Java.io.File.sync() Method

Description

The java.io.File.sync() method forces all system buffers to synchronize with the underlying device.

Declaration

Following is the declaration for java.io.File.sync() method:

public void sync()

Parameters

• NA

Return Value

The method does not return any value.

Exception

• SyncFailedException -- This exception is thrown when the buffer cannot be flushed or because the system cannot guarantee synchronization of all the buffers with the physical media.

Example

The following example shows the usage of java.io.File.sync() method.

package com.tutorialspoint;

import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.FileOutputStream;

public class FileDemo {
   public static void main(String[] args) {
      
      FileInputStream fis = null;
      FileOutputStream fos = null;
      FileDescriptor fd = null;
      byte[] b = {65,66,67,68,69,70};
      
      try{
         fos = new FileOutputStream("c:/java test.txt");
         fd = fos.getFD();
         
         // writes byte to file output stream
         fos.write(b);
         
         // flush data from the stream into the buffer
         fos.flush();
         
         // confirms data to be written to the disk
         fd.sync();
         
         // create input stream
         fis = new FileInputStream("c:/java test.txt");
         
         int value = 0;
         
         // for every available bytes
         while((value=fis.read())!= -1)
         {
            // converts bytes to char
            char c = (char)value;
            
            // prints char
            System.out.print(c);
         }
         // print
         System.out.print("\nSync() successfully executed!!");
         
      }catch(Exception e){
         // if any error occurs
         e.printStackTrace();
      }finally{
         // releases system resources
         if(fos!=null)
            fos.close();
         if(fis!=null)
            fis.close();
      }
   }
}

Let us compile and run the above program, this will produce the following result:

ABCDEF
Sync() successfully executed!!