JAVA EE: Java Tutorial : Java IO (FileReader constructor accepts file object)

Thursday 28 July 2016

Java Tutorial : Java IO (FileReader constructor accepts file object)

Click here to watch in Youtube :
https://www.youtube.com/watch?v=R-P_eWw7pzY&list=UUhwKlOVR041tngjerWxVccw

myfile.txt

Peter is coming to India.

FileReaderDemo.java

import java.io.File;
import java.io.FileReader;
import java.io.IOException;

/*
 * public FileReader(File file) throws
 *                   FileNotFoundException
 * 
 * Parameters: 
 * ----------
 * 
 * file - the File to read from
 */

public class FileReaderDemo
{

    public static void main(String[] args) throws IOException
    {
        FileReaderDemo fileReaderDemo = new FileReaderDemo();
        fileReaderDemo.readFile();
    }

    private void readFile() throws IOException
    {
        FileReader fileReader = null;

        try
        {
            File file = new File("myfile.txt");
            /*
             * Creates a new FileReader, given the File to
             * read from.
             */
            fileReader = new FileReader(file);
            int i;

            /*
             * Reads a single character or -1 if the end of
             * the stream has been reached
             */
            while ((i = fileReader.read()) != -1)
            {
                System.out.print((char) i);
            }
        }
        finally
        {
            if (fileReader != null)
            {
                /*
                 * Closes the stream and releases any system
                 * resources associated with it. Once the
                 * stream has been closed, further read(),
                 * ready(), mark(), reset(), or skip()
                 * invocations will throw an IOException.
                 * Closing a previously closed stream has no
                 * effect.
                 */
                fileReader.close();
            }
        }
    }
}