How to remove duplicate from array or convert string into array and remove duplicate records

var getEmail="abc@gmail.com,xyz@gmail.com,abc@gmail.com,abc@gmail.com,helpdesk@workingcode.in";
//convert string into array
var arr=[];
var getEmailSplit=getEmail.split(",");
for(var i=0;i<getEmailSplit.length;i++)
{
arr.push(getEmailSplit[i])
}
gs.print(arr)
 var au = new ArrayUtil();
  gs.print(au.unique(arr));