How To Create An Empty File In Java I/O

Following the Java I/O code example how to create an empty file. We use File.createNewFile method to create a file. This method return a boolean value. Return true if the file is successfully created, and return false if the file already exists.

Source Code

File Name : CreateEmptyFileDemo.java

import java.io.File;
import java.io.IOException;

public class CreateEmptyFileDemo {
 public static void main(String[] args) {
  try {

   File file = new File("c:\\test.txt");

   if (file.createNewFile()) {
    System.out.println("File " +file.getName()+ " is successfully created!");
   } else {
    System.out.println("File " +file.getName()+ " already exists.");
   }

  } catch (IOException e) {
   e.printStackTrace();
  }
 }
}

Output

File test.txt is successfully created!

How To Get Mac Address Using Java Network

Following the Java Network example code to display a mac address in hexadecimal format.

Source Code

File Name : GetMacAddressDemo.java

import java.net.InetAddress;
import java.net.NetworkInterface;

public class GetMacAddressDemo {

 public static void main(String[] args) throws Exception {
     InetAddress inetAddress = InetAddress.getLocalHost();
     System.out.println("IP address : " + inetAddress.getHostAddress());

     NetworkInterface networkInteface = NetworkInterface.getByInetAddress(inetAddress);
     byte[] mac = networkInteface.getHardwareAddress();
     System.out.print("MAC address : ");

     StringBuilder sb = new StringBuilder();
     for (int i = 0; i < mac.length; i++) {
       sb.append(String
           .format("%02X%s", mac[i], (i < mac.length - 1) ? "-" : ""));
     }
     System.out.println(sb.toString());
   }
}

Output

IP address : 192.168.1.101
MAC address : 68-5D-43-93-07-3D

How To Get Total Space And Free Space Using Java I/O

Following the Java I/O code example to get total space and free space on a drive:

Source Code

File Name: TotalSpaceAndFreeSpaceDemo.java

import java.io.File;

public class TotalSpaceAndFreeSpaceDemo {
 public static void main(String[] args){
  File file = new File("D:");
     long totalSpace = file.getTotalSpace();
     System.out.println("Total space on drive " + file + " = " + totalSpace + "bytes");

     // Check the free space in C:
     long freeSpace = file.getFreeSpace();
     System.out.println("Free space on drive " + file + " = " + freeSpace + "bytes");
 }
}

Output

Total space on drive D: = 299266732032bytes
Free space on drive D: = 38464524288bytes