string that is serialized by php convert to Map[Any, Any]

PhpSerializer.scala

class PhpSerializer {             
  val patternString = """s:(\d+):\"([^;]*)\";?""".r 
  val patternInt    = """i:(\d+);?""".r
  val patternDouble = """d:(-)?(\d+)(\.\d+)?;?""".r;
  val patternArray  = """a:(\d+):\{(.*)\};?""".r;

  def parseArray(len: Int, attr: String): Any = {
    val childs = attr.split(";").toList 
    val len1 = childs.length   
    if (len1 > 1) {            
      var ab = new scala.collection.mutable.ArrayBuffer[Any]
      var i = 0                
      val childsLength = childs.length
      while(i < childsLength) {
        if (childs(i).startsWith("a:")) {
          val end = childs.indexOf("}") + 1
          val a = Range(i, end).map(childs(_)).mkString(";")
          ab += de(a)
          i = end
        } else {
          ab += de(childs(i))
          i+= 1
        }
      }
      val abLength = ab.length
      Range(0, abLength,2).map( ab(_) ).toList.zip(
              Range(1, abLength,2).map( ab(_) ).toList 
            ).toMap[Any, Any]
    } else {
      Nil
    }
  }
  
  def de(ss: String): Any = ss match {
      case "N;" => null
      case patternString(len, str) => str
      case patternInt(i) => i
      case patternDouble(sign, d1, d2) => sign match {
          case "-" => (sign + d1 + d2).toDouble
          case _   => (d1 + d2).toDouble  
        }
      case patternArray(len, attr) => parseArray(len.toInt, attr)
      case "O" => null // not implemented
      case _ => println("unmatch"); ss
  }
}

SerializeTest.scala

object SerializeTest {
  def main(args: Array[String]) {
    val ser = new Serializer
    List(
      "i:10;"
      ,"d:1.5;"
      ,"d:42.195;"
      ,"s:1:\"1\";"
      ,"s:2:\"10\";"
      ,"s:3:\"1s1\";"
      ,"s:3:\"へろーわーるど\";"
      ,"N;"
      ,"a:0:{};"
      ,"a:3:{i:0;i:1;i:1;i:2;i:2;i:3;};"
      ,"a:3:{i:0;i:1;i:1;i:2;i:2;i:3;}"
      ,"a:3:{s:1:\"a\";i:1;s:1:\"b\";i:2;s:1:\"c\";i:3;};"
      ,"a:3:{i:0;i:12;i:1;i:13;i:2;i:14;}"
      ,"a:3:{s:9:\"free_word\";s:18:\"ふりーわーど\";s:6:\"madori\";a:3:{i:0;i:12;i:1;i:13;i:2;i:14;};s:12:\"walkminutesh\";i:7;};"
    ).foreach { (s: String) =>
      println("======================")
      println(s)
      println(ser.de(s))
    }
}