How to Read Excel data with Apache POI

//Section 1: Import Section
import java.io.File;
import java.io.FileInputStream;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;


//Section 2 : Declare a class
  
public class readingXL {

    
//Section 3:This method will read data from excel
public void readXL() throws Exception{
        String sPath = "D:\\Selenium_Projects\\abc.xls"; //This is excel file path
        File myFile = new File(sPath);  //Pass this file path to myFile
        FileInputStream myStream = new FileInputStream(myFile);  //Declare a input stream and pass myFile in it
       
        HSSFWorkbook myWB = new HSSFWorkbook(myStream); //Declare work book and pass myStream in it
        HSSFSheet mySheet = myWB.getSheetAt(0); //Go to the sheet at index 0 i.e. First One
       
        int xRows = mySheet.getLastRowNum() + 1; //Get rows number
        int xCols = mySheet.getRow(0).getLastCellNum(); //Get column number
       
        System.out.println("Number of rows are : " + xRows);
        System.out.println("Number of columns are : " + xCols);
       
        String[][] xData = new String[xRows][xCols]; //Declare an array of string type which will hold values
       
        for(int i=0; i<xRows; i++){
            HSSFRow row = mySheet.getRow(i); //Pointing to the row from we need to read data; it will be first row at first iteration
           
            for(int j=0; j<xCols; j++){
                HSSFCell cell = row.getCell(j);  //Pointing to the cell of the row
               
                String value = cellToString(cell); //Getting value of the cell and put it into a variable "value"; Here cellToString() is a user define function which will convert cell value in string.  
               
                xData[i][j] = value;   //Store that value in to array
               
                System.out.print(value); //Print data in console
                System.out.print("##");
            }
            System.out.println("@");
        }
    }
   
    
//Section 4: This method will convert object of type cell into String
public String cellToString(HSSFCell cell){//Declare a method "cellToString()" which will convert an object of type cell into string
        int type = cell.getCellType();// This method "getCellType()" will return an integer which is 0-5 and on the basis of this integer value we will use SWITCH
       
        Object result; // Its an temporary object which will hold value in switch statement
       
        switch(type){
       
        case HSSFCell.CELL_TYPE_NUMERIC: // If a cell contain numeric value then it will return 0
            result = cell.getNumericCellValue();
            System.out.println("Value of type is : " +type);
            break;
           
        case HSSFCell.CELL_TYPE_STRING: // If a cell string value then it will return 1
            result = cell.getStringCellValue();
            break;
           
        case HSSFCell.CELL_TYPE_FORMULA:  // If a cell contain formula then it will return 2
            System.out.println("Can not eveulate formila in JAVA");
            throw new RuntimeException("Can not eveulate formila in JAVA");
           
        case HSSFCell.CELL_TYPE_BLANK: // If a cell contain blank value then it will return 3
            result = "";
            break;
           
        case HSSFCell.CELL_TYPE_BOOLEAN: // If a cell contain boolean value then it will return 4
            result = cell.getBooleanCellValue();
            break;
           
        case HSSFCell.CELL_TYPE_ERROR:// If a cell contain error then it will return 5
            System.out.println("Can not eveulate formila in JAVA");
            throw new RuntimeException("This cell has an error");
           
        default:
            throw new RuntimeException("We dont support this cell type : " +type);
        }
        return result.toString();   //Here "toString()" method will convert result object to string; Here question may arise i.e why convert value into string...? This is so because we already have an array[xData] in which we will put this value and that is declared as STRING.
       
    }
}