuni: https://sonarcloud.io/project/issues?languages=java&issueStatuses=OPEN%2CCONFIRMED&id=uyuni-project_uyuni&rules=java%3AS1172

Examples in our code:

  private ActionForward handleDispatchAction(ActionMapping mapping, RequestContext context) {
      return mapping.findForward(RhnHelper.CONFIRM_FORWARD);
  }

  private HtmlTag addButtonTo(StringBuilder buf, String name, String label) {
      LocalizationService ls = LocalizationService.getInstance();
      HtmlTag btn = new HtmlTag("button");
      btn.setAttribute("class", "btn btn-default");
      btn.setAttribute("type", "submit");
      btn.setAttribute("name", name);
      btn.setAttribute("value", ls.getMessage(label));
      btn.addBody(ls.getMessage(label));
      return btn;
  }