How to read and write files in Java

[BansiJ]

I am creating a program where the code is able to read a user specified file and also capable of writing few lines in the same file. But how will this be possible using JAVA? How can I code Java for read and write functions? Can anyone explain me the working of this module?

[fellah]

import java.io.*;

public class ReadWriteFile
{
	public static void main (String args[])
	{
		FileInputStream input;		
		FileOutputStream output;		
		try
		{
		    input = new FileInputStream ("testfile.txt");
		    System.out.println( new DataInputStream(input).readLine() );
		    input.close();		
		}
		try
		{
		    output = new FileOutputStream ("testfile.txt");
		    new PrintStream(output).println ("hello world!");
		    output.close();		
		}
		catch (IOException e)
		{
			System.err.println ("Unable to read/write file");
			System.exit(-1);
		}
	}	
}

[Katty]

Here is the code for reading the from the file:

public void read(String myFile) throws IOException{
	FileReader readFile = null;
	BufferedReader readBuffer;
	String line;
	readFile = new FileReader(myFile);
        readBuffer = new BufferedReader(readFile);
        line="";   
        while(line != null){        
        	line = readBuffer.readLine();		
		System.out.println(line);
        }        
        readBuffer.close();
}

[Modifier]

Here is what I found on SUN.com. To open a file for reading, you can use the newInputStream method. This method returns an unbuffered input stream for reading bytes from the file.

    Path file = ...;
    InputStream in = null;
    try {
        in = file.newInputStream();
        BufferedReader reader = new BufferedReader(new InputStreamReader(in));
        String line = null;
        while ((line = reader.readLine()) != null) {
            System.out.println(line);
        }
    } catch (IOException x) {
        System.err.println(x);
    } finally {
        if (in != null) in.close();
    }