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019    
020    
021    package org.apache.mailet.base;
022    
023    import java.util.Date;
024    
025    import javax.mail.internet.MailDateFormat;
026    
027    
028    /**
029     * A thread safe wrapper for the <code>javax.mail.internet.MailDateFormat</code> class.
030     *
031     */
032    public class RFC822DateFormat extends SynchronizedDateFormat {
033        /**
034         * A static instance of the RFC822DateFormat, used by toString
035         */
036        private static RFC822DateFormat instance;
037    
038        static {
039            instance = new RFC822DateFormat();
040        }
041    
042        /**
043         * This static method allows us to format RFC822 dates without
044         * explicitly instantiating an RFC822DateFormat object.
045         *
046         * @return java.lang.String
047         * @param d Date
048         *
049         * @deprecated This method is not necessary and is preserved for API
050         *             backwards compatibility.  Users of this class should
051         *             instantiate an instance and use it as they would any
052         *             other DateFormat object.
053         */
054        public static String toString(Date d) {
055            return instance.format(d);
056        }
057    
058        /**
059         * Constructor for RFC822DateFormat
060         */
061        public RFC822DateFormat() {
062            super(new MailDateFormat());
063        }
064    }