import java.io.IOException;
import java.util.concurrent.TimeUnit;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
 

public class Login {

    /**
     * @param args
     * @throws IOException 
     */
    public static void main(String[] args) throws IOException {
        // TODO Auto-generated method stub
             for(int i=1; i<=4; i++){
                
                        WebDriver myDriver=new FirefoxDriver();
                myDriver.manage().timeouts().implicitlyWait(50, TimeUnit.SECONDS);
                myDriver.get("https://www.revenewonline.net/rolcelive_test/index.aspx");
             myDriver.findElement(By.name("user_name")).sendKeys(FuncLib.fn_GetCellData("Login", "UserName", i));
            myDriver.findElement(By.xpath("//input[@name='user_password']")).sendKeys(FuncLib.fn_GetCellData("Login", "UserName", i));
             myDriver.findElement(By.xpath("//input[@name='Login']")).click();
            myDriver.close();
            
            }
    }
}


##############################################################################################
 import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.math.BigDecimal;

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
 import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;


public class FuncLib {
  public static String TestDataPath=".xlsx";
        public static String fn_GetCellData(String SheetName, String ColumnName, int Rownumber) throws IOException{
          
                File xlFile=new File(TestDataPath);
                FileInputStream fis=new FileInputStream(xlFile);       
            XSSFWorkbook workbook_Object=new XSSFWorkbook(fis);
            int columnNum=0;
            Sheet sheetobj=workbook_Object.getSheet(SheetName);
            for(int i=0; i<=sheetobj.getRow(0).getLastCellNum(); i++){
             String ColName=sheetobj.getRow(0).getCell(i).getStringCellValue();
               if(ColumnName.equalsIgnoreCase(ColName)){
                   columnNum=i;
                   break;
               }
             }
            Row Required_ROw_Object=sheetobj.getRow(Rownumber);                                               
            Cell Required_CellObject= Required_ROw_Object.getCell(columnNum, Required_ROw_Object.CREATE_NULL_AS_BLANK);
               String TestData="";                             
                
              int cellType=Required_CellObject.getCellType();  
              
              if(cellType==XSSFCell.CELL_TYPE_NUMERIC){                                                                   
                  BigDecimal myVal=BigDecimal.valueOf(Required_CellObject.getNumericCellValue());
                  TestData=myVal.toPlainString();                    
              }else if(cellType==XSSFCell.CELL_TYPE_BLANK){                                                               
                  TestData=""   ;            
             }else if(cellType==XSSFCell.CELL_TYPE_STRING){                                                             
                 TestData=Required_CellObject.getStringCellValue();                                                                                                                           
             }           
              fis.close();
           return TestData;
       }
}