001    /**
002     * Copyright 2005-2012 The Kuali Foundation
003     *
004     * Licensed under the Educational Community License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     * http://www.opensource.org/licenses/ecl2.php
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    package org.kuali.rice.ksb.security;
017    
018    import java.security.Signature;
019    
020    /**
021     * Responsible for signing a message.  A reference is provided to the Signature to allow for population
022     * of the singnature from message data.  When this population of data is complete, the sign() method
023     * will sign the message according to the implementation.
024     * <br>
025     * Note that the interface itself does not provide any means of retrieving the message being signed.  It
026     * is up to the implementing classes to determine what consititutes "signing" of a message.
027     * 
028     * @author Kuali Rice Team (rice.collab@kuali.org)
029     */
030    public interface DigitalSigner {
031    
032            /**
033             * Retrieve a reference to Signature which will be used for signing.
034             */
035            public Signature getSignature();
036    
037            /**
038             * Sign the message using the Signature.  This method will not be called until all of the message data
039             * has been populated into the Signature.  After signing implementations may, for example, place the digital 
040             * signature in a header or perform whatever steps are required to successfully sign the message.
041             */
042            public void sign() throws Exception;
043            
044    }