How to read a file using java.util.Scanner class in Java through a simple program ?.

A simple Java program demonstrating how to read a file using java.util.Scanner class.

1. Create a text file say demo as customer.txt below -

a. customer.txt

-------Customer Details -------

First Name : Jonty
Last Name  : Magic
Email      : Jonty@Magicman

-------------------------------

2. Create a Java class to read customer.txt file -

package com.hubberspot.example;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;


public class ScannerExample {

 public static void main(String[] args) {

  try {
   // Creating a file with a name customer.txt
   // placed in the root folder of your Java 
   // project in eclipse
   // Storing the name of file as a String
   String fileName = "customer.txt";

   // Creating a File object by passing it a 
   // String containing the name of file
   File file = new File(fileName);

   // Creating a Scanner object using a constructor
   // which takes the file object. There are various 
   // constructors for Scanner class for different
   // purposes. We want to use Scanner class to read
   // data from a file on the system, So we are using 
   // a constructor which is taking an File object
   Scanner scanner = new Scanner(file);

   // Scanner class has many methods for scanning file
   // line-by-line. We use hasNextLine method which returns
   // true if there is yet another line to be read. putting the
   // condition in the while loop we traverse file line by line
   // and as soon as new line is figured out, we capture it by 
   // Scanner class's nextLine method and prints it on the console
   while(scanner.hasNextLine()) {
    String readLine = scanner.nextLine();
    System.out.println(readLine);
   }
  }
  catch (FileNotFoundException e) {

   e.printStackTrace();
  }

 }

}

Output of the program at the console :