JetBrains/intellij-community · warning · ConfigurationException

''{0}'' is invalid qualified parameter class name

Error message

''{0}'' is invalid qualified parameter class name

What it means

Thrown by IntroduceParameterObjectDialog.canRun() (IntroduceParameterObjectDialog.java:503) in the 'Use existing class' branch when the existing-class field is empty or is not a syntactically valid qualified name (PsiNameHelper.isQualifiedName). Before the dialog even resolves the class, it checks the grammar of 'package.Outer.Inner' style names. A syntactically valid but unresolvable name is reported separately (error 246).

Source

Thrown at java/java-impl-refactorings/src/com/intellij/refactoring/introduceparameterobject/IntroduceParameterObjectDialog.java:503

      }
    }
    else if (!useExistingClass()) {
      final String className = getClassName();
      if (className.isEmpty() || !nameHelper.isIdentifier(className)) {
        throw new ConfigurationException(
          JavaRefactoringBundle.message("introduce.parameter.object.error.invalid.parameter.class.name", className));
      }
      final String packageName = getPackageName();

      if (packageName.isEmpty() || !nameHelper.isQualifiedName(packageName)) {
        throw new ConfigurationException(
          JavaRefactoringBundle.message("introduce.parameter.object.error.invalid.parameter.class.package.name", packageName));
      }
    }
    else {
      final String className = getExistingClassName();
      if (className.isEmpty() || !nameHelper.isQualifiedName(className)) {
        throw new ConfigurationException(
          JavaRefactoringBundle.message("introduce.parameter.object.error.invalid.qualified.parameter.class.name", className));
      }
      if (JavaPsiFacade.getInstance(getProject()).findClass(className, GlobalSearchScope.allScope(getProject())) == null) {
        throw new ConfigurationException(JavaRefactoringBundle.message("introduce.parameter.object.error.class.does.not.exist", className));
      }
    }
  }

  private @NotNull String getInnerClassName() {
    return myInnerClassNameTextField.getText().trim();
  }

  public @NotNull String getPackageName() {
    return packageTextField.getText().trim();
  }

  public @NotNull String getExistingClassName() {
    return existingClassField.getText().trim();

View on GitHub (pinned to be881553f2)

Solutions

1. Enter the fully qualified name ('com.acme.params.RequestParams') or use the class browser (...) to insert it.
2. If only the simple name is known, switch back to create-class mode or locate the package via Search Everywhere first.
3. Programmatically: check PsiNameHelper.getInstance(project).isQualifiedName(fqn) && !fqn.isEmpty() before opening/confirming the dialog.

Example fix

// before
// existing class field: RequestParams -> invalid qualified name

// after
// existing class field: com.acme.params.RequestParams

String fqn = getExistingClassName().trim();
PsiNameHelper helper = PsiNameHelper.getInstance(project);
if (fqn.isEmpty() || !helper.isQualifiedName(fqn)) {
  // block before OK; let user pick the class via a chooser instead of typing
}

When it happens

Trigger: Introduce Parameter Object with 'Use existing class' selected; the field left blank or holding 'Params', 'com..acme.Params', or 'com.acme.My Params' instead of a full dotted qualified name.

Common situations: Typing only the simple class name and forgetting the package, pasting with whitespace, doubled dots, or clearing the field after browsing.

Related errors

• replace.constructor.builder.error.invalid.builder.class.name
• replace.constructor.builder.error.invalid.builder.qualified.
• Invalid package name: {0}
• Nothing found to extract
• ''{0}'' is invalid extracted class name

AI-assisted analysis of JetBrains/intellij-community@be881553f2 (2026-08-14). Data as JSON: /api/errors/a09cc53fa82f3e51. Report an issue: GitHub.