Write File using OneByte in java

import java.io.*;

public class OneByteTest2 {
public static void main(String[] args) throws Exception{
FileOutputStream fos1 = new FileOutputStream(FileDescriptor.out);
BufferedOutputStream bos1 = new BufferedOutputStream(fos1,2048);
DataOutputStream dos1 = new DataOutputStream(bos1);

dos1.writeInt(20);
dos1.writeDouble(12.34);
dos1.flush();
dos1.writeChar('A');
dos1.writeByte('\n');
dos1.writeChar('B');
dos1.close();

FileOutputStream fos2 = new FileOutputStream(new File("C:\\FileTest\\bbb.txt"));
BufferedOutputStream bos2 = new BufferedOutputStream(fos2,2048);
DataOutputStream dos2 = new DataOutputStream(bos2);

dos2.writeInt(20);
dos2.writeDouble(12.34);
dos2.writeChar('A');
dos2.writeByte('\n');
dos2.writeChar('B');
dos2.close();







}

}