Deebugging help java exam's coming?

import java.io.*;


class PrimitiveDemo


{


public static void main(String args[]) throws IOException


{


File primitive=new File("pri.txt");


FileOutputStream fos=new FileOutputStream(primitive);


DataOutputStream dos=new DataOutputStream(fos);


dos.writeInt(5);


dos.writeDouble(0.5);


dos.writeBoolean(false);


dos.writeChar('c');


dos.close();


fos.close();


// Read data from file


FileInputStream fis=new FileInputStream(primitive);


DataInputStream dis=new DataInputStream(fis);


System.out.println(dis.readInt());


System.out.println(dis.readDouble());


System.out.println(dis.readBoolean());


System.out.println(dis.readChar());


dos.close();


dos.close();


}


}

Deebugging help java exam's coming?
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