1   /*
    2    * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
    3    * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
    4    *
    5    * This code is free software; you can redistribute it and/or modify it
    6    * under the terms of the GNU General Public License version 2 only, as
    7    * published by the Free Software Foundation.  Oracle designates this
    8    * particular file as subject to the "Classpath" exception as provided
    9    * by Oracle in the LICENSE file that accompanied this code.
   10    *
   11    * This code is distributed in the hope that it will be useful, but WITHOUT
   12    * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   13    * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   14    * version 2 for more details (a copy is included in the LICENSE file that
   15    * accompanied this code).
   16    *
   17    * You should have received a copy of the GNU General Public License version
   18    * 2 along with this work; if not, write to the Free Software Foundation,
   19    * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   20    *
   21    * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   22    * or visit www.oracle.com if you need additional information or have any
   23    * questions.
   24    */
   25   /*
   26    * $Id: KeyInfo.java,v 1.7 2005/05/10 16:35:34 mullan Exp $
   27    */
   28   package javax.xml.crypto.dsig.keyinfo;
   29   
   30   import java.util.List;
   31   import javax.xml.crypto.MarshalException;
   32   import javax.xml.crypto.XMLCryptoContext;
   33   import javax.xml.crypto.XMLStructure;
   34   
   35   /**
   36    * A representation of the XML <code>KeyInfo</code> element as defined in
   37    * the <a href="http://www.w3.org/TR/xmldsig-core/">
   38    * W3C Recommendation for XML-Signature Syntax and Processing</a>.
   39    * A <code>KeyInfo</code> contains a list of {@link XMLStructure}s, each of
   40    * which contain information that enables the recipient(s) to obtain the key
   41    * needed to validate an XML signature. The XML Schema Definition is defined as:
   42    *
   43    * <pre>
   44    * &lt;element name="KeyInfo" type="ds:KeyInfoType"/&gt;
   45    * &lt;complexType name="KeyInfoType" mixed="true"&gt;
   46    *   &lt;choice maxOccurs="unbounded"&gt;
   47    *     &lt;element ref="ds:KeyName"/&gt;
   48    *     &lt;element ref="ds:KeyValue"/&gt;
   49    *     &lt;element ref="ds:RetrievalMethod"/&gt;
   50    *     &lt;element ref="ds:X509Data"/&gt;
   51    *     &lt;element ref="ds:PGPData"/&gt;
   52    *     &lt;element ref="ds:SPKIData"/&gt;
   53    *     &lt;element ref="ds:MgmtData"/&gt;
   54    *     &lt;any processContents="lax" namespace="##other"/&gt;
   55    *     &lt;!-- (1,1) elements from (0,unbounded) namespaces --&gt;
   56    *   &lt;/choice&gt;
   57    *   &lt;attribute name="Id" type="ID" use="optional"/&gt;
   58    * &lt;/complexType&gt;
   59    * </pre>
   60    *
   61    * A <code>KeyInfo</code> instance may be created by invoking one of the
   62    * {@link KeyInfoFactory#newKeyInfo newKeyInfo} methods of the
   63    * {@link KeyInfoFactory} class, and passing it a list of one or more
   64    * <code>XMLStructure</code>s and an optional id parameter;
   65    * for example:
   66    * <pre>
   67    *   KeyInfoFactory factory = KeyInfoFactory.getInstance("DOM");
   68    *   KeyInfo keyInfo = factory.newKeyInfo
   69    *      (Collections.singletonList(factory.newKeyName("Alice"), "keyinfo-1"));
   70    * </pre>
   71    *
   72    * <p><code>KeyInfo</code> objects can also be marshalled to XML by invoking
   73    * the {@link #marshal marshal} method.
   74    *
   75    * @author Sean Mullan
   76    * @author JSR 105 Expert Group
   77    * @since 1.6
   78    * @see KeyInfoFactory#newKeyInfo(List)
   79    * @see KeyInfoFactory#newKeyInfo(List, String)
   80    */
   81   public interface KeyInfo extends XMLStructure {
   82   
   83       /**
   84        * Returns an {@link java.util.Collections#unmodifiableList unmodifiable
   85        * list} containing the key information. Each entry of the list is
   86        * an {@link XMLStructure}.
   87        *
   88        * <p>If there is a public subclass representing the type of
   89        * <code>XMLStructure</code>, it is returned as an instance of that
   90        * class (ex: an <code>X509Data</code> element would be returned as an
   91        * instance of {@link javax.xml.crypto.dsig.keyinfo.X509Data}).
   92        *
   93        * @return an unmodifiable list of one or more <code>XMLStructure</code>s
   94        *    in this <code>KeyInfo</code>. Never returns <code>null</code> or an
   95        *    empty list.
   96        */
   97       List getContent();
   98   
   99       /**
  100        * Return the optional Id attribute of this <code>KeyInfo</code>, which
  101        * may be useful for referencing this <code>KeyInfo</code> from other
  102        * XML structures.
  103        *
  104        * @return the Id attribute of this <code>KeyInfo</code> (may be
  105        *    <code>null</code> if not specified)
  106        */
  107       String getId();
  108   
  109       /**
  110        * Marshals the key info to XML.
  111        *
  112        * @param parent a mechanism-specific structure containing the parent node
  113        *    that the marshalled key info will be appended to
  114        * @param context the <code>XMLCryptoContext</code> containing additional
  115        *    context (may be null if not applicable)
  116        * @throws ClassCastException if the type of <code>parent</code> or
  117        *    <code>context</code> is not compatible with this key info
  118        * @throws MarshalException if the key info cannot be marshalled
  119        * @throws NullPointerException if <code>parent</code> is <code>null</code>
  120        */
  121       void marshal(XMLStructure parent, XMLCryptoContext context)
  122           throws MarshalException;
  123   }