/*

 * 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

 * particular file as subject to the "Classpath" exception as provided

 *

 * 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.

 *

 */

/*

 * $Id: DigestMethod.java,v 1.6 2005/05/10 16:03:46 mullan Exp $

 */

package javax.xml.crypto.dsig;

import javax.xml.crypto.AlgorithmMethod;

import javax.xml.crypto.XMLStructure;

import javax.xml.crypto.dsig.spec.DigestMethodParameterSpec;

import java.security.spec.AlgorithmParameterSpec;

/**

 * A representation of the XML <code>DigestMethod</code> element as

 * defined in the <a href="http://www.w3.org/TR/xmldsig-core/">

 * W3C Recommendation for XML-Signature Syntax and Processing</a>.

 * The XML Schema Definition is defined as:

 * <p>

 * <pre>

 *   <element name="DigestMethod" type="ds:DigestMethodType"/>

 *     <complexType name="DigestMethodType" mixed="true">

 *       <sequence>

 *         <any namespace="##any" minOccurs="0" maxOccurs="unbounded"/>

 *           <!-- (0,unbounded) elements from (1,1) namespace -->

 *       </sequence>

 *       <attribute name="Algorithm" type="anyURI" use="required"/>

 *     </complexType>

 * </pre>

 *

 * A <code>DigestMethod</code> instance may be created by invoking the

 * {@link XMLSignatureFactory#newDigestMethod newDigestMethod} method

 * of the {@link XMLSignatureFactory} class.

 *

 * @author Sean Mullan

 * @author JSR 105 Expert Group

 * @since 1.6

 * @see XMLSignatureFactory#newDigestMethod(String, DigestMethodParameterSpec)

 */

public interface DigestMethod extends XMLStructure, AlgorithmMethod {

    /**

     * The <a href="http://www.w3.org/2000/09/xmldsig#sha1">

     * SHA1</a> digest method algorithm URI.

     */

    static final String SHA1 = "http://www.w3.org/2000/09/xmldsig#sha1";

    /**

     * The <a href="http://www.w3.org/2001/04/xmlenc#sha256">

     * SHA256</a> digest method algorithm URI.

     */

    static final String SHA256 = "http://www.w3.org/2001/04/xmlenc#sha256";

    /**

     * The <a href="http://www.w3.org/2001/04/xmlenc#sha512">

     * SHA512</a> digest method algorithm URI.

     */

    static final String SHA512 = "http://www.w3.org/2001/04/xmlenc#sha512";

    /**

     * The <a href="http://www.w3.org/2001/04/xmlenc#ripemd160">

     * RIPEMD-160</a> digest method algorithm URI.

     */

    static final String RIPEMD160 = "http://www.w3.org/2001/04/xmlenc#ripemd160";

    /**

     * Returns the algorithm-specific input parameters associated with this

     * <code>DigestMethod</code>.

     *

     * <p>The returned parameters can be typecast to a {@link

     * DigestMethodParameterSpec} object.

     *

     * @return the algorithm-specific parameters (may be <code>null</code> if

     *    not specified)

     */

    AlgorithmParameterSpec getParameterSpec();

}