This abstract class defines the service-provider interface for Signature. A security provider must implement a concrete subclass of this class for each digital signature algorithm it supports. Applications never need to use or subclass this class.

public abstract class SignatureSpi {
// Public Constructors
     public SignatureSpi( );  
// Public Methods Overriding Object
     public Object clone( ) throws CloneNotSupportedException;  
// Protected Instance Methods
1.4  protected AlgorithmParameters engineGetParameters( );  
     protected abstract void engineInitSign(PrivateKey privateKey) 
        throws InvalidKeyException;  
     protected void engineInitSign(PrivateKey privateKey, SecureRandom random) 
        throws InvalidKeyException;  
     protected abstract void engineInitVerify(PublicKey publicKey) 
        throws InvalidKeyException;  
     protected void engineSetParameter(java.security.spec.
        AlgorithmParameterSpec params) 
        throws InvalidAlgorithmParameterException;  
     protected abstract byte[ ] engineSign( ) throws SignatureException;  
     protected int engineSign(byte[ ] outbuf, int offset, int len) 
        throws SignatureException;  
5.0  protected void engineUpdate(java.nio.ByteBuffer input);  
     protected abstract void engineUpdate(byte b) throws SignatureException;  
     protected abstract void engineUpdate(byte[ ] b, int off, int len) 
        throws SignatureException;  
     protected abstract boolean engineVerify(byte[ ] sigBytes) 
        throws SignatureException;  
1.4  protected boolean engineVerify(byte[ ] sigBytes, int offset, int length) 
        throws SignatureException;  
// Protected Instance Fields
     protected SecureRandom appRandom;  
// Deprecated Protected Methods
#    protected abstract Object engineGetParameter(String param) 
        throws InvalidParameterException;  
#    protected abstract void engineSetParameter(String param, Object value) 
        throws InvalidParameterException;  
}

Subclasses

Signature