java.lang.Object
   |
   +----java.io.OutputStream
           |
           +----java.io.FilterOutputStream
                   |
                   +----java.io.DataOutputStream
 public class DataOutputStream
  
 extends FilterOutputStream
  
 implements DataOutput
A data input stream lets an application write primitive Java data types to an output stream in a portable way. An application can then use a data input stream to read the data back in.