@Override
  public @NotNull IntentionPreviewInfo generatePreview(@NotNull Project project, @NotNull Editor editor, @NotNull PsiFile file) {
    String superClassName = StringUtil.getShortName(mySuperClassName);
    return new IntentionPreviewInfo.CustomDiff(JavaFileType.INSTANCE, "",
                                               "public class " + StringUtil.getShortName(myImplementationClassName) + " " +
                                               (myInterface ? PsiKeyword.IMPLEMENTS : PsiKeyword.EXTENDS) + " " + superClassName + " {\n" +
                                               "  public static " + superClassName + " provider() { return null;}" +
                                               "\n}");
  }
@Override
  public @NotNull IntentionPreviewInfo generatePreview(@NotNull Project project, @NotNull Editor editor, @NotNull PsiFile file)