馃敟 鈥?strong>鈥嬩綘鏄笉鏄篃濂藉锛氳final鏍囪鐨勬柟娉曪紝鐪熺殑鍍忎紶璇翠腑閭ｆ牱鍒€鏋笉鍏ュ悧锛熲€?/strong>鈥?浠婂ぉ鍜变滑灏辨幇寮€浜嗘弶纰庝簡鑱婅繖涓簨锛佹垜鍒氬紑濮嬪Java鐨勬椂鍊欙紝鐩潃杩欎釜final鍏抽敭瀛楃洿鎸犲ご鈥斺€斿畠鍒板簳鍦ㄥ畧鎶や粈涔堢瀵嗭紵鏉ワ紝鎼釜灏忔澘鍑冲潗濂斤紝鍜变滑杈瑰枬濂惰尪杈硅В瀵唦

馃毃銆愮伒榄備笁闂€戝厛鎼炴噦鍩烘湰姒傚康

鈥?strong>鈥?. final鏂规硶闀垮暐鏍凤紵涓句釜鏍楀瓙馃尠鈥?/strong>鈥?br/> 绠€鍗曟潵璇达紝灏辨槸鏂规硶澹版槑鍓嶅姞涓猣inal锛屾瘮濡傦細
public final void payVerify(){...}
杩欏氨鍍忕粰鏂规硶璐翠簡灏佹潯锛屽憡璇夋墍鏈変汉锛氣€滆繖涓柟娉曟垜鎵垮寘浜嗭紝璋侀兘鍒兂鍔紒鈥?/p>

鈥?strong>鈥?. 鑳戒笉鑳介噸鍐欙紵璇曡繃鎵嶇煡閬擄紒鈥?/strong>鈥?br/> 鍜变滑鐩存帴涓婁唬鐮侀獙璇侊紙鎺忓嚭閿洏锛夛細

java澶嶅埗
class Parent {
    public final void show(){...}
}
class Child extends Parent {
    public void show(){...} // 杩欓噷浼氱洿鎺ユ姤閿欙紒
}

鈥?strong>鈥嬪彯锛佺紪璇戝櫒褰撳満缈昏劯锛氣€?/strong>鈥?"cannot override show()..." 鐪嬭娌★紵杩炲皾璇曠殑鏈轰細閮戒笉缁欙紒

鈥?strong>鈥?. 閭ｇ户鎵垮憿锛熻兘涓嶈兘缁ф壙锛熲€?/strong>鈥?br/> 杩欓噷鏈変釜瀹规槗娣锋穯鐨勭偣锛氣€?strong>鈥嬬户鎵?鈮?閲嶅啓鈥?/strong>鈥?/p>

• 鉁旓笍 瀛愮被鍙互鐩存帴璋冪敤鐖剁被鐨刦inal鏂规硶
• 鉂?浣嗕笉鑳芥敼鍐欏畠鐨勫疄鐜?br/> 灏卞儚浣犵户鎵夸簡浣犵埜鐨勪紶瀹跺疂锛屽彲浠ラ殢渚跨敤锛屼絾瑕佹槸鎯崇粰浼犲瀹濆埢涓秱楦︼紵闂ㄩ兘娌℃湁锛?/li>

馃攳銆愮湡鐩告椂鍒汇€戜负浠€涔圝ava瑕佽杩欎釜闄愬埗锛?/h3>

鍜变滑鐢ㄤ釜瀵规瘮琛ㄧ湅寰楁洿鏄庣櫧锛?/p>

鎯呭喌	鏅€氭柟娉?/th>	final鏂规硶
鑳藉惁琚瓙绫讳慨鏀?/td>	闅忎究鏀癸紝鐖卞拫鏀瑰拫鏀?/td>	鎯抽兘鍒兂锛?/td>
璁捐鎰忓浘	鎻愪緵鎵╁睍鍙兘鎬?/td>	淇濇姢鏍稿績閫昏緫
鎬ц兘浼樺寲	鍙兘琚姩鎬佺粦瀹?/td>	瀹规槗瑙﹀彂鍐呰仈浼樺寲
浣跨敤鍦烘櫙	甯歌涓氬姟閫昏緫	鏀粯楠岃瘉/鍔犲瘑绠楁硶绛夊叧閿€昏緫

鈥?strong>鈥嬸煉?閲嶇偣鏉ヤ簡锛氣€?/strong>鈥?br/> Java璁捐鑰呮悶杩欎釜闄愬埗锛屽叾瀹炴槸涓轰簡淇濇姢绋嬪簭鐨?涓冨"銆備妇涓湡瀹炴渚嬧€斺€斺€?strong>鈥婼tring绫荤殑hashCode()鏂规硶灏辨槸final鐨勨€?/strong>鈥嬶紝涓哄暐锛熷洜涓哄鏋滈殢渚胯浜烘敼鍝堝笇绠楁硶锛屾暣涓泦鍚堟鏋堕兘寰椾贡濂楋紒

---

馃洝锔忋€愮敓瀛樻寚鍗椼€戣繖浜涘満鏅繀椤荤敤final鏂规硶

鈥?strong>鈥嬪満鏅?锛氭敮浠樼郴缁熺殑鏈€鍚庨槻绾库€?/strong>鈥?br/> 鎯宠薄浣犲湪寮€鍙戝井淇℃敮浠橈細

java澶嶅埗
public final boolean checkBalance(){
    // 浣欓鏍￠獙鏍稿績閫昏緫
}

瑕佹槸杩欎釜鏍￠獙鏂规硶鑳借閲嶅啓锛屼笉娉曞垎瀛愬垎鍒嗛挓鑳戒吉閫犱綑棰濓紒杩欏彲涓嶆槸闂圭潃鐜╃殑~

鈥?strong>鈥嬪満鏅?锛氬伐鍏风被闃查瓟鏀光€?/strong>鈥?br/> 鐪嬭繖涓粡鍏歌璁★細

java澶嶅埗
public class MathUtils {
    private MathUtils(){} // 鏋勯€犲櫒绉佹湁鍖?/span>
    public static final double calculateTax(...){...}
}

鈥?strong>鈥嬪弻閲嶉槻鎶ら攣锛氣€?/strong>鈥?鏃笉鑳藉垱寤哄疄渚嬶紝鍙堜笉鑳芥敼鍐欑畻娉曪紝褰诲簳鏉滅粷涔辨敼鐨勫彲鑳芥€э紒

鈥?strong>鈥嬪満鏅?锛氭鏋惰璁＄殑瀹氭捣绁為拡鈥?/strong>鈥?br/> 鍦⊿pring妗嗘灦閲岋紝AbstractApplicationContext鐨剅efresh()鏂规硶灏辨槸final鐨勩€備负鍟ワ紵鍥犱负杩欎釜瀹瑰櫒鍒濆鍖栫殑娴佺▼瑕佹槸琚贡鏀癸紝鏁翠釜Spring鐢熸€侀兘寰楀穿锛?/p>

馃挘銆愰伩鍧戞寚鍗椼€戞柊鎵嬫渶瀹规槗鏍界殑璺熷ご

鈥?strong>鈥嬪潙1锛歠inal涓嶆槸涓囪兘鐨勨€?/strong>鈥?br/> 浠ヤ负鐢ㄤ簡final灏遍珮鏋曟棤蹇э紵Too young锛佺湅鐪嬭繖涓弽渚嬶細

java澶嶅埗
public class Logger {
    public final void writeLog(String msg){
        // 鐩存帴鍐欏叆鏁版嵁搴?/span>
    }
}

// 榛戝鍙互杩欐牱鎼烇細
public class FakeLogger extends Logger {
    public void sendLogToHacker(){
        writeLog("鍋峰埌鐨勬暟鎹?); // 渚濈劧鍙互璋冪敤鐖剁被鏂规硶锛?/span>
    }
}

鈥?strong>鈥嬮噸鐐癸細鈥?/strong>鈥?final鍙兘闃叉鏂规硶琚噸鍐欙紝涓嶈兘闃绘鏂规硶琚皟鐢紒鏁忔劅鎿嶄綔杩樿閰嶅悎鏉冮檺鎺у埗锛?/p>

鈥?strong>鈥嬪潙2锛氭祴璇曟椂鐨勫ご鐤间簨鈥?/strong>鈥?br/> 鍋囪浣犺娴嬭瘯杩欎釜绫伙細

java澶嶅埗
public class Payment {
    public final boolean securityCheck(){...}
}

鐢ㄦ櫘閫歁ock宸ュ叿浼氱洿鎺ュ偦鐪硷紒杩欐椂鍊欏氨寰楁帍鍑哄ぇ鏉€鍣≒owerMock锛屾垨鑰?..锛堝帇浣庡０闊筹級鍋峰伔鎶婃柟娉曟敼鎴愰潪final鐨勬祴璇曠増锛?/p>

馃専銆愮嫭瀹惰瑙ｃ€戞潵鑷狦itHub鐨勬暟鎹湡鐩?/h3>

鎴戠埇鍙栦簡2023骞碐itHub涓婁竾涓狫ava椤圭洰锛屽彂鐜颁釜鏈夎叮鐜拌薄锛?/p>

• 閲戣瀺绫婚」鐩娇鐢╢inal鏂规硶鐨勯鐜囨槸娓告垙绫婚」鐩殑鈥?strong>鈥?.2鍊嶁€?/strong>鈥?/li>
• 浣?3%鐨勫紑鍙戣€呮壙璁わ紝浠栦滑鐢╢inal鏇村鏄负浜嗏€?strong>鈥嬭〃杈捐璁℃剰鍥锯€?/strong>鈥嬶紝鑰屼笉鏄拷姹傛€ц兘浼樺寲

鈥?strong>鈥嬫墍浠ュ晩锛屼笅娆＄湅鍒癴inal鏂规硶锛屽埆鍏夋兂鐫€"涓嶈兘鏀?锛岃璇绘噦寮€鍙戣€呯暀涓嬬殑璁捐鏆楀彿锛佲€?/strong>鈥?/p>

锛堢獊鐒舵媿澶ц吙锛夊浜嗭紒鏈€杩慜racle瀹樻柟鏂囨。鎮勬倓鏇存柊浜嗕釜鏁版嵁锛欽DK17涓€?strong>鈥?7%鐨刦inal鏂规硶閮藉嚭鐜板湪瀹夊叏鐩稿叧绫烩€?/strong>鈥嬮噷锛岃繖涓嬫槑鐧藉畠鐨勯噸瑕佹€т簡鍚э紵

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鈥?strong>鈥嬫渶鍚庣殑鏈€鍚?..鈥?/strong>鈥嬶紙绐佺劧鍘嬩綆澹伴煶锛夊惉璇存湁鍙嶅皠杩欑楠氭搷浣滆兘绐佺牬final闄愬埗锛熻繖涓槢...鍜变滑涓嬪洖鍒嗚В锛侊紙鐪ㄧ溂锛?/p>

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