Java by API/java.io/File

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File: canRead()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: canWrite()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: createNewFile()

   <source lang="java">
 

/*

*/

import java.io.File; public class MainClass {

 public static void main(String[] args) throws Exception{
   new File("newFile.txt").createNewFile();
 }

}


 </source>
   
  
 
  



File: createTempFile(String prefix, String suffix)

   <source lang="java">
 

import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.PrintStream; public class MainClass {

 public static void main(String[] args) {
   try {
     File tempFile = File.createTempFile("myfile", ".tmp");
     FileOutputStream fout = new FileOutputStream(tempFile);
     PrintStream out = new PrintStream(fout);
     out.println("some text");
   } catch (IOException ex) {
     System.out.println("There was a problem creating/writing to the temp file");
     ex.printStackTrace();
   }
 }

}


 </source>
   
  
 
  



File: delete()

   <source lang="java">
 

import java.io.File;

/*

*/

public class MainClass {

 public static void main(String[] args) {
   File bkup = new File("Delete.java~");
   bkup.delete();
 }

}


 </source>
   
  
 
  



File: deleteOnExit()

   <source lang="java">
 

import java.io.File; public class Main {

 public static void main(String[] a) {
   File file = new File("c:\\test\\test.txt");
   file.deleteOnExit();
 }

}


 </source>
   
  
 
  



File: exists()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: getAbsoluteFile()

   <source lang="java">
 

import java.io.File; public class Main {

 public static void main(String[] a) {
   File myFile = new File("C:" + File.separator + "jdk1.5.0" + File.separator, "File.java");
   System.out.println(myFile.getAbsoluteFile());
 }

}


 </source>
   
  
 
  



File: getAbsolutePath()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: getCanonicalPath()

   <source lang="java">
 

/*

* Output: 

getCanonicalPath() = C:\winnt

*/

import java.io.File; public class MainClass {

 public static void main(String args[]) {
   try {
     File file = new File("c:\\winnt");
     System.out.println("getCanonicalPath() = " + file.getCanonicalPath());
   } catch (Exception e) {
     e.printStackTrace();
   }
 }

}



 </source>
   
  
 
  



File: getFreeSpace()

   <source lang="java">
 

import java.io.File; public class Main {

 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");
 }

}


 </source>
   
  
 
  



File: getName()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: getParent()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: getParentFile()

   <source lang="java">
 

import java.io.File; public class Main {

 public static void main(String[] a) {
   File myFile = new File("C:" + File.separator + "jdk1.5.0" + File.separator, "File.java");
   System.out.println(myFile.getParentFile());
   System.out.println(myFile);
 }

}


 </source>
   
  
 
  



File: getPath()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: getTotalSpace()

   <source lang="java">
 

import java.io.File; public class Main {

 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");
 }

}


 </source>
   
  
 
  



File: getUsableSpace()

   <source lang="java">
 

import java.io.File; public class Main {

 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>
   
  
 
  



File: isAbsolute()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: isDirectory()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: isFile()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: isHidden()

   <source lang="java">
 

/*

* Output:

test.txt is not hidden

*/

import java.io.File; public class MainClass {

 public static void main(String[] args) {
   // Create an object that is a directory
   File myFile = new File("test.txt");
   System.out.println(myFile + (myFile.isHidden() ? " is" : " is not")
                      + " hidden");
 }

}


 </source>
   
  
 
  



File: lastModified()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: length()

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



File: list()

   <source lang="java">
 

/*

* Output:
* 

Directory of c:\

System.FormatException is a file

admin.lnk is a file admiss.lnk is a file AUTOEXEC.BAT is a file ... ...

*/

import java.io.File; public class MainClass {

 public static void main(String args[]) {
   String dirname = "c:\\";
   File f1 = new File(dirname);
   if (f1.isDirectory()) {
     System.out.println("Directory of " + dirname);
     String s[] = f1.list();
     for (int i = 0; i < s.length; i++) {
       File f = new File(dirname + "/" + s[i]);
       if (f.isDirectory()) {
         System.out.println(s[i] + " is a directory");
       } else {
         System.out.println(s[i] + " is a file");
       }
     }
   } else {
     System.out.println(dirname + " is not a directory");
   }
 }

}


 </source>
   
  
 
  



File: listFiles()

   <source lang="java">
 

import java.io.File; public class Main {

 public static void main(String[] a) {
   File myFile = new File("C:" + File.separator);
   for(File s: myFile.listFiles()){
     System.out.println(s);
   }
 }

}


 </source>
   
  
 
  



File: listFiles(FilenameFilter filter)

   <source lang="java">
 

/*

* Output:
The 0 matching items in the directory, , are:
*/

import java.io.File; import java.io.FilenameFilter; import java.util.Date; public class MainClass {

 public static void main(String[] args) {
   File myDir = new File("C:/");
   // Define a filter for java source files beginning with F
   FilenameFilter select = new FileListFilter("F", "java");
   File[] contents = myDir.listFiles(select);
   if (contents != null) {
     System.out.println("\nThe " + contents.length
         + " matching items in the directory, " + myDir.getName()
         + ", are:");
     for (File file : contents) {
       System.out.println(file + " is a "
               + (file.isDirectory() ? "directory" : "file")
               + " last modified on\n"
               + new Date(file.lastModified()));
     }
   } else {
     System.out.println(myDir.getName() + " is not a directory");
   }
   return;
 }

} class FileListFilter implements FilenameFilter {

 private String name; 
 private String extension; 
 public FileListFilter(String name, String extension) {
   this.name = name;
   this.extension = extension;
 }
 public boolean accept(File directory, String filename) {
   boolean fileOK = true;
   if (name != null) {
     fileOK &= filename.startsWith(name);
   }
   if (extension != null) {
     fileOK &= filename.endsWith("." + extension);
   }
   return fileOK;
 }

}


 </source>
   
  
 
  



File: listRoots()

   <source lang="java">
 

import java.io.File; import javax.swing.JFrame; public class MainClass extends JFrame {

 public static void main(String[] a) {
   File[] drives = File.listRoots();
   for (int i = 0; i < drives.length; i++)
     System.out.println(drives[i]);
 }

}


 </source>
   
  
 
  



File: mkdir()

   <source lang="java">
 

import java.io.File; /*

*/

public class MainClass {

 public static void main(String[] args) {
   System.out.println(new File("home").mkdir());
 }

}


 </source>
   
  
 
  



File: mkdirs() (Creates a directory including any parent directories)

   <source lang="java">
 

import java.io.File; public class Main {

 public static void main(String[] a) {
   File file = new File("c:\\test\\test\\");
   file.mkdirs();
 }

}


 </source>
   
  
 
  



File.pathSeparatorChar

   <source lang="java">
 

/*

* Output:

pathSeparatorChar = ;

*/

import java.io.File; public class MainClass {

 public static void main(String args[]) {
   try {
     System.out.println("pathSeparatorChar = " + File.pathSeparatorChar);
   } catch (Exception e) {
     e.printStackTrace();
   }
 }

}


 </source>
   
  
 
  



File: renameTo(File newFile)

   <source lang="java">
 

/*

* Output:
*  
*/

import java.io.File; public class MainClass {

 public static void main(String args[]) {
   try {
     File oldFile = new File(args[0]);
     File newFile = new File(args[1]);
     boolean result = oldFile.renameTo(newFile);
     System.out.println(result);
   } catch (Exception e) {
     e.printStackTrace();
   }
 }

}


 </source>
   
  
 
  



File.separator

   <source lang="java">
 

/*

* Output: 

 \
*/

import java.io.File; public class MainClass {

 public static void main(String args[]) {
   System.out.println(File.separator);
 }

}


 </source>
   
  
 
  



File: separatorChar

   <source lang="java">
 

import java.io.File; class FileDemo {

 public static void main(String args[]) throws Exception {
   // Display constants
   System.out.println("pathSeparatorChar = " + File.pathSeparatorChar);
   System.out.println("separatorChar = " + File.separatorChar);
 
 }

}


 </source>
   
  
 
  



File: setLastModified(long time)

   <source lang="java">


import java.io.File; import java.util.Date; public class Main {

 public static void main(String[] args) throws Exception {
   File fileToChange = new File("C:/myfile.txt");
   Date filetime = new Date(fileToChange.lastModified());
   System.out.println(filetime.toString());
   System.out.println(fileToChange.setLastModified(System.currentTimeMillis()));
   filetime = new Date(fileToChange.lastModified());
   System.out.println(filetime.toString());
 }

}

 </source>
   
  
 
  



File: setReadOnly()

   <source lang="java">
 

/*

*/

import java.io.File; public class MainClass {

 public static void main(String[] args) throws Exception {
   File f = new File("f");
   if (!f.setReadOnly()) {
     System.out.println("Grrr! Can"t set file read-only.");
     return;
   }
 }

}


 </source>
   
  
 
  



File: setWritable(boolean writable)

   <source lang="java">
 

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

 public static void main(String[] args) throws IOException {
   // Create a new file, by default canWrite=true,
   boolean 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: toURI()

   <source lang="java">
 

import java.io.File; import java.net.MalformedURLException; import java.net.URL; public class Main {

 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>
   
  
 
  



File: toURL()

   <source lang="java">
 

import java.io.File; import javax.swing.JFrame; public class MainClass extends JFrame {

 public static void main(String[] a) throws java.net.MalformedURLException {
   java.net.URL u = new File("GetResource.java").toURL();
   System.out.println(u);
 }

}


 </source>
   
  
 
  



new File(String name)

   <source lang="java">
 

/*

* Output:
* 

File Name:MainClass.java Path:MainClass.java Abs Path:C:\Java_Dev\workspace\cal\MainClass.java Parent:null does not exist is not writeable is not readable is a directoryfalse might be a named pipe is not absolute File last modified:0 File size:0 Bytes

* 
*  
*/

import java.io.File; public class MainClass {

   public static void main(String args[]) {
 File f1 = new File("MainClass.java");
 System.out.println("File Name:" + f1.getName());
 System.out.println("Path:" + f1.getPath());
 System.out.println("Abs Path:" + f1.getAbsolutePath());
 System.out.println("Parent:" + f1.getParent());
 System.out.println(f1.exists() ? "exists" : "does not exist");
 System.out.println(f1.canWrite() ? "is writeable" : "is not writeable");
 System.out.println(f1.canRead() ? "is readable" : "is not readable");
 System.out.println("is a directory" + f1.isDirectory() );
 System.out.println(f1.isFile() ? "is normal file" : "might be a named pipe");
 System.out.println(f1.isAbsolute() ? "is absolute" : "is not absolute");
 System.out.println("File last modified:" + f1.lastModified());
 System.out.println("File size:" + f1.length() + " Bytes");
   }

}


 </source>
   
  
 
  



new File(String parent, String child)

   <source lang="java">
 

import java.io.File; public class Main {

 public static void main(String[] a) {
   File myFile = new File("C:" + File.separator + "jdk1.5.0" + File.separator, "File.java");
   System.out.println(myFile.isAbsolute());
 }

}


 </source>
   
  
 
  



new File(URI uri)

   <source lang="java">
 
                      

import java.io.File; import java.net.URI; public class Main {

 public static void main(String[] a) throws Exception {
   File remoteFile = new File(new URI("file:///index.htm"));
 }

}


 </source>