Java/JDK 6/File

Create a file and change its attribute to readonly

   <source lang="java">

import java.io.File; import java.io.IOException; public class FileAttributesDemo {

 public static void main(String[] args) throws IOException {
   // Create a new file, by default canWrite=true, readonly=false
   File file = new File("test.txt");
   if (file.exists()) {
     file.delete();
   }
   file.createNewFile();
   System.out.println("Before. canWrite?" + file.canWrite());
   // set to read-only, atau canWrite = false */
   file.setWritable(false);
   System.out.println("After. canWrite?" + file.canWrite());
 }

}

       </source>
   
  
 
  

Creates a file and sets it to read-only.

   <source lang="java">

import java.io.File; import java.io.IOException; public class FileAttributesDemo {

   public static void main (String[] args) throws IOException {
       // Create a new file, by default canWrite=true,
      readonly=false
       File file = new File ("test.txt");
       if (file.exists ()) {
           file.delete ();
       }
       file.createNewFile ();
       System.out.println ("Before. canWrite?" + file.canWrite ());
       // set to read-only, atau canWrite = false */
       file.setWritable (false);
       System.out.println ("After. canWrite?" + file.canWrite ());
   }

}

       </source>
   
  
 
  

File Class Enhancements

   <source lang="java">

import java.io.File; public class DiskSpaceDemo {

 public static void main(String[] args) {
   File file = new File("C:");
   long totalSpace = file.getTotalSpace();
   System.out.println("Total space on " + file + " = " + totalSpace + "bytes");
   // Check the free space in C:
   long freeSpace = file.getFreeSpace();
   System.out.println("Free space on " + file + " = " + freeSpace + "bytes");
 }

} //Total space on C: = 40015953920bytes //Free space on C: = 6470483968bytes

       </source>
   
  
 
  

Get the free space

   <source lang="java">

import java.io.File; public class SpaceChecker {

 public static void main(String[] args) {
   File[] roots = File.listRoots();
   for (int i = 0; i < roots.length; i++) {
     System.out.println(roots[i]);
     System.out.println("Free space = " + roots[i].getFreeSpace());
     System.out.println();
   }
 }

}

       </source>
   
  
 
  

Get the total space

   <source lang="java">

import java.io.File; public class SpaceChecker {

 public static void main(String[] args) {
   File[] roots = File.listRoots();
   for (int i = 0; i < roots.length; i++) {
     System.out.println(roots[i]);
     System.out.println("Total space = " + roots[i].getTotalSpace());
     System.out.println();
   }
 }

}

       </source>
   
  
 
  

Get the usable space

   <source lang="java">

import java.io.File; public class SpaceChecker {

 public static void main(String[] args) {
   File[] roots = File.listRoots();
   for (int i = 0; i < roots.length; i++) {
     System.out.println(roots[i]);
     System.out.println("Usable space = " + roots[i].getUsableSpace());
     System.out.println();
   }
 }

}

       </source>
   
  
 
  

Getting a Proper URL from a File Object

   <source lang="java">

import java.io.*; import java.net.*; public class FileURL {

 public static void main(String args[]) throws MalformedURLException {
   File file = new File("The End");
   URL url2 = file.toURI().toURL();
   System.out.printf("Good url %s%n", url2);
 }

}

       </source>
   
  
 
  

List all roots

   <source lang="java">

import java.io.File; public class SpaceChecker {

 public static void main(String[] args) {
   File[] roots = File.listRoots();
   for (int i = 0; i < roots.length; i++) {
     System.out.println(roots[i]);
     System.out.println("Free space = " + roots[i].getFreeSpace());
     System.out.println("Usable space = " + roots[i].getUsableSpace());
     System.out.println("Total space = " + roots[i].getTotalSpace());
     System.out.println();
   }
 }

}

       </source>