/* * Copyright (c) 1997, 1999, Oracle and/or its affiliates. All rights reserved. * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation.  Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ package java.security; import java.security.spec.AlgorithmParameterSpec; /** * <p> This class defines the <i>Service Provider Interface</i> (<b>SPI</b>) * for the <code>KeyPairGenerator</code> class, which is used to generate * pairs of public and private keys. * * <p> All the abstract methods in this class must be implemented by each * cryptographic service provider who wishes to supply the implementation * of a key pair generator for a particular algorithm. * * <p> In case the client does not explicitly initialize the KeyPairGenerator * (via a call to an <code>initialize</code> method), each provider must * supply (and document) a default initialization. * For example, the <i>Sun</i> provider uses a default modulus size (keysize) * of 1024 bits. * * @author Benjamin Renaud * * * @see KeyPairGenerator * @see java.security.spec.AlgorithmParameterSpec */ public abstract class KeyPairGeneratorSpi {     /**     * Initializes the key pair generator for a certain keysize, using     * the default parameter set.     *     * @param keysize the keysize. This is an     * algorithm-specific metric, such as modulus length, specified in     * number of bits.     *     * @param random the source of randomness for this generator.     *     * @exception InvalidParameterException if the <code>keysize</code> is not     * supported by this KeyPairGeneratorSpi object.     */    public abstract void initialize(int keysize, SecureRandom random);     /**     * Initializes the key pair generator using the specified parameter     * set and user-provided source of randomness.     *     * <p>This concrete method has been added to this previously-defined     * abstract class. (For backwards compatibility, it cannot be abstract.)     * It may be overridden by a provider to initialize the key pair     * generator. Such an override     * is expected to throw an InvalidAlgorithmParameterException if     * a parameter is inappropriate for this key pair generator.     * If this method is not overridden, it always throws an     * UnsupportedOperationException.     *     * @param params the parameter set used to generate the keys.     *     * @param random the source of randomness for this generator.     *     * @exception InvalidAlgorithmParameterException if the given parameters     * are inappropriate for this key pair generator.     *     * @since 1.2     */    public void initialize(AlgorithmParameterSpec params,                           SecureRandom random)        throws InvalidAlgorithmParameterException {            throw new UnsupportedOperationException();    }     /**     * Generates a key pair. Unless an initialization method is called     * using a KeyPairGenerator interface, algorithm-specific defaults     * will be used. This will generate a new key pair every time it     * is called.     *     * @return the newly generated <tt>KeyPair</tt>     */    public abstract KeyPair generateKeyPair();}