Checking an empty or null string(Request)

[@kriti]

if (!("".equals(req_.getNonEmpData())) ||!(req_.getNonEmpData().equals(null)) )
{
itemsNonEmp= req_.getNonEmpData().split(",");
}
if ((req_.getEmpData() != null) && (!req_.getEmpData().equals("")))
{
itemsEmp=req_.getEmpData().split(",");
}

I have checked with every possible scenario for checking null or empty.

But even if the value of req_.getNonEmpData()=null,its entering the block and trying to split the empty variable..Hence Null pointer exception is being thrown...At the time of debugging,I have hardcoded the value of req_.getNonEmpData() to null,then also its entering in the block.

Any suggestion ,How to check for empty or null value in req_.getNonEmpData()