/**
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 * Unpublished - rights reserved under the Copyright Laws of the United States.
 * Copyright � 2003 Sun Microsystems, Inc. All rights reserved.
 * Copyright � 2005 BEA Systems, Inc. All rights reserved.
 *
 * Use is subject to license terms.
 *
 * This distribution may include materials developed by third parties. 
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 * Module Name   : JSIP Specification
 * File Name     : OptionTag.java
 * Author        : Phelim O'Doherty
 *
 *  HISTORY
 *  Version   Date      Author              Comments
 *  1.1     08/10/2002  Phelim O'Doherty    Initial version
 *~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 */
package javax.sip.header;

import java.text.ParseException;

/**
 * This interface represents methods for manipulating OptionTags
 * values for any header that contains an OptionTag value. Option tags are
 * unique identifiers used to designate new options (extensions) in SIP. Note
 * that these options appear as parameters in those header fields in an
 * option-tag = token form. Option tags are defined in standards track RFCs.
 * This is a change from past practice, and is instituted to ensure continuing
 * multi-vendor interoperability. 
 *
 * @see ProxyRequireHeader
 * @see RequireHeader
 * @see UnsupportedHeader
 * @see SupportedHeader
 *
 * @author BEA Systems, NIST
 * @version 1.2
 */

public interface OptionTag {

    /**
     * Sets the option tag value to the new supplied optionTag
     * parameter.
     *
     * @param optionTag - the new string value of the option tag.
     * @throws ParseException which signals that an error has been reached
     * unexpectedly while parsing the optionTag value.
     */
    public void setOptionTag(String optionTag) throws ParseException;

    /**
     * Gets the option tag of this OptionTag class.
     *
     * @return the string that identifies the option tag value.
     */
    public String getOptionTag();

}