FileOutputStream

Here are the constructors of the FileOutputStream Class:

Constructors

FileOutputStream(String name) throws FileNotFoundException
    Creates an output stream that writes to the file. 

FileOutputStream(String name, boolean append) throws FileNotFoundException
    Creates an output stream. If append is true append bytes 
    to the end of the file. 

The second constructor opens a disk file for appending. Since we will always use DataOutputStream with a FileOutputStream we don't need to look at the methods (look in your on-line documentation if you want).