鏋佸涓撴爮鎵撳寘-瀹炴椂鏇存柊闄勮祫鏂欐枃妗ｄ笅杞藉湴鍧€锛氱櫨搴︾綉鐩樹粠鏃犲埌鏈夎嚜宸卞啓鑷棆閿佸湪鎴戜滑鍐欏苟鍙戠▼搴忕殑鏃跺€欙紝涓€涓緢涓€涓父瑙佺殑闇€姹傛槸淇濊瘉鍦ㄦ煇涓椂鍒诲彧鏈変竴涓嚎绋嬫墽琛屾煇娈典唬鐮併€傝繖绉嶄唬鐮佺О涓轰复鐣屽尯锛岄€氬父淇濊瘉涓€娆″彧鏈変竴涓嚎绋嬫墽琛屼复鐣屽尯浠ｇ爜鐨勬柟寮忔槸閿侌煍掋€傚湪鏈枃涓紝鎴戜滑灏嗕粩缁嗗垎鏋愬拰瀛︿範鑷棆閿併€傛墍璋撹嚜鏃嬮攣鏄€氳繃涓€涓獁hile寰幆瀹屾垚鐨勶紝璁╂嫢鏈夐攣鐨勭嚎绋嬭繘鍏ヤ复鐣屽尯鎵ц浠ｇ爜锛岃娌℃湁閿佺殑绾跨▼鍋滄whiledead寰幆锛岃繖鍏跺疄灏辨槸绾跨▼鏈韩鍦╳hile寰幆涓€滆嚜鏃嬧€濓紝鎵€浠ヨ繖绉嶉攣绉颁负鑷棆閿併€傚師瀛愭€у湪璇磋嚜鏃嬮攣涔嬪墠杩樺緱鍏堣璇村師瀛愭€с€傛墍璋撳師瀛愭€э紝绠€鍗曠殑璇村氨鏄竴涓搷浣滆涔堜笉鍋氾紝瑕佷箞鍏ㄩ儴鍋氥€俤oingall鐨勬剰鎬濆氨鏄湪杩愯杩囩▼涓笉鑳借鎵撴柇銆傛瘮濡傜粰鍙橀噺鏁版嵁鍔犱竴锛屽垎涓夋锛氭暟鎹粠鍐呭瓨鍔犺浇鍒板瘎瀛樺櫒銆傚皢鏁版嵁鐨勫€煎鍔?銆傚皢寰楀埌鐨勭粨鏋滃啓鍥炲唴瀛樸€傚師瀛愭€ф槸鎸囦竴涓嚎绋嬪湪鎵ц鍔犱竴鎿嶄綔鏃朵笉鑳借鍏朵粬绾跨▼鎵撴柇銆傚彧鏈夌嚎绋嬪畬鎴愯繖涓変釜杩囩▼锛屽叾浠栫嚎绋嬫墠鑳藉鏁版嵁杩涜鎿嶄綔銆傜幇鍦ㄥ氨鐢ㄤ唬鐮佹潵浣撻獙涓€涓嬪惂銆傚湪Java涓紝鎴戜滑鍙互浣跨敤AtomicInteger瀵规暣鍨嬫暟鎹繘琛屽師瀛愭搷浣滐細importjava.util.concurrent.atomic.AtomicInteger;鍏叡绫籄tomicDemo{publicstaticvoidmain(String[]args)throwsInterruptedException{AtomicIntegerdata=newAtomicInteger();data.set(0);//鍒濆鍖栨暟鎹綅0Threadt1=newThread(()->{for(inti=0;i<100000;i++){data.addAndGet(1);//浠ュ師瀛愭柟寮忓皢1鍔犲埌鏁版嵁data}});Threadt2=newThread(()->{for(inti=0;i<100000;i++){data.addAndGet(1);//鍋滄瀵规暟鎹甦ata鐨勫師瀛愬姞1鎿嶄綔}});//鍚姩涓や釜绾跨▼t1.start();t2.start();//绛夊緟涓や釜绾跨▼瀹屾垚t1.join();t2.join();//鎵撳嵃鏈€缁堢粨鏋淪ystem.out.println(data);//200000}}澶嶅埗浠ｇ爜浠庝笂闈㈢殑浠ｇ爜鍒嗘瀽鎴戜滑鍙互鐭ラ亾锛屽鏋滄槸涓€涓櫘閫氱殑鏁村瀷鍙橀噺锛屽鏋滀袱涓嚎绋嬪悓鏃舵搷浣滐紝鏈€鍚庣殑缁撴灉浼氬皬浜?00000銆傛垜寮€濮嬪啓浜嗚嚜鏃嬮攣AtomicInteger绫汇€備簡瑙ｄ簡鍘熷瓙鎬х殑浣滅敤涔嬪悗锛屾垜浠幇鍦ㄤ簡瑙tomicInteger绫荤殑鍙︿竴涓師瀛愭搷浣溾€斺€攃ompareAndSet銆傛鎿嶄綔绉颁负姣旇緝鍜屼氦鎹?CAS)锛屽畠鏄師瀛愮殑銆?publicstaticvoidmain(String[]args){AtomicIntegeratomicInteger=newAtomicInteger();atomicInteger.set(0);atomicInteger.compareAndSet(0,1);}澶嶅埗浠ｇ爜compareAndSet鍑芥暟鐨勫惈涔夛細棣栧厛浼氭瘮杈冪涓€涓弬鏁帮紙瀵瑰簲涓婇潰浠ｇ爜涓?锛夊拰atomicInteger鐨勫€硷紝濡傛灉鐩哥瓑鍒欏仠姝㈤€氫俊锛屽嵆璁剧疆atomicInteger鐨勫€间负绗簩涓弬鏁帮紙瀵瑰簲涓婇潰浠ｇ爜涓?锛夛紝濡傛灉杩欎簺鎿嶄綔鎴愬姛锛屽垯compareAndSet鍑芥暟杩斿洖true锛屽鏋滄搷浣滃け璐ワ紝鍒欒繑鍥瀎alse锛屾搷浣滃け璐ュ彲鑳芥槸鍥犱负璇ュ€肩涓€涓弬鏁帮紙鏈熸湜鍊硷級鐨勪笉绛変簬atomicInteger锛屽鏋滅浉绛夛紝涔熷彲鑳芥槸鍥犱负淇敼atomicInteger鐨勫€兼椂澶辫触锛堝洜涓篛peration涓彲鑳芥湁澶氫釜绾跨▼锛岀敱浜庡師瀛愭€х殑瀛樺湪锛屽彧鏈変竴涓嚎绋嬫搷浣滃彲浠ヨ幏鑳滐級銆傝嚜鏃嬮攣鐨勫疄鐜板師鐞嗘垜浠彲浠ヤ娇鐢ˋtomicInteger绫绘潵瀹炵幇鑷棆閿併€傛垜浠彲浠ョ敤0鍊艰〃绀鸿В閿侊紝1鍊艰〃绀哄凡缁忎笂閿併€侫tomicInteger绫荤殑鍒濆鍊间负0锛屽湪鍔犻攣鐨勬椂鍊欙紝鎴戜滑鍙互浣跨敤浠ｇ爜atomicInteger.compareAndSet(0,1)鏉ュ畬鎴愩€傚墠闈㈡垜浠彁鍒板彧鏈変竴涓嚎绋嬪彲浠ュ畬鎴愯繖涓搷浣滐紝涔熷氨鏄鍙湁涓€涓嚎绋嬪彲浠ヨ皟鐢ㄨ繖琛屼唬鐮佸苟杩斿洖true锛屽叾浠栫嚎绋嬮兘杩斿洖false锛岃€岃繖浜涜繑鍥瀎alse鐨勭嚎绋嬫槸涓嶈兘杩涘叆涓寸晫鍖虹殑锛屾墍浠ユ垜浠渶瑕佽繖浜泃hreadstostopatatomicInteger.compareAndSet(0,1)杩欒浠ｇ爜涓嶈兘鍐嶇户缁墽琛屼簡锛屾垜浠彲浠ヤ娇鐢╳hile寰幆璁╄繖浜涚嚎绋嬩笉鏂殑鍋滃湪杩欓噷while(!value.compareAndSet(0,1));锛屽彧鏈夎繑鍥瀟rue鐨勭嚎绋嬪彲浠ヨ烦鍑哄惊鐜紝鍏朵粬绾跨▼浼氱户缁湪杩欓噷寰幆銆傛垜浠О杩欑琛屼负涓鸿嚜鏃嬶紝杩欑閿佷篃鍥犳涔熺О涓鸿嚜鏃嬮攣銆傚綋绾跨▼閫€鍑轰复鐣屽尯鏃讹紝闇€瑕侀噸鏂拌皟鏁撮攣鐘舵€佷负瑙ｉ攣鐘舵€併€傛垜浠彲浠ヤ娇鐢ㄤ唬鐮乿alue.compareAndSet(1,0);灏嗛攣瀹氱姸鎬佹仮澶嶅埌瑙ｉ攣鐘舵€併€傝繖鏍峰叾浠栬嚜鏃嬬嚎绋嬪氨鍙互鎷垮埌閿佽繘鍏ヤ复鐣屽尯銆傝嚜鏃嬮攣浠ｇ爜琛ュ叏importjava.util.concurrent.atomic.AtomicInteger;publicclassSpinLock{//0琛ㄧず瑙ｉ攣鐘舵€?/1琛ㄧず閿佸畾鐘舵€乸rotectedAtomicIntegervalue;publicSpinLock(){this.value=newAtomicInteger();//璁剧疆value鐨勫垵濮嬪€间负0琛ㄧず瑙ｉ攣鐘舵€乼his.value.set(0);}publicvoidlock(){//鍋滄鑷棆鎿嶄綔while(!value.compareAndSet(0,1));}publicvoidunlock(){//璁剧疆閿佺殑鐘舵€佷负瑙ｉ攣鐘舵€乿alue.compareAndSet(1,0);}}澶嶅埗浠ｇ爜涓婇潰鏄笂闈㈡垜浠畬鎴愮殑鑷棆閿佺殑浠ｇ爜锛岀湅璧锋潵鐪熺殑鏄お绠€鍗曚簡锛屼絾鏄‘瀹炲府鍔╂垜浠疄鐜颁簡涓€涓攣锛屽苟涓斿彲浠ュ湪瀹為檯鍦烘櫙涓娇鐢ㄣ€傜幇鍦ㄦ垜浠敤浠ｇ爜鏉ユ祴璇曚竴涓嬫垜浠笂闈㈠啓鐨勯攣銆傛祴璇曠▼搴忥細publicclassSpinLockTest{publicstaticintdata;publicstaticSpinLocklock=newSpinLock();publicstaticvoidadd(){for(inti=0;i<100000;i++){//閿佸彧鑳芥湁涓€涓嚎绋嬫墽琛宒ata++鎿嶄綔锛屽叾浠栫嚎绋嬪彧鑳藉仠姝hile寰幆lock.lock();鏁版嵁++锛沴ock.unlock();}}publicstaticvoidmain(String[]args)throwsInterruptedException{Thread[]threads=newThread[100];//璁剧疆100涓嚎绋媐or(inti=0;i<100;i++){threads[i]=newThread(SpinLockTest::add);}//鍚姩100涓嚎绋媐or(inti=0;i<100;i++){threads[i].start();}//绛夊緟瀵逛簬杩?00涓嚎绋嬪畬鎴恌or(inti=0;i<100;i++){threads[i].join();}System.out.println(data);//10000000}}澶嶅埗浠ｇ爜鍦ㄤ笂闈㈢殑浠ｇ爜鍒楄〃涓紝鎴戜滑浣跨敤浜?00涓嚎绋嬶紝鐒跺悗姣忎釜绾跨▼寰幆鎵ц100000娆ata++鎿嶄綔銆備笂闈唬鐮佹渶缁堣緭鍑?0000000绛変簬鎴戜滑绛夊緟鐨勭粨鏋滐紝璇存槑鎴戜滑瀹屾垚鐨勮嚜鏃嬮攣鏄纭殑銆傛垜寮€濮嬬紪鍐欏彲閲嶅叆鑷棆閿併€備笂闈㈠疄鐜扮殑鍙噸鍏ヨ嚜鏃嬮攣宸茬粡鍙互婊¤冻鎴戜滑鐨勪竴浜涘熀鏈渶姹傦紝鍗充竴娆″彧鑳芥湁涓€涓嚎绋嬫墽琛屼复鐣屽尯涓殑浠ｇ爜銆備絾鏄笂闈㈢殑浠ｇ爜涓嶈兘婊¤冻鍙噸鍏ョ殑瑕佹眰锛屼篃灏辨槸璇翠笂闈㈠啓鐨勮嚜鏃嬮攣涓嶆槸鍙噸鍏ョ殑鑷棆閿併€傚疄闄呬笂锛屽湪涓婇潰瀹屾垚鐨勮嚜鏃嬮攣涓噸鍏ヤ細浜х敓姝婚攣銆傛垜浠敤涓€娈典唬鐮佹潵妯℃嫙涓婇潰閲嶅叆瀵艰嚧鐨勬閿侊細publicstaticvoidadd(intstate)throwsInterruptedException{TimeUnit.SECONDS.sleep(1);濡傛灉锛堢姸鎬?=3锛墈lock.lock();System.out.println(Thread.currentThread().getName()+"\tEntercriticalsectionstate="+state);for(inti=0;i<10;i++)data++;add(state+1);//鍦ㄩ攣鐘舵€佷负1涔嬪墠鍋滄閫掑綊閲嶅叆锛屽洜涓烘湰绾跨▼宸茬粡杩涘叆涓寸晫鍖簂ock.unlock();}}澶嶅埗浠ｇ爜涓婇潰浠ｇ爜涓紝灏嗘垜浠紶鍏ョ殑鍙傛暟state鐨勫€煎姞涓?锛岀劧鍚庯紝濡傛灉绾跨▼鎵цfor寰幆鍚庡啀娆￠€掑綊璋冪敤add鍑芥暟锛屽垯state鐨勫€煎彉涓?锛屽鏋滄潯浠朵粛鐒舵弧瓒筹紝鍒欐湰绾跨▼涔熼渶瑕侀噸鏂拌幏鍙栭攣锛屼絾姝ゆ椂閿佺姸鎬佷负1銆佽繖涓嚎绋嬪凡缁忚幏鍙栬繃涓€娆￠攣锛屼絾鏄瓑寰呰嚜鏃嬮攣鐨勯攣鐘舵€佷负0锛屽洜涓哄彧鏈夎繖鏍蜂粬鎵嶈兘鍐嶆鑾峰彇閿佸苟杩涘叆涓寸晫鍖猴紝浣嗘槸鐜板湪閿佺姸鎬佷负1锛屼篃灏辨槸璇磋繖涓嚎绋嬭櫧鐒惰幏寰椾簡涓€娆￠攣锛屼絾鏄細鍋滄while寰幆锛屾案杩滀笉浼氬嚭鍘伙紝杩欏氨鏋勬垚浜嗘閿併€傚彲閲嶅叆鑷棆閿佺殑鎬濊矾閽堝浠ヤ笂鎯呭喌锛屾垜浠渶瑕佸畬鎴愪竴涓彲閲嶅叆鑷棆閿併€傛垜浠殑鎬濊矾澶ц嚧鏄繖鏍风殑锛氬湪鎴戜滑瀹屾垚鐨勮嚜鏃嬮攣涓紝鍙互娣诲姞涓や釜鍙橀噺锛宱wner涓€涓敤鏉ヤ繚瀛樺綋鍓嶆嫢鏈夐攣鐨勭嚎绋嬶紝count璁板綍褰撳墠绾跨▼杩涘叆閿佺殑娆℃暟銆傚鏋滅嚎绋嬭幏寰椾簡閿侊紝owner=Thread.currentThread()andcount=1銆傚綋绾跨▼涓嬫瑕佽幏寰楅攣鏃讹紝鍏堟鏌wner鏄惁鎸囧悜鑷繁锛岀劧鍚庣户缁惊鐜搷浣滐紝濡傛灉鏄紝鐩存帴鎵цcount++鎿嶄綔锛岀劧鍚庤繘鍏ヤ复鐣屽尯銆傚綋鎴戜滑閫€鍑轰复鐣屽尯鐨勬椂鍊欙紝濡傛灉count澶т簬1锛屽氨璇存槑绾跨▼閲嶆柊杩涘叆浜嗛攣锛屾墍浠ユ垜浠笉鑳界洿鎺ユ妸閿佺疆0锛屼篃灏辨槸瑙ｉ攣鐘舵€併€傝繖绉嶆儏鍐电洿鎺ユ墽琛宑ount--鎿嶄綔锛屽鏋渃ount绛変簬1锛岃鏄庣嚎绋嬪綋鍓嶇姸鎬佷笉鏄彲閲嶅叆鐘舵€侊紙閲嶅叆鍚庡彲鑳戒細閫掑綊杩斿洖锛夛紝鎵€浠ラ攣鐨勭姸鎬侀渶瑕佸湪閫€鍑轰复鐣屽尯鍓嶈缃负0锛屽嵆涓嶅姞閿併€備互渚垮叾浠栫嚎绋嬪彲浠ヨ幏鍙栭攣銆傞噸鍏ラ攣浠ｇ爜瀹屾垚锛氬畬鎴愮殑閲嶅叆閿佷唬鐮佸涓嬶細publicclassReentrantSpinLockextendsSpinLock{privateThreadowner;privateintcount;@Overridepublicvoidlock(){if(owner==null||owner!=Thread.currentThread()){while(!value.compareAndSet(0,1));owner=Thread.currentThread();count=1;}else{count++;}}@Overridepublicvoidunlock(){if(count==1){count=0;value.compareAndSet(1,0);}elsecount--;}}澶嶅埗浠ｇ爜涓嬮潰鎴戜滑鐢ㄩ€掑綊绋嬪簭鏉ラ獙璇佹垜浠啓鐨勫彲閲嶅叆鑷棆閿佹槸鍚﹁兘鎴愬姛銆傛祴璇曠▼搴忥細importjava.util.concurrent.TimeUnit;publicclassReentrantSpinLockTest{publicstaticintdata;publicstaticReentrantSpinLocklock=newReentrantSpinLock();publicstaticvoidadd(intstate)throwsInterruptedException{TimeUnit.SECONDS.sleep(1);if(state<=3){lock.lock();System.out.println(Thread.currentThread().getName()+"\t杩涘叆涓村鍖簊tate="+state);瀵逛簬(inti=0;i<10;i++)鏁版嵁++;娣诲姞锛堢姸鎬?1锛夛紱lock.unlock();}}publicstaticvoidmain(String[]args)throwsInterruptedException{Thread[]threads=newThread[10];for(inti=0;i<10;i++){threads[i]=newThread(newThread(()->{try{ReentrantSpinLockTest.add(1);}catch(InterruptedExceptione){e.printStackTrace();}},String.valueOf(i)));}for(inti=0;i<10;i++){threads[i].start();}for(inti=0;i<10;i++){threads[i].join();}System.out.println(data);}}澶嶅埗浠ｇ爜涓婇潰绋嬪簭鐨勮緭鍑猴細Thread-3杩涘叆涓寸晫鍖簊tate=1Thread-3杩涘叆涓寸晫鍖虹姸鎬?2Thread-3杩涘叆涓寸晫鍖虹姸鎬?3Thread-0杩涘叆涓寸晫鍖虹姸鎬?1Thread-0杩涘叆涓寸晫鍖虹姸鎬?2Thread-0杩涘叆涓寸晫鍖虹姸鎬?3Thread-9杩涘叆涓寸晫鍖虹姸鎬?1Thread-9杩涘叆涓寸晫鍖虹姸鎬?2Thread-9杩涘叆涓寸晫鍖虹姸鎬?3Thread-4杩涘叆涓寸晫鍖虹姸鎬?1Thread-4杩涘叆涓寸晫鍖虹姸鎬?2Thread-4杩涘叆涓寸晫鍖虹姸鎬?3Thread-7杩涘叆涓寸晫鍖虹姸鎬?1Thread-7杩涘叆涓寸晫鍖虹姸鎬?2Thread-7杩涘叆涓寸晫鍖虹姸鎬?3Thread-8杩涘叆涓寸晫鍖虹姸鎬?1Thread-8杩涘叆涓寸晫鍖虹姸鎬?2Thread-8杩涘叆涓寸晫鍖虹姸鎬?3Thread-5杩涘叆涓寸晫鍖虹姸鎬?1Thread-5杩涘叆涓寸晫鍖虹姸鎬乻tate=2Thread-5杩涘叆涓寸晫鍖簊tate=3Thread-2杩涘叆涓寸晫鍖簊tate=1Thread-2杩涘叆涓寸晫鍖簊tate=2Thread-2杩涘叆涓寸晫鍖簊tate=3Thread-6杩涘叆涓寸晫鍖簊tate=1Thread-6杩涘叆涓寸晫鍖簊tate=2Thread-6杩涘叆涓寸晫鍖虹姸鎬?3Thread-1杩涘叆涓寸晫鍖虹姸鎬?1Thread-1杩涘叆涓寸晫鍖虹姸鎬?2Thread-1杩涘叆涓寸晫鍖虹姸鎬?3300澶嶅埗浠ｇ爜浠庝笂闈㈢殑杈撳嚭鎴戜滑鍙互鐭ラ亾锛屽綋涓€涓嚎绋嬪彲浠ユ嬁鍒伴攣鐨勬椂鍊欏氨鍙互鍋滄閲嶅叆锛屾渶鍚庤緭鍑虹殑缁撴灉涔熸槸姝ｇ‘鐨勶紝鎵€浠ラ獙璇佷簡鎴戜滑鍐欑殑鍙噸鍏ヨ嚜鏃嬮攣鏄湁鏁堢殑锛佸皬缁撳湪杩欑瘒鏂囩珷涓紝鎴戜富瑕佷粙缁嶄簡鑷棆閿佸拰鍙噸鍏ヨ嚜鏃嬮攣鐨勫師鐞嗭紝骞跺啀娆″畬鎴愩€傚叾瀹炰唬鐮佹瘮杈冪畝鍗曘€傚叧閿槸澶у闇€瑕佹槑鐧藉叾涓殑閫昏緫锛氭墍璋撹嚜鏃嬮攣灏辨槸while寰幆缁撴潫鍚庯紝璁╂嬁鍒伴攣鐨勭嚎绋嬭繘鍏ヤ复鐣屽尯鎵ц浠ｇ爜锛岃娌℃湁鑾峰緱閿佺殑绾跨▼鍋滄锛屾寰幆鍙互閲嶅叆銆傞噸鍏ョ殑鎰忔€濇槸涓€涓嚎绋嬫浘缁忕珵浜夎繃涓€鎶婇攣銆傜珵浜夊畬杩欎釜閿佸悗锛岄渶瑕侀噸鏂拌繘鍏ヤ复鐣屽尯浠ｇ爜銆傚鏋滆繖涓嚎绋嬪彲浠ヤ繚璇佸彲浠ラ噸鏂拌繘鍏ヤ复鐣屽尯锛岃繖灏卞彨鍋氬彲閲嶅叆銆傛垜浠湪瀹炵幇鑷棆閿佺殑鏃跺€欙紝浣跨敤鐨勬槸AtomicInteger绫伙紝鎴戜滑浣跨敤0鍜?杩欎袱涓€兼潵琛ㄧず鏃犻攣鍜岄攣琚崰鐢ㄤ袱绉嶇姸鎬併€傚湪鑾峰彇閿佺殑鏃跺€欙紝鎴戜滑浣跨敤while寰幆涓嶆柇鐨勮繘琛孋AS鎿嶄綔銆傜洿鍒版搷浣滄垚鍔熻繑鍥瀟rue锛岄噴鏀鹃攣鏃朵娇鐢–AS灏嗛攣鐨勭姸鎬佷粠1鍙樹负0銆傚疄鐜板彲閲嶅叆閿佹渶閲嶈鐨勬槸闇€瑕佽褰曟槸鍝釜绾跨▼鑾峰緱浜嗛攣锛岃繕闇€瑕佽褰曡幏寰椾簡澶氬皯娆￠攣锛屽洜涓烘垜浠渶瑕佸湪瑙ｉ攣鐨勬椂鍊欒繘琛屽垽鏂紝鐒跺悗count鐨勭姸鎬?1鍙互灏嗛攣Set鐨勭姸鎬佷粠1鍙樹负0銆?/p>
