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褰撳涓嚎绋嬫洿鏂扮敤浜庢敹闆嗙粺璁℃暟鎹瓑鐩殑鐨勫叕鍏辨€诲拰鏃讹紝姝ょ被閫氬父浼樹簬{@linkAtomicLong}锛岃€屼笉鏄敤浜庣粏绮掑害鍚屾*鎺у埗銆傚湪浣庢洿鏂扮珵浜変笅锛岃繖涓や釜绫诲叿鏈夌浉浼肩殑*鐗规€с€備絾鍦ㄩ珮绔炰簤涓嬶紝*姝ょ被鐨勯鏈熷悶鍚愰噺鏄庢樉鏇撮珮锛屼絾浠ｄ环鏄洿楂樼殑绌洪棿*娑堣€椼€備粠鎻忚堪涓彲浠ョ湅鍑猴紝LongAdder鏇村鐨勬槸鐢ㄤ簬鏀堕泦缁熻鏁版嵁锛岃€屼笉鏄疐ine-grained鍚屾鎺у埗銆侺ongAdder鍜孉tomicLong鍦ㄤ綆骞跺彂鏃舵病鏈夊お澶у尯鍒紝浣嗘槸鍦ㄩ珮骞跺彂鏃讹紝LongAdder閫氳繃鐗虹壊绌洪棿鏉ユ彁楂樺悶鍚愰噺銆傜畝鍗曚粙缁嶄竴涓婰ongAdder鐨勮璁℃€濊矾銆侺ongAdder浼氬皢鍊兼斁鍏ヤ竴涓暟缁勪腑浣滀负鏁扮粍鍏冪礌鐨勫€硷紝鐒跺悗灏嗗苟鍙戠嚎绋嬪垎閰嶇粰鍏朵腑涓€涓€艰繘琛岃绠楋紝鏈€鍚庡皢杩欎簺鍊肩浉鍔犲緱鍒版渶缁堝€笺€傚浘鐗囨憳鑷猍Xiaojiajava]AtomicLong鍙互涓㈠純锛岃鏀圭敤LongAdder锛堟垨浣跨敤LongAccumulator锛夈€傛帴涓嬫潵锛岃鎴戜滑鐪嬩竴涓嬫簮浠ｇ爜銆傝鎴戜滑浠ュ閲忎负璧风偣銆俻ublicclassLongAdderextendsStriped64implementsSerializable{...publicvoidincrement(){add(1L);}publicvoidadd(longx){Cell[]as;闀縝,v;璇犻噴绫?缁嗚優涓€涓紱if((as=cells)!=null||!casBase(b=base,b+x)){booleanuncontended=true;if(as==null||(m=as.length-1)<0||(a=as[getProbe()&m])==null||!(uncontended=a.cas(v=a.鍊硷紝v+x)))longAccumulate(x,null,uncontended);}}}abstractclassStriped64extendsNumber{/***鍩哄€硷紝涓昏鍦ㄦ病鏈変簤鐢ㄦ椂浣跨敤锛屼絾涔熶綔涓鸿〃鍒濆鍖栫珵璧涙湡闂寸殑鍥為€€銆傞€氳繃CAS鏇存柊銆?/transientvolatilelongbase;@sun.misc.ContendedstaticfinalclassCell{volatilelongvalue;鍗曞厓鏍硷紙闀縳锛墈鍊?x锛泒finalbooleancas(longcmp,longval){杩斿洖UNSAFE.compareAndSwapLong(this,valueOffset,cmp,val);}//涓嶅畨鍏ㄦ満鍒秔rivatestaticfinalsun.misc.UnsafeUNSAFE;绉佹湁闈欐€佹渶缁堥暱鍊煎亸绉婚噺锛涢潤鎬亄灏濊瘯{涓嶅畨鍏?sun.misc.Unsafe.getUnsafe();绫??>ak=Cell.class;valueOffset=UNSAFE.objectFieldOffset(ak.getDeclaredField("value"));}catch(Exceptione){thrownewError(e);}}}}浠庝唬鐮佺9琛屽彲浠ョ湅鍑篊ell鏁扮粍宸茬粡杩涜浜嗙┖鎿嶄綔锛岃鏄庝竴寮€濮嬫暟缁勬病鏈夊垵濮嬪寲锛岀劧鍚巆asBase(b=base,b+x)杩涜cas鎿嶄綔锛岃繖涓猙ase鐨勫€兼槸鍦↙ongAdder鐖剁被Striped64涓畾涔夌殑锛屼粠娉ㄩ噴淇℃伅鏉ョ湅锛屽氨鏄痓ase鍊笺€傚綋绾跨▼娌℃湁浜夌敤鏃朵娇鐢ㄣ€傜湅鍒拌繖閲岋紝鎴戜滑鍙互寰楀嚭涓€涓粨璁猴細LongAdder涓嶄細鍦ㄤ竴寮€濮嬬嚎绋嬬珵浜夋槸鏃犵珵浜夌殑鎯呭喌涓嬬洿鎺ヤ娇鐢–ell鏁扮粍锛岃€屾槸浣跨敤volatile鍩哄彉閲忔潵瀛樺偍鏃犵珵浜夋潵琛ㄧず绔炰簤鏄惁婵€鐑堛€傛帴涓嬫潵鐨勪唬鐮佹槸褰撳墠闈㈢殑鏉′欢casBase琛ㄧず绔炰簤澶辫触鏃躲€備笅闈㈢殑鍒ゆ柇鏉′欢鏄珵浜夊垰鍒氬彂鐢燂紝Cell鏁扮粍杩樻病鏈夊垱寤烘垨鑰呯嚎绋嬫墍鍦ㄧ殑Cell鐨刢as鎿嶄綔澶辫触锛岃〃鏄庡瓨鍦ㄧ珵浜夈€傞潪甯告縺鐑堬紝杩欐椂鍊欓渶瑕佽皟鐢╨ongAccumulate鏂规硶鏉ュ垱寤哄拰鎵╁睍Cell鏁扮粍銆傛渶鍚庯紝褰撻渶瑕佸彇鍊肩殑鏃跺€欙紝闇€瑕佽皟鐢╯um鏂规硶锛屼篃灏辨槸灏咰ell鏁扮粍鐨勫€肩浉鍔犲緱鍒版渶缁堢殑缁撴灉銆俻ublicclassLongAdderextendsStriped64implementsSerializable{publiclongsum(){Cell[]as=cells;缁嗚優涓€涓?闀挎€诲拰=鍩烘暟锛沬f(as!=null){for(inti=0;i