An output stream that throws an exception if more than the given bytes have been written to it.

LimitedOutputStream.scala

import java.io.{FilterOutputStream, IOException, OutputStream}

class LimitedOutputStream(out: OutputStream , maxBytes: Long) extends FilterOutputStream(out) {

  private var bytesWritten: Long = 0L

  @throws(classOf[IOException])
  override def write(b: Int) {
    ensureCapacity(1)
    super.write(b)
  }

  @throws(classOf[IOException])
  override def write(b: Array[Byte]) {
    ensureCapacity(b.length)
    super.write(b)
  }

  @throws(classOf[IOException])
  override def write(b: Array[Byte], off: Int, len: Int) {
    ensureCapacity(len)
    super.write(b, off, len)
  }

  @throws(classOf[IOException])
  private def ensureCapacity(len: Int) {
    val newBytesWritten = bytesWritten + len
    if (newBytesWritten > maxBytes)
      throw new IOException("File size exceeded: " + newBytesWritten + " > " + maxBytes)
    bytesWritten = newBytesWritten
  }
}