genServerNames.scala

/**
 * hosts(i) corresponds to serversKey(i) and serversVal(i)
 * 
 * hosts are "hostname:port" (same as cluster nodeId).  
 * Note: port is the server's client port.  port+1 and port+2 are used for serversVal.
 * 
 * serversKey are "server.1" (see Zookeeper Admin Guide)
 * serversVal are "hostname:nnnn:nnnn"
 */
case class ServerNames(hosts: IndexedSeq[String], 
  serversKey: IndexedSeq[String], serversVal: IndexedSeq[String]) {
    
  def useReplicated = hosts.size > 1
}

def genServerNames(hosts: String): ServerNames = {
  val hostsArr = hosts.split(",")
  val serversKeyArr = new Array[String](hostsArr.length)
  val serversValArr = new Array[String](hostsArr.length)
  for ((server, idx) <- hostsArr.zipWithIndex) {
    val (host, port) = if (server.contains(":")) {
      val parts = server.split(":")
      (parts(0), parts(1).toInt)
    } else {
      (server, clientPort)
    }
    hostsArr(idx) = host + ":" + port
    serversKeyArr(idx) = "server." + (idx+1)
    serversValArr(idx) = host + ":" + (port+1) + ":" + (port+2)
  }
  ServerNames(hostsArr.toIndexedSeq, 
    serversKeyArr.toIndexedSeq, serversValArr.toIndexedSeq)
}