澶у巶Java闈㈣瘯锛氶潰璇曞畼vs姘磋揣绋嬪簭鍛樿阿椋炴満鐨勬妧鏈鍐砛n
绗竴杞細Java鍩虹涓庨泦鍚堟鏋禱n
闈㈣瘯瀹�锛氳阿椋炴満锛屼綘濂姐�傛垜鏄粖澶╃殑闈㈣瘯瀹橈紝鎴戜滑寮�濮嬬涓�杞潰璇曘�傞鍏堬紝璇蜂綘绠�鍗曚粙缁嶄竴涓婣rrayList鍜孡inkedList鐨勫尯鍒�俓n璋㈤鏈�锛氳繖涓畝鍗曪紒ArrayList鏄暟缁勫垪琛紝LinkedList鏄摼琛ㄥ垪琛ㄣ�侫rrayList鍍忎竴鍒楃伀杞︼紝杞﹀帰鏄繛缁帓鍒楃殑锛汱inkedList鍍忎竴涓茬弽鐝狅紝姣忛鐝嶇彔閮界敤绾胯繛鐫�銆傚浜嗭紝ArrayList鏌ュ緱蹇紝LinkedList鎻掑緱蹇紒
闈㈣瘯瀹�锛氾紙鐐瑰ご锛夊洖绛斿緱涓嶉敊锛屽熀鏈蹇垫纭�傞偅涔圚ashMap鐨勬暟鎹粨鏋勬槸鎬庢牱鐨勶紵
璋㈤鏈�锛欻ashMap鍟婏紝灏辨槸涓�涓ぇ鎶藉眽锛佷綘鎶婁笢瑗挎斁杩涘幓锛屽畠浼氭牴鎹挜鍖欑殑鍝堝笇鍊煎喅瀹氭斁鍦ㄥ摢涓皬鏍煎瓙閲屻�傚鏋滀袱涓笢瑗跨殑閽ュ寵绠楀嚭鏉ヤ竴鏍凤紝瀹冧滑灏卞湪鍚屼竴涓牸瀛愰噷鎺掓帓闃熴�俓n闈㈣瘯瀹�锛氬鏋淗ashMap鍙戠敓鍝堝笇鍐茬獊锛屽畠鏄�庝箞澶勭悊鐨勶紵
璋㈤鏈�锛氳繖涓�...鍡�...瀹冧細鎵撶數璇濈粰119锛熶笉瀵逛笉瀵癸紝搴旇鏄�...瀹冧細鎵句釜鏇村ぇ鐨勬娊灞夛紒鎴栬�呰鍚庢潵鐨勪笢瑗垮幓闅斿閭诲眳瀹讹紵
闈㈣瘯瀹�锛氾紙鐨辩湁锛夌湅鏉ヤ綘瀵笻ashMap鐨勯摼鍦板潃娉曞拰绾㈤粦鏍戣浆鎹㈡満鍒朵笉澶竻妤氥�傛垜浠户缁紝ArrayList鐨勬墿瀹规満鍒舵槸鎬庢牱鐨勶紵
璋㈤鏈�锛氭墿瀹瑰晩锛佸氨鍍忔垜瀹剁殑鍐扮锛屼笢瑗挎斁涓嶄笅浜嗭紝灏变拱涓洿澶х殑鍐扮锛岀劧鍚庢妸鎵�鏈変笢瑗挎惉杩囧幓銆備笉杩囪閲嶆柊鏁寸悊涓�涓嬶紝涓嶇劧鎵句笉鍒颁笢瑗夸簡銆俓n闈㈣瘯瀹�锛氬熀鏈�濊矾鏄鐨勶紝浣嗗叿浣撴墿瀹瑰洜瀛愭槸1.5鍊嶃�傛垜浠繘鍏ヤ笅涓�杞�俓n
绗簩杞細澶氱嚎绋嬩笌JVM
闈㈣瘯瀹�锛氱幇鍦ㄩ棶涓�浜涘绾跨▼鐩稿叧鐨勯棶棰樸�備粈涔堟槸绾跨▼瀹夊叏锛焅n璋㈤鏈�锛氱嚎绋嬪畨鍏ㄥ氨鏄�...澶氫釜绾跨▼涓�璧峰共娲荤殑鏃跺�欎笉浼氭墦鏋讹紒灏卞儚椋熷爞鎵撻キ锛屽鏋滃ぇ瀹堕兘鎺掗槦灏卞畨鍏紝濡傛灉鏈変汉鎻掗槦灏变細涔便�俓n闈㈣瘯瀹�锛氾紙寰瑧锛夋瘮鍠诲緢褰㈣薄銆傞偅synchronized鍜孯eentrantLock鏈変粈涔堝尯鍒紵
璋㈤鏈�锛歴ynchronized鏄嚜鍔ㄦ尅锛孯eentrantLock鏄墜鍔ㄦ尅锛佽嚜鍔ㄦ尅绠�鍗曚絾鍔熻兘灏戯紝鎵嬪姩鎸″鏉備絾鍙互鐜╂紓绉�...鍝︿笉锛屾槸鍙互瀹炵幇鏇村鏉傜殑鍔熻兘锛乗n闈㈣瘯瀹�锛欽VM鍐呭瓨鍖哄煙鍒掑垎浜嗚В鍚楋紵
璋㈤鏈�锛欽VM鍐呭瓨鍟�...鏈夊爢銆佹爤銆佹柟娉曞尯...鍫嗘槸鏀惧璞＄殑澶т粨搴擄紝鏍堟槸鏀惧眬閮ㄥ彉閲忕殑灏忔娊灞夛紝鏂规硶鍖烘槸鏀剧被淇℃伅鐨勫浘涔﹂锛乗n闈㈣瘯瀹�锛氫笉閿欍�傞偅鍨冨溇鍥炴敹绠楁硶鏈夊摢浜涳紵
璋㈤鏈�锛氬瀮鍦惧洖鏀�...鏈夋爣璁版竻闄ゃ�佹爣璁版暣鐞嗐�佸鍒剁畻娉�...鏍囪娓呴櫎灏卞儚鍦ㄥぇ琛椾笂鎹″瀮鍦撅紝鏍囪鏁寸悊灏辨槸鎶婂瀮鍦鹃兘鎺ㄥ埌涓�杈癸紝澶嶅埗绠楁硶灏辨槸鎶婂共鍑�鐨勪笢瑗挎惉鍒版柊瀹讹紝鏃у涓嶈浜嗭紒
闈㈣瘯瀹�锛氱嚎绋嬫睜鐨勬牳蹇冨弬鏁版湁鍝簺锛焅n璋㈤鏈�锛氱嚎绋嬫睜鍙傛暟...鏈夋牳蹇冪嚎绋嬫暟銆佹渶澶х嚎绋嬫暟銆侀槦鍒�...鍡�...杩樻湁鎷掔粷绛栫暐锛佸氨鍍忓叕鍙告嫑浜猴紝鏍稿績鍛樺伐鏄寮忓伐锛屼复鏃跺伐鏄渶澶х嚎绋嬫暟锛屼换鍔″お澶氬氨鎺掗槦锛岄槦涔熸帓涓嶄笅灏辨嫆缁濓紒
闈㈣瘯瀹�锛氱悊瑙ｅ熀鏈纭�傛垜浠繘鍏ョ涓夎疆銆俓n
绗笁杞細妗嗘灦涓庝腑闂翠欢
闈㈣瘯瀹�锛歋pring涓瑽ean鐨勭敓鍛藉懆鏈熶簡瑙ｅ悧锛焅n璋㈤鏈�锛欱ean鐨勭敓鍛藉懆鏈�...鍑虹敓鈫掗暱澶р啋宸ヤ綔鈫掗��浼戯紒鍏蜂綋灏辨槸瀹炰緥鍖栤啋灞炴�ц祴鍊尖啋鍒濆鍖栤啋浣跨敤鈫掗攢姣併�俓n闈㈣瘯瀹�锛歋pringBoot鑷姩閰嶇疆鍘熺悊鏄粈涔堬紵
璋㈤鏈�锛氳繖涓�...瀹冩湁涓瓟娉曠洅瀛愶紒浣犳斁杩涘幓闇�瑕佺殑渚濊禆锛岀洅瀛愪細鑷姩鍙樺嚭閰嶇疆锛佸疄闄呬笂鏄湁寰堝@EnableAutoConfiguration鍦ㄨ儗鍚庡共娲汇�俓n闈㈣瘯瀹�锛歁yBatis涓�#{}鍜�${}鐨勫尯鍒紵
璋㈤鏈�锛�#{}鏄畨鍏ㄦ敞灏勶紝${}鏄洿鎺ユ嫾鎺ワ紒#{}浼氭秷姣掞紝${}涓嶆秷姣掞紝瀹规槗寰楃梾...鍝︿笉锛屾槸瀹规槗SQL娉ㄥ叆锛乗n闈㈣瘯瀹�锛歊abbitMQ鐨勫伐浣滄ā寮忔湁鍝簺锛焅n璋㈤鏈�锛歊abbitMQ...鏈夌畝鍗曟ā寮忋�佸伐浣滈槦鍒椼�佸彂甯冭闃呫�佽矾鐢便�佷富棰�...灏卞儚閫佸揩閫掞紝鍙互鐐瑰鐐归�侊紝鍙互骞挎挱锛屽彲浠ユ寜鍦板潃閫侊紝鍙互鎸夊叧閿瓧閫侊紒
闈㈣瘯瀹�锛歊edis鎸佷箙鍖栨満鍒舵湁鍝袱绉嶏紵
璋㈤鏈�锛歊DB鍜孉OF锛丷DB鏄媿鐓х墖锛孉OF鏄鏃ヨ銆傛媿鐓х墖鏄畾鏈熸媿锛岃鏃ヨ鏄瘡浠朵簨閮借涓嬫潵锛乗n闈㈣瘯瀹�锛氬ソ鐨勶紝浠婂ぉ鐨勯潰璇曞氨鍒拌繖閲屻�傛垜浠渶瑕佺患鍚堣瘎浼颁竴涓嬶紝浣犲洖鍘荤瓑閫氱煡鍚с�俓n璋㈤鏈�锛氬ソ鐨勫ソ鐨勶紝璋㈣阿闈㈣瘯瀹橈紒鎴戝洖鍘诲ソ濂藉涔狅紒
鎶�鏈瓟妗堣В鏋怽n
1. ArrayList vs LinkedList
璇︾粏瑙ｆ瀽锛歕n-ArrayList锛氬熀浜庡姩鎬佹暟缁勫疄鐜帮紝闅忔満璁块棶蹇�(O(1))锛屼絾鎻掑叆鍒犻櫎闇�瑕佺Щ鍔ㄥ厓绱�(O(n))
- LinkedList锛氬熀浜庡弻鍚戦摼琛ㄥ疄鐜帮紝鎻掑叆鍒犻櫎蹇�(O(1))锛屼絾闅忔満璁块棶闇�瑕侀亶鍘�(O(n))
- 鎵╁鏈哄埗锛欰rrayList榛樿瀹归噺10锛屾墿瀹规椂newCapacity = oldCapacity + (oldCapacity >> 1)锛屽嵆1.5鍊峔n
2. HashMap鏁版嵁缁撴瀯
璇︾粏瑙ｆ瀽锛歕n-鏁版嵁缁撴瀯锛氭暟缁�+閾捐〃+绾㈤粦鏍戯紙JDK8+锛塡n-鍝堝笇鍐茬獊瑙ｅ喅锛氶摼鍦板潃娉曪紝鍐茬獊鏃跺舰鎴愰摼琛紝閾捐〃闀垮害鈮�8涓旀暟缁勯暱搴︹墺64鏃惰浆涓虹孩榛戞爲
- 鎵╁鏈哄埗锛氳礋杞藉洜瀛�0.75锛屾墿瀹归槇鍊间负瀹归噺*璐熻浇鍥犲瓙锛屾墿瀹规椂rehash
3. 绾跨▼瀹夊叏涓庨攣
璇︾粏瑙ｆ瀽锛歕n-synchronized锛欽VM绾у埆閿侊紝鑷姩閲婃斁閿侊紝鍙噸鍏ワ紝闈炲叕骞抽攣
- ReentrantLock锛欰PI绾у埆閿侊紝闇�瑕佹墜鍔ㄩ噴鏀撅紝鍙噸鍏ワ紝鍙疄鐜板叕骞抽攣锛屾敮鎸丆ondition
- 绾跨▼姹犲弬鏁�锛歕n - corePoolSize锛氭牳蹇冪嚎绋嬫暟
- maximumPoolSize锛氭渶澶х嚎绋嬫暟
- keepAliveTime锛氱┖闂茬嚎绋嬪瓨娲绘椂闂碶n - workQueue锛氫换鍔￠槦鍒梊n - RejectedExecutionHandler锛氭嫆缁濈瓥鐣n
4. JVM鍐呭瓨妯″瀷
璇︾粏瑙ｆ瀽锛歕n-鍫�锛氬瓨鏀惧璞″疄渚嬶紝GC涓昏鍖哄煙
- 鏍�锛氬瓨鍌ㄥ眬閮ㄥ彉閲忋�佹搷浣滄暟鏍堛�佹柟娉曞嚭鍙ｇ瓑
- 鏂规硶鍖�锛氬瓨鍌ㄧ被淇℃伅銆佸父閲忋�侀潤鎬佸彉閲廫n-绋嬪簭璁℃暟鍣�锛氬綋鍓嶇嚎绋嬫墽琛岀殑瀛楄妭鐮佽鍙穃n-鏈湴鏂规硶鏍�锛歂ative鏂规硶鏈嶅姟
5. 鍨冨溇鍥炴敹绠楁硶
璇︾粏瑙ｆ瀽锛歕n-鏍囪-娓呴櫎锛氭爣璁板瓨娲诲璞★紝娓呴櫎鏈爣璁板璞★紝浜х敓鍐呭瓨纰庣墖
- 鏍囪-鏁寸悊锛氭爣璁板瓨娲诲璞★紝鍚戜竴绔Щ鍔紝鏁寸悊鍐呭瓨
- 澶嶅埗绠楁硶锛氬皢鍐呭瓨鍒嗕负涓ゅ潡锛屽彧鐢ㄤ竴鍧楋紝鍥炴敹鏃跺皢瀛樻椿瀵硅薄澶嶅埗鍒板彟涓�鍧梊n-鍒嗕唬鏀堕泦锛氭柊鐢熶唬鐢ㄥ鍒剁畻娉曪紝鑰佸勾浠ｇ敤鏍囪-娓呴櫎鎴栨爣璁�-鏁寸悊
6. Spring妗嗘灦
璇︾粏瑙ｆ瀽锛歕n-Bean鐢熷懡鍛ㄦ湡锛氬疄渚嬪寲鈫掑睘鎬ц祴鍊尖啋BeanPostProcessor鍓嶇疆澶勭悊鈫掑垵濮嬪寲鈫払eanPostProcessor鍚庣疆澶勭悊鈫掍娇鐢ㄢ啋閿�姣乗n-SpringBoot鑷姩閰嶇疆锛氶�氳繃@EnableAutoConfiguration寮曞叆META-INF/spring.factories涓殑閰嶇疆绫伙紝鏉′欢娉ㄨВ@Conditional鎺у埗閰嶇疆鐢熸晥
7. MyBatis鍙傛暟澶勭悊
璇︾粏瑙ｆ瀽锛歕n- **#{}**锛氶缂栬瘧澶勭悊锛岄槻姝QL娉ㄥ叆锛屼細鑷姩娣诲姞寮曞彿
- **${}**锛氬瓧绗︿覆鏇挎崲锛岀洿鎺ユ嫾鎺QL锛屾湁SQL娉ㄥ叆椋庨櫓
8. RabbitMQ宸ヤ綔妯″紡
璇︾粏瑙ｆ瀽锛歕n-绠�鍗曟ā寮�锛氫竴瀵逛竴锛屼竴涓敓浜ц�呬竴涓秷璐硅�匼n-宸ヤ綔闃熷垪锛氫竴瀵瑰锛屼竴涓敓浜ц�呭涓秷璐硅�呯珵浜夋秷璐筡n-鍙戝竷璁㈤槄锛氫竴涓秷鎭澶氫釜娑堣垂鑰呮秷璐癸紝閫氳繃Exchange骞挎挱
- 璺敱妯″紡锛氭牴鎹畆outing key璺敱娑堟伅鍒版寚瀹氶槦鍒梊n-涓婚妯″紡锛氫娇鐢ㄩ�氶厤绗﹀尮閰峳outing key
9. Redis鎸佷箙鍖朶n璇︾粏瑙ｆ瀽锛歕n-RDB锛氬畾鏃跺揩鐓э紝浜岃繘鍒舵枃浠讹紝鎭㈠蹇紝鍙兘涓㈠け鏈�鍚庝竴娆″揩鐓у悗鐨勬暟鎹甛n-AOF锛氳褰曟瘡涓啓鎿嶄綔锛屽彲閰嶇疆鍚屾棰戠巼锛屾暟鎹畬鏁存�ч珮锛屾枃浠惰緝澶n
10. 璁捐妯″紡涓嶥DD
棰濆琛ュ厖锛歕n-鍗曚緥妯″紡锛氱‘淇濅竴涓被鍙湁涓�涓疄渚媆n-宸ュ巶妯″紡锛氬垱寤哄璞¤�屼笉鏆撮湶鍒涘缓閫昏緫
- 绛栫暐妯″紡锛氬畾涔夌畻娉曟棌锛屽皝瑁呭彉鍖朶n-DDD锛堥鍩熼┍鍔ㄨ璁★級锛氶�氳繃缁熶竴璇█銆佽仛鍚堟牴銆佸�煎璞°�侀鍩熸湇鍔＄瓑鏋勫缓澶嶆潅涓氬姟绯荤粺
鎬荤粨
鏈闈㈣瘯娑电洊浜咼ava寮�鍙戠殑鏍稿績鐭ヨ瘑鐐癸紝浠庡熀纭�闆嗗悎鍒板绾跨▼锛屼粠JVM鍒版鏋朵腑闂翠欢銆傝阿椋炴満铏界劧鏈変簺鍥炵瓟姣旇緝骞介粯锛屼絾鍩烘湰姒傚康杩樻槸鏈夌殑銆傚浜庢兂杩涘叆澶у巶鐨凧ava寮�鍙戣�咃紝闇�瑕佹繁鍏ョ悊瑙ｈ繖浜涙妧鏈偣锛屼笉浠呰鐭ュ叾鐒讹紝杩樿鐭ュ叾鎵�浠ョ劧銆傚缓璁粨鍚堝疄闄呴」鐩粡楠岋紝娣卞叆婧愮爜瀛︿範锛屾墠鑳藉湪闈㈣瘯涓父鍒冩湁浣欍�俓n娉細鏈枃閫氳繃骞介粯鐨勯潰璇曞満鏅紝璁╄鑰呭湪杞绘澗鐨勬皼鍥翠腑瀛︿範Java鏍稿績鎶�鏈紝閫傚悎鍚勫眰娆ava寮�鍙戣�呴槄璇诲涔犮��
