/*
 * Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
 * 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.
 *
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/*
 * $Id: XPathFilterParameterSpec.java,v 1.4 2005/05/10 16:40:17 mullan Exp $
 */
package javax.xml.crypto.dsig.spec;

import javax.xml.crypto.dsig.Transform;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;

Parameters for the 
XPath Filtering Transform Algorithm.
The parameters include the XPath expression and an optional Map
of additional namespace prefix mappings. The XML Schema Definition of
the XPath Filtering transform parameters is defined as:

<element name="XPath" type="string"/>

Author:
Sean Mullan, JSR 105 Expert Group
See Also:
Transform
Since:
1.6/**
 * Parameters for the <a href="http://www.w3.org/TR/xmldsig-core/#sec-XPath">
 * XPath Filtering Transform Algorithm</a>.
 * The parameters include the XPath expression and an optional <code>Map</code>
 * of additional namespace prefix mappings. The XML Schema Definition of
 * the XPath Filtering transform parameters is defined as:
 * <pre><code>
 * &lt;element name="XPath" type="string"/&gt;
 * </code></pre>
 *
 * @author Sean Mullan
 * @author JSR 105 Expert Group
 * @since 1.6
 * @see Transform
 */
public final class XPathFilterParameterSpec implements TransformParameterSpec {

    private String xPath;
    private Map nsMap;

    
Creates an XPathFilterParameterSpec with the specified
XPath expression.
Params:
xPath – the XPath expression to be evaluated
Throws:
NullPointerException – if xPath is null/**
     * Creates an <code>XPathFilterParameterSpec</code> with the specified
     * XPath expression.
     *
     * @param xPath the XPath expression to be evaluated
     * @throws NullPointerException if <code>xPath</code> is <code>null</code>
     */
    public XPathFilterParameterSpec(String xPath) {
        if (xPath == null) {
            throw new NullPointerException();
        }
        this.xPath = xPath;
        this.nsMap = Collections.EMPTY_MAP;
    }

    
Creates an XPathFilterParameterSpec with the specified
XPath expression and namespace map. The map is copied to protect against
subsequent modification.
Params:
xPath – the XPath expression to be evaluated
namespaceMap – the map of namespace prefixes. Each key is a
   namespace prefix String that maps to a corresponding
   namespace URI String.
Throws:
NullPointerException – if xPath or
   namespaceMap are null
ClassCastException – if any of the map's keys or entries are not
   of type String/**
     * Creates an <code>XPathFilterParameterSpec</code> with the specified
     * XPath expression and namespace map. The map is copied to protect against
     * subsequent modification.
     *
     * @param xPath the XPath expression to be evaluated
     * @param namespaceMap the map of namespace prefixes. Each key is a
     *    namespace prefix <code>String</code> that maps to a corresponding
     *    namespace URI <code>String</code>.
     * @throws NullPointerException if <code>xPath</code> or
     *    <code>namespaceMap</code> are <code>null</code>
     * @throws ClassCastException if any of the map's keys or entries are not
     *    of type <code>String</code>
     */
    public XPathFilterParameterSpec(String xPath, Map namespaceMap) {
        if (xPath == null || namespaceMap == null) {
            throw new NullPointerException();
        }
        this.xPath = xPath;
        nsMap = new HashMap(namespaceMap);
        Iterator entries = nsMap.entrySet().iterator();
        while (entries.hasNext()) {
            Map.Entry me = (Map.Entry) entries.next();
            if (!(me.getKey() instanceof String) ||
                !(me.getValue() instanceof String)) {
                throw new ClassCastException("not a String");
            }
        }
        nsMap = Collections.unmodifiableMap(nsMap);
    }

    
Returns the XPath expression to be evaluated.
Returns:
the XPath expression to be evaluated/**
     * Returns the XPath expression to be evaluated.
     *
     * @return the XPath expression to be evaluated
     */
    public String getXPath() {
        return xPath;
    }

    
Returns a map of namespace prefixes. Each key is a namespace prefix
String that maps to a corresponding namespace URI
String.
 This implementation returns an 
unmodifiable map. 
Returns:
a Map of namespace prefixes to namespace URIs (may
   be empty, but never null)/**
     * Returns a map of namespace prefixes. Each key is a namespace prefix
     * <code>String</code> that maps to a corresponding namespace URI
     * <code>String</code>.
     * <p>
     * This implementation returns an {@link Collections#unmodifiableMap
     * unmodifiable map}.
     *
     * @return a <code>Map</code> of namespace prefixes to namespace URIs (may
     *    be empty, but never <code>null</code>)
     */
    public Map getNamespaceMap() {
        return nsMap;
    }
}