Dataprovider and TestNG: Is there a way to access next row data to compare with current row?

Question

For example I have an row1, row2, row3 and I want to compare col1 data for each

@Test(dataProvider = "Login")
    public void someTest(String num) throws InterruptedException {

//how to access below nextRow(num)??
if (current row num.equals nextRow(num)){
 Then do something.....
}

}