Example #1
0
  private static boolean changeClassTypeArgument(
      PsiMethod myMethod,
      Project project,
      PsiType superReturnType,
      PsiClass superClass,
      Editor editor,
      PsiType returnType) {
    if (superClass == null || !superClass.hasTypeParameters()) return true;
    final PsiClass superReturnTypeClass = PsiUtil.resolveClassInType(superReturnType);
    if (superReturnTypeClass == null
        || !(superReturnTypeClass instanceof PsiTypeParameter
            || superReturnTypeClass.hasTypeParameters())) return true;

    final PsiClass derivedClass = myMethod.getContainingClass();
    if (derivedClass == null) return true;

    final PsiReferenceParameterList referenceParameterList =
        findTypeArgumentsList(superClass, derivedClass);
    if (referenceParameterList == null) return true;

    final PsiElement resolve =
        ((PsiJavaCodeReferenceElement) referenceParameterList.getParent()).resolve();
    if (!(resolve instanceof PsiClass)) return true;
    final PsiClass baseClass = (PsiClass) resolve;

    if (returnType instanceof PsiPrimitiveType) {
      returnType = ((PsiPrimitiveType) returnType).getBoxedType(derivedClass);
    }

    final PsiSubstitutor superClassSubstitutor =
        TypeConversionUtil.getSuperClassSubstitutor(superClass, baseClass, PsiSubstitutor.EMPTY);
    final PsiType superReturnTypeInBaseClassType =
        superClassSubstitutor.substitute(superReturnType);
    final PsiResolveHelper resolveHelper = JavaPsiFacade.getInstance(project).getResolveHelper();
    final PsiSubstitutor psiSubstitutor =
        resolveHelper.inferTypeArguments(
            PsiTypesUtil.filterUnusedTypeParameters(
                superReturnTypeInBaseClassType, baseClass.getTypeParameters()),
            new PsiType[] {superReturnTypeInBaseClassType},
            new PsiType[] {returnType},
            PsiUtil.getLanguageLevel(superClass));

    final TypeMigrationRules rules = new TypeMigrationRules();
    final PsiSubstitutor compoundSubstitutor =
        TypeConversionUtil.getSuperClassSubstitutor(superClass, derivedClass, PsiSubstitutor.EMPTY)
            .putAll(psiSubstitutor);
    rules.setBoundScope(new LocalSearchScope(derivedClass));
    TypeMigrationProcessor.runHighlightingTypeMigration(
        project,
        editor,
        rules,
        referenceParameterList,
        JavaPsiFacade.getElementFactory(project).createType(baseClass, compoundSubstitutor));

    return false;
  }