Admin: 1 версия

2010-06-01T06:12:40Z

1 версия

в 18:01, 31 мая 2010

2010-05-31T18:01:43Z

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== 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>

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Admin: 1 версия

в 18:01, 31 мая 2010