/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements. See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership. The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
/*
 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
 */
/*
 * $Id: DOMStructure.java 1092655 2011-04-15 10:24:18Z coheigea $
 */
package javax.xml.crypto.dom;

import org.w3c.dom.Node;
import javax.xml.crypto.XMLStructure;
import javax.xml.crypto.dsig.XMLSignature;

/**
 * A DOM-specific {@link XMLStructure}. The purpose of this class is to
 * allow a DOM node to be used to represent extensible content (any elements
 * or mixed content) in XML Signature structures.
 *
 * <p>If a sequence of nodes is needed, the node contained in the
 * <code>DOMStructure</code> is the first node of the sequence and successive
 * nodes can be accessed by invoking {@link Node#getNextSibling}.
 *
 * <p>If the owner document of the <code>DOMStructure</code> is different than 
 * the target document of an <code>XMLSignature</code>, the   
 * {@link XMLSignature#sign(XMLSignContext)} method imports the node into the 
 * target document before generating the signature.
 *
 * @author Sean Mullan
 * @author JSR 105 Expert Group
 */
public class DOMStructure implements XMLStructure {

    private final Node node;

    /**
     * Creates a <code>DOMStructure</code> containing the specified node.
     *
     * @param node the node
     * @throws NullPointerException if <code>node</code> is <code>null</code>
     */
    public DOMStructure(Node node) {
        if (node == null) {
            throw new NullPointerException("node cannot be null");
        }
        this.node = node;
    }

    /**
     * Returns the node contained in this <code>DOMStructure</code>.
     *
     * @return the node
     */
    public Node getNode() {
        return node;
    }

    /**
     * @throws NullPointerException {@inheritDoc}
     */
    public boolean isFeatureSupported(String feature) {
        if (feature == null) {
            throw new NullPointerException();
        } else {
            return false;
        }
    }
}
