Files reading and writing in Java

Lot of times we need to read or write files using java code.

Here is an useful example:

import java.io.*;

class FileCopyUtility
{
   public static void main(String[] args)
   {
      try
      {
         //create the file objects from the source and target file names
  File fileToRead  = new File("source.txt");
         File fileToWrite = new File("target.txt");

         //create File Input stream reader and writer
  FileInputStream streamIn   = new FileInputStream(fileToRead);
         FileOutputStream streamOut = new FileOutputStream(fileToWrite);

         int c;
        //this loop will run till there is something to read in the input stream
 while ((c = streamIn.read()) != -1)
         {
            //read stream will be written to the output stream
  streamOut.write(c);
         }

         //close the file input and output streams once the copy operation is done.
  streamIn.close();
         streamOut.close();
      }
      catch (FileNotFoundException e)
      {
         System.err.println("FileCopy: " + e);
      }
      catch (IOException e)
      {
         System.err.println("FileCopy: " + e);
      }
   }
}