org.opencypher.spark.impl.util.Annotation.scala Maven / Gradle / Ivy
/*
* Copyright (c) 2016-2018 "Neo4j, Inc." [https://neo4j.com]
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.opencypher.spark.impl.util
import org.opencypher.spark.api.io.{Labels, Node, Relationship, RelationshipType}
import scala.annotation.StaticAnnotation
import scala.reflect.runtime.universe._
import scala.tools.reflect.ToolBox
private[spark] object Annotation {
def labels[E <: Node: TypeTag]: Set[String] = synchronized {
get[Labels, E] match {
case Some(ls) => ls.labels.toSet
case None => Set(runtimeClass[E].getSimpleName)
}
}
def relType[E <: Relationship: TypeTag]: String = synchronized {
get[RelationshipType, E] match {
case Some(RelationshipType(tpe)) => tpe
case None => runtimeClass[E].getSimpleName.toUpperCase
}
}
def get[A <: StaticAnnotation: TypeTag, E: TypeTag]: Option[A] = synchronized {
val maybeAnnotation = staticClass[E].annotations.find(_.tree.tpe =:= typeOf[A])
maybeAnnotation.map { annotation =>
val tb = typeTag[E].mirror.mkToolBox()
val instance = tb.eval(tb.untypecheck(annotation.tree)).asInstanceOf[A]
instance
}
}
private def runtimeClass[E: TypeTag]: Class[E] = synchronized {
val tag = typeTag[E]
val mirror = tag.mirror
val runtimeClass = mirror.runtimeClass(tag.tpe.typeSymbol.asClass)
runtimeClass.asInstanceOf[Class[E]]
}
private def staticClass[E: TypeTag]: ClassSymbol = synchronized {
val mirror = typeTag[E].mirror
mirror.staticClass(runtimeClass[E].getCanonicalName)
}
}