ChannelStringWriter.scala

import org.jboss.netty.channel.{ChannelFuture, Channel}
import org.jboss.netty.buffer.ChannelBuffers
import org.jboss.netty.util.CharsetUtil
import java.nio.charset.Charset

/**
 * @author Matt Hicks <mhicks@outr.com>
 */
class ChannelStringWriter(channel: Channel, buffer: Int = 512, charset: Charset = CharsetUtil.UTF_8) {
  private val b = new StringBuilder
  private var writeFuture: ChannelFuture = null

  def write(s: String) = {
    b.append(s)
    if (b.length >= buffer) {
      flush()
    }
  }

  def flush() = {
    if (b.length > 0) {
      writeFuture = channel.write(ChannelBuffers.wrappedBuffer(b.toString().getBytes(charset)))
      b.clear()
    }
  }

  def finish() = {
    flush()
    writeFuture
  }
}