java FileWriter and FileReader

import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
public class FWFRDemo
{
final static String MSG = "Test message";
public static void main(String[] args) throws IOException
{
try (FileWriter fw = new FileWriter("temp"))
{
fw.write(MSG, 0, MSG.length());
}
char[] buf = new char[MSG.length()];
try (FileReader fr = new FileReader("temp"))
{
fr.read(buf, 0, MSG.length());
System.out.println(buf);
}
}
}