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

This interface defines an API that must be implemented by all elliptic curve private keys.

public interface 
ECPrivateKey  extends ECKeyjava.security.PrivateKey {
// Public Constants
public static final long 
serialVersionUID ;  =-7896394956925609184
// Public Instance Methods
java.math.BigInteger 
getS ( );  
}