jsp 숫자 천단위 처리

<SCRIPT LANGUAGE="JavaScript">
// 숫자만 입력가능하게 만드는 함수
function fnOnlyNumber()
{
 if((event.keyCode<48) || (event.keyCode>57)) {
  if(event.keyCode != 46 && event.keyCode != 44) {
   event.keyCode = null;
  }
 }
}

// 3자리마다 , 찍는 함수
function number_format(id,num) {

 num = num.replace(/,/g, "");
 if(num > 100){
  var num_str = num.toString();
  var result = '';
  for(var i=0; i<num_str.length; i++) {
   var tmp = num_str.length-(i+1);
   if(i%3==0 && i!=0) result = ',' + result;
   result = num_str.charAt(tmp) + result;
  }
  if(id == "gubun1_1") {
  document.sfr_input.gubun1_1.value=result;
  }else if(id == "gubun1_2") {
  document.sfr_input.gubun1_2.value=result;
  }else if(id == "gubun1_3") {
   document.sfr_input.gubun1_3.value=result;
  }else if(id == "gubun1_4") {
   document.sfr_input.gubun1_4.value=result;
  }else if(id == "gubun2_1") {
   document.sfr_input.gubun2_1.value=result;
  }else if(id == "gubun2_2") {
   document.sfr_input.gubun2_2.value=result;
  }else if(id == "gubun2_3") {
   document.sfr_input.gubun2_3.value=result;
  }else if(id == "gubun3_1") {
   document.sfr_input.gubun3_1.value=result;
  }else if(id == "gubun3_2") {
   document.sfr_input.gubun3_2.value=result;
  }else if(id == "gubun3_3") {
   document.sfr_input.gubun3_3.value=result;
  }else if(id == "gubun3_4") {
   document.sfr_input.gubun3_4.value=result;
  }
 }
}

// 입력값이 NULL일때 경고창 띄우는 함수
function check_action(){
 <%
  if((gubun).equals(setYear)) 
  {
 %> 
  document.sfr_input.action = "SS_024_update_con.jsp?staff=<%=staff%>&&phoneNo=<%=phoneNo%>&&year=<%=setYear%>&&month=<%=setMonth%>&&pass_month=<%=monthSelect%>";
  number_format("gubun1_1",document.sfr_input.gubun1_1.value);
  number_format("gubun1_2",document.sfr_input.gubun1_2.value);
  number_format("gubun1_3",document.sfr_input.gubun1_3.value);
  number_format("gubun1_4",document.sfr_input.gubun1_4.value);
  number_format("gubun2_1",document.sfr_input.gubun2_1.value);
  number_format("gubun2_2",document.sfr_input.gubun2_2.value);
  number_format("gubun2_3",document.sfr_input.gubun2_3.value);
  number_format("gubun3_1",document.sfr_input.gubun3_1.value);
  number_format("gubun3_2",document.sfr_input.gubun3_2.value);
  number_format("gubun3_3",document.sfr_input.gubun3_3.value);
  number_format("gubun3_4",document.sfr_input.gubun3_4.value);
  number_format("gubun4_1",document.sfr_input.gubun4_1.value);
  number_format("gubun5_1",document.sfr_input.gubun5_1.value);
 <%
  }else{
 %>
  document.sfr_input.gubun1_1.value = '';
  document.sfr_input.gubun1_2.value = '';
  document.sfr_input.gubun1_3.value = '';
  document.sfr_input.gubun1_4.value = '';
  document.sfr_input.gubun2_1.value = '';
  document.sfr_input.gubun2_2.value = '';
  document.sfr_input.gubun2_3.value = '';
  document.sfr_input.gubun3_1.value = '';
  document.sfr_input.gubun3_2.value = '';
  document.sfr_input.gubun3_3.value = '';
  document.sfr_input.gubun3_4.value = '';
  document.sfr_input.gubun4_1.value = '';
  document.sfr_input.gubun5_1.value = '';
 <%
  }
  if(("u").equals(tempYear.substring(4,5)))
  {
 %>
  alert("정보가 수정되었습니다");
 <%
  }else if(("i").equals(tempYear.substring(4,5)))
  {
 %>
  alert("정보가 추가되었습니다");
 <%
  }
 %>
}

</SCRIPT>