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            public static final Singleton INSTANCE = new Singleton();
            private Singleton() { ... }
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            private static final Singleton INSTANCE = new Singleton();
            private Singleton() { ... }
            public static Singleton getInstance{}{return INSTANCE;} } ÕâÖÖ·½Ê½²»Óõ£ÐÄÐÔÄÜÎÊÌ⣬ÒòΪÏÖÔÚµÄJVM»á°Ñ¾ø´ó¶àÊýµÄ¾²Ì¬¹¤³§º¯Êý¸ÄΪÄÚÁª¡£´ËÍ⣬ÕâÖÖ·½·¨»¹¿ÉÒÔÔÚ²»¸Ä±äAPIµÄÇé¿ö϶Էµ»ØÖµ½øÐиı䣬¼´ÔÚÒÔºó¸ù¾ÝÐèÒªÊÇ·ñ·µ»ØµÚ¶þ¸öʵÀý£¬»òÊÇÿ¸öÏß³ÌÒ»¸öʵÀý¡£ ¶ÔÓÚÒÔÉÏÁ½ÖÖ·½·¨ÔÚ´®Ðл¯µÄʱºòҪעÒ⣬²»Äܽö½öÖ»¼ÓÉÏimplements Serializable½Ó¿Ú£¬ÕâÑù»áµ¼ÖÂÿ´Î·´ÐòÁл¯µÄʱºò´´½¨Ò»¸öжÔÏó£¬ÕâÑù¾Í²»ÊÇÕæÕýµÄsingletonÁË£¬½â¾öÕâ¸öÎÊÌâµÄ·½·¨ÊÇÔÚÉùÃ÷µÄʱºò¶Ôÿһ¸öfinal×ֶμÓÉÏtransient¹Ø¼ü×Ö£¬È»ºóÔÙʵÏÖÒ»¸öreadResolve·½·¨¡£ private Object readResolve() {
           return INSTANCE;
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