javascript array support name index

<script type="text/javascript">  
  var arr = [];
   arr.push("J");
  arr["J"] = "Jani"; 
  arr.push("H");
  arr["H"] = "Hege" ; 
  arr.push("S");
  arr["S"] = "Stale"; 
  document.write(arr["S"] + "<br />")  
  document.write(arr.push("KaiJim") + "<br />")  
  arr["KaiJim"]="S";
  document.write(arr)  
</script>