org.apache.spark.util.ByteBufferOutputStream.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.ByteArrayOutputStream
import java.nio.ByteBuffer
/**
* Provide a zero-copy way to convert data in ByteArrayOutputStream to ByteBuffer
*/
private[spark] class ByteBufferOutputStream(capacity: Int) extends ByteArrayOutputStream(capacity) {
def this() = this(32)
def getCount(): Int = count
private[this] var closed: Boolean = false
override def write(b: Int): Unit = {
require(!closed, "cannot write to a closed ByteBufferOutputStream")
super.write(b)
}
override def write(b: Array[Byte], off: Int, len: Int): Unit = {
require(!closed, "cannot write to a closed ByteBufferOutputStream")
super.write(b, off, len)
}
override def reset(): Unit = {
require(!closed, "cannot reset a closed ByteBufferOutputStream")
super.reset()
}
override def close(): Unit = {
if (!closed) {
super.close()
closed = true
}
}
def toByteBuffer: ByteBuffer = {
require(closed, "can only call toByteBuffer() after ByteBufferOutputStream has been closed")
ByteBuffer.wrap(buf, 0, count)
}
}