public override ApplicationId GetAppId()
 {
     YarnServiceProtos.UseSharedCacheResourceRequestProtoOrBuilder p = viaProto ? proto
                          : builder;
     if (this.applicationId != null)
     {
         return(this.applicationId);
     }
     if (!p.HasApplicationId())
     {
         return(null);
     }
     this.applicationId = ConvertFromProtoFormat(p.GetApplicationId());
     return(this.applicationId);
 }