org.apache.spark.util.SerializableBuffer.scala Maven / Gradle / Ivy
/*
* 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,
* 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.apache.spark.util
import java.io.{EOFException, IOException, ObjectInputStream, ObjectOutputStream}
import java.nio.ByteBuffer
import java.nio.channels.Channels
/**
* A wrapper around a java.nio.ByteBuffer that is serializable through Java serialization, to make
* it easier to pass ByteBuffers in case class messages.
*/
private[spark]
class SerializableBuffer(@transient var buffer: ByteBuffer) extends Serializable {
def value: ByteBuffer = buffer
private def readObject(in: ObjectInputStream): Unit = Utils.tryOrIOException {
val length = in.readInt()
buffer = ByteBuffer.allocate(length)
var amountRead = 0
val channel = Channels.newChannel(in)
while (amountRead < length) {
val ret = channel.read(buffer)
if (ret == -1) {
throw new EOFException("End of file before fully reading buffer")
}
amountRead += ret
}
buffer.rewind() // Allow us to read it later
}
private def writeObject(out: ObjectOutputStream): Unit = Utils.tryOrIOException {
out.writeInt(buffer.limit())
if (Channels.newChannel(out).write(buffer) != buffer.limit()) {
throw new IOException("Could not fully write buffer to output stream")
}
buffer.rewind() // Allow us to write it again later
}
}