How to write in a File and Read from a File in Java

import java.io.*;
public class FileWriter{

public FileWriter(){

try{
FileOutputStream fos =new FileOutputStream("data.txt");
BufferedOutputStream bos= new BufferedOutputStream(fos);
DataOutputStream dos= new DataOutputStream(bos);


dos.writeUTF("Testing the file program");


dos.close();
fos.close();


FileInputStream fis =new FileInputStream("data.txt");
BufferedInputStream bis= new BufferedInputStream(fis);
DataInputStream dis= new DataInputStream(bis);
String s=dis.readUTF();
System.out.println(s);

dis.close();
fis.close();
}catch(Exception e){}


}//end of constrctr

public static void main(String m[]){

new FileWriter();



}//end of main
}//end of class