FileOutputStream

Here are the constructors for FileOutputStream :

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. 

Use FileOutputStream to open a file, but use the methods of DataOutputStream for sending data into the stream.

DataOutputStream dataOut = new DataOutputStream( "myFile.dat" );