Java OutputStreamWriter (OutputStream out, Charset cs) Constructor

public OutputStreamWriter(OutputStream out,     Charset cs)

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.nio.charset.Charset;
/* w  w  w  .jav a2 s  .c om*/
public class Main {

   public static void main(String[] args) {

      String s = "from java2s.com!";

      try {

         OutputStream os = new FileOutputStream("test.txt");
         OutputStreamWriter writer = new OutputStreamWriter(os,Charset.defaultCharset());

         FileInputStream in = new FileInputStream("test.txt");

         writer.write(s, 0, 5);

         writer.flush();

         for (int i = 0; i < 5; i++) {
            System.out.print((char) in.read());
         }
         writer.close();
         in.close();
      } catch (Exception ex) {
         ex.printStackTrace();
      }
   }
}