org.apache.spark.broadcast.Broadcast.scala Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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,
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* See the License for the specific language governing permissions and
* limitations under the License.
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package org.apache.spark.broadcast
import java.io._
import java.util.concurrent.atomic.AtomicLong
import org.apache.spark._
abstract class Broadcast[T](private[spark] val id: Long) extends Serializable {
def value: T
// We cannot have an abstract readObject here due to some weird issues with
// readObject having to be 'private' in sub-classes.
override def toString = "Broadcast(" + id + ")"
}
private[spark]
class BroadcastManager(val _isDriver: Boolean) extends Logging with Serializable {
private var initialized = false
private var broadcastFactory: BroadcastFactory = null
initialize()
// Called by SparkContext or Executor before using Broadcast
private def initialize() {
synchronized {
if (!initialized) {
val broadcastFactoryClass = System.getProperty(
"spark.broadcast.factory", "org.apache.spark.broadcast.HttpBroadcastFactory")
broadcastFactory =
Class.forName(broadcastFactoryClass).newInstance.asInstanceOf[BroadcastFactory]
// Initialize appropriate BroadcastFactory and BroadcastObject
broadcastFactory.initialize(isDriver)
initialized = true
}
}
}
def stop() {
broadcastFactory.stop()
}
private val nextBroadcastId = new AtomicLong(0)
def newBroadcast[T](value_ : T, isLocal: Boolean) =
broadcastFactory.newBroadcast[T](value_, isLocal, nextBroadcastId.getAndIncrement())
def isDriver = _isDriver
}