Java in a Nutshell, 5th Edition [Electronic resources]

This interface represents a DSA private key and provides direct access to the underlying key value. If you are working with a private key you know is a DSA key, you can cast the PrivateKey to a DSAPrivateKey.

public interface 
DSAPrivateKey  extends DSAKeyjava.security.PrivateKey {
// Public Constants
1.2   public static final long 
serialVersionUID ;  =7776497482533790279
// Public Instance Methods
java.math.BigInteger 
getX ( );  
}