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myfile.txt

Peter is coming to India.

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;

/*
 * public FileOutputStream(File file, boolean append)
 *                          throws FileNotFoundException
 * 
 * Parameters:
 * ----------- 
 * 
 * file - the file to be opened for writing.
 * 
 * append - if true, then bytes will be written to the
 * end of the file rather than the beginning
 */

public class FileOutputStreamDemo
{

    public static void main(String[] args) throws IOException
    {
        FileOutputStreamDemo fileOutputStreamDemo = new FileOutputStreamDemo();
        fileOutputStreamDemo.writeFile();
    }

    private void writeFile() throws IOException
    {
        FileOutputStream fileOutputStream = null;

        try
        {
            File file = new File("myfile.txt");

            /*
             * Creates a file output stream to write to the
             * file represented by the specified File
             * object. If the second argument is true, then
             * bytes will be written to the end of the file
             * rather than the beginning.
             */

            fileOutputStream = new FileOutputStream(file, true);
            String str = "Peter is coming to India.\n";

            /*
             * Converting string into byte array
             */
            byte[] byteArray = str.getBytes();

            /*
             * Writes b.length bytes from the specified byte
             * array to this file output stream.
             */
            fileOutputStream.write(byteArray);
            System.out.println("Successfully written to the file.");
        }
        finally
        {
            if (fileOutputStream != null)
            {
                /*
                 * Closes this file output stream and
                 * releases any system resources associated
                 * with this stream.
                 */
                fileOutputStream.close();
            }
        }
    }

}