This could use some formatting and naming cleanup - the indentation is weird. Also, it might be better to inline `isAnnotationExistClassLevel` rather than having its own function.

What about this?
```
def isDeveloperApi(className: String) = {
  try {
    val clazz = mirror.classSymbol(Class.forName(className, false, classLoader))
    clazz.annotations.exists(_.tpe =:= unv.typeOf[org.apache.spark.annotation.DeveloperApi])
  } catch {
    case _: Throwable => {
      println("Error determining Annotations: " + className)
      false
     }
   }
 }
```