/*
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package com.sun.xml.ws.security.policy;
import java.util.Iterator;

/**
 * Used to specify the header elements that the message MUST contain.
 * <p>
 * <pre><xmp>
 *      <sp:RequiredElements XPathVersion="xs:anyURI"? ... > 
 *          <sp:XPath>xs:string</sp:XPath>+ 
 *              ...
 *      </sp:RequiredElements>
 *</xmp></pre>
 * @author mayank.mishra@sun.com
 */
public interface RequiredElements extends Target {
    
    /**
     * Returns XPath Version in use.
     * @return xpath version 
     */
    public String getXPathVersion();
    
     /**
     * targets header elements message must contains .
     * @return {@link java.util.Iterator }
     */
    public Iterator getTargets();
    
}