璇村埌 C/C++ 鐨勮祫婧愮鐞嗭紝浜轟漢閮戒細(xì)澶寸棝鍗婂ぉ銆傝嚜浠?/span> C++0x 錛堝氨鏄?/span> C++09 浜?jiǎn)锛?jí)鏍囧噯婕忓嚭椋庡０涔嬪悗錛?/span> C++ 鏍囧噯鏄惁浼?xì)寮曞叆鑷姩鍨冨湋譀炴敹鏈哄埗灏辨垚湄?fù)浜?jiǎn)浼楀?/span> C++ 鐖卞ソ鑰呰皥璁虹殑璇濋銆備絾鏄疄闄呬笂錛屽湪 C++ 鏍囧噯鐨勬帰绱笂錛屽瀮鍦懼洖鏀朵竴鐩村鍦ㄤ竴涓崄鍒嗕綆涓嬬殑鍦頒綅銆傞犳垚鍏惰繖涓澶勫鐨勫師鍥犲緢澶氾紝涔熷緢澶嶆潅銆傛垜浠潵鐪嬬湅绔欏湪 C++ 紼嬪簭鍛樼殑瑙掑害涓婄湅錛岃祫婧愮鐞嗘満鍒剁幇鍦ㄦ墍闈復(fù)鐨勫眬鍔褲?/span>
浠庣郴緇熺粨鏋勪笂鏉ヨ錛?/span> C/C++ 鏀寔 3 縐嶅唴瀛樼鐞嗘柟寮忥紝鍩轟簬鏍堢殑鑷姩綆＄悊錛屽熀浜庡爢鐨勫姩鎬佺鐞嗭紝鍜屽熀浜庡叏灞鍖虹殑闈?rùn)鎬佺鐞嗐傜敱浜?/span> RAII 鐨勭悊蹇碉紝瀵逛簬 C++ 鏉ヨ錛屽唴瀛樼鐞嗗拰鍏朵粬璧勬簮綆＄悊鏈川涓婃病鏈夊尯鍒傚洜姝ゅ浜庤祫婧愯岃█錛屼篃灝辮嚜鐒剁殑鎷ユ湁榪欐牱 3 縐嶇鐞嗘柟寮忋?/span>
棣栧厛綆瑕佺殑浠嬬粛涓涓?/span> RAII 銆?/span> RAII 鐨勫叏縐版槸 Resource Acquisition Is initialization 銆傝繖涓濇兂鐨勫熀鏈墜娉曟槸瀵逛簬涓縐嶆兂瑕佷嬌鐢ㄧ殑璧勬簮錛屼負(fù)鍏朵功鍐欎竴涓?/span> guard 綾伙紝鍦ㄨ綾葷殑鏋勯犲嚱鏁伴噷榪涜璧勬簮鐨勮姹傦紝鍦ㄦ瀽鏋勫嚱鏁伴噷榪涜璧勬簮鐨勯噴鏀俱備緥濡傚亣璁炬垜浠兂綆＄悊涓涓簰鏂ラ攣錛屽彲鑳界殑鏂瑰紡鏄細(xì)
struct
聽lock_guard
{
聽聽聽聽聽聽聽聽lock_guard()
{
lock
();}
聽聽聽聽聽聽聽聽
~
lock_guard()
{unlock();}
}
;
聽聽聽聽 姝ゅ悗錛屽榪欎釜瀵硅薄浣跨敤浠涔堝唴瀛樼鐞嗘柟寮忥紝涔熷氨絳変環(huán)浜庡榪欎釜浜掓枼閿佷嬌鐢ㄤ粈涔堝唴瀛樼鐞嗘柟寮忋?/p>
聽聽聽聽聽聽聽聽 鍊熷姪浜?/span> RAII 錛屼互鍚庢垜浠彲浠ュ彧璁ㄨ鍐呭瓨璧勬簮鐨勭鐞嗘柟寮忥紝鍏跺畠璧勬簮鐨勭鐞嗘柟寮忓彲浠ヤ嬌鐢?/span> RAII 鏉ュ悓鏍風(fēng)殑瀹炵幇銆傜幇鍦ㄦ垜浠凡緇忓緢鑷劧鐨勮幏寰椾簡(jiǎn)璧勬簮綆＄悊鐨?/span> 3 縐嶆柟寮忥細(xì)鍩轟簬鍫嗙殑鍔ㄦ佹柟寮忋佸熀浜庢爤鐨勮嚜鍔ㄦ柟寮忓拰鍏ㄥ眬銆傚煎緱涓鎻愮殑鏄紝榪?/span> 3 縐嶆柟寮忎腑姣旇緝涓嶅鏄撳嚭閿欑殑鍚庝袱縐嶅疄闄呬笂鍙互瑙ｅ喅澶ч儴鍒嗙殑璧勬簮綆＄悊闇姹傘傚洜涓虹粷澶ч儴鍒嗚祫婧愶紝閮藉睘浜庤幏鍙?/span> - 浣跨敤 - 閲婃斁鍨嬬殑錛屼緥濡傚緢澶氬悓姝ュ璞★紝鏂囦歡閿侊紝 WinGDI 閲岀殑璁稿 GDI 瀵硅薄銆傛垜浠己涔忕鐞嗙殑錛屽彧鏈夐偅浜涗竴嬈¤幏寰楋紝澶氫釜鐜鎷ユ湁錛屽茍涓斿彧鑳芥湁涓嬈￠噴鏀劇殑灝戞暟璧勬簮銆?/span>
聽聽聽聽聽聽聽聽 鍥炲埌鍐呭瓨妯″瀷鏉ョ湅錛屾湁涓鐐硅鎴戜滑鏃犳硶灝嗗唴瀛樹笌鍏跺畠璧勬簮絳夊悓錛堝弽榪囨潵錛屾妸鍏跺畠璧勬簮鍜屽唴瀛樼瓑鍚屽嵈鏄彲浠ョ殑錛夛紝閭ｅ氨鏄驚鐜紩鐢ㄣ?/span> A 鍐呭瓨鍙互鎸佹湁鎸囧悜 B 鍐呭瓨鐨勫紩鐢紝 B 鍐呭瓨涔熷彲浠ュ弽榪囨潵鎸佹湁 A 鍐呭瓨鐨勫紩鐢ㄣ傚驚鐜紩鐢ㄥ鑷村唴瀛樼鐞嗕笉鍙互鐢ㄢ滄槸鍚︽湁鎸囧悜璇ュ唴瀛樼殑寮曠敤鈥濇潵鍖哄垎涓鍧楀唴瀛樻槸鍚﹀彲浠ュ洖鏀躲備粠鑰屼撫澶變簡(jiǎn)涓涓粷浣崇殑綆＄悊鎵嬫銆備絾鏄湪娌℃湁寰幆寮曠敤鐨勫満鍚堜笅錛屾垜浠繕鏄湁闈炲父綆媧侀珮鏁堢殑綆＄悊鏂規(guī)硶鐨勩傞偅灝辨槸寮曠敤璁℃暟銆?/span>
聽聽聽聽聽聽聽聽 寮曠敤璁℃暟鏄湪娌℃湁寰幆寮曠敤鍦哄悎涓嬭繘琛屽唴瀛樼鐞嗙殑緇濅匠鎵嬫錛屽畠鍏鋒湁杞婚噺銆侀珮鏁堛佸嵆鏃躲佸彲鎺х殑浼樼偣銆傝屼笖鍦?/span> C++ 閲岋紝寮曠敤璁℃暟宸茬粡闈炲父鎴愮啛錛屽彧闇瑕佷嬌鐢?/span> boost.shared_ptr 鎴栬呭叾瀹冮潪瀹樻柟鐨勫紩鐢ㄨ鏁版寚閽堝簱灝卞彲浠ヤ簡(jiǎn)錛岃屼笖鎹?zhèn)?/span> C++09 寰堝彲鑳芥妸 boost.shared_ptr 綰沖叆鏍囧噯搴撱傚紩鐢ㄨ鏁扮殑鍘熷垯鏄紝濡傛灉涓涓璞℃病鏈夊埆鐨勬寚閽堟垨寮曠敤鏉ユ寚鍚戝畠錛岄偅涔堣繖涓璞″氨鏄彲浠ラ噴鏀劇殑銆傚叿浣撶殑鎵嬫硶鏈夊ぇ鎶婂ぇ鎶婄殑璧勬枡鍙互鏌ラ槄錛岃繖閲屽氨涓嶈緇嗚鏄庝簡(jiǎn)銆傚紩鐢ㄨ鏁伴氬父鍙互澶勭悊鍝簺鍦哄悎鐨勮祫婧愮鐞嗛棶棰樺憿錛熼鍏堬紝瀵逛簬鍗曟柟鍚戠殑璧勬簮綆＄悊錛屼篃灝辨槸澶氫釜 A 鐨勫疄浣撴嫢鏈?/span> 1 涓?/span> B 錛岀劧鑰?/span> B 騫朵笉浼?xì)鍙崢q囨潵渚濊禆浜?/span> A 錛堜緥濡傚涓璞″叡浜竴涓棩蹇楋級(jí)錛屽紩鐢ㄨ鏁版槸闈炲父鍚堥傜殑銆傚叾嬈★紝瀵逛簬鎷ユ湁 - 鍙嶄綔鐢ㄧ殑鍦哄悎錛屼篃灝辨槸 1 涓垨澶氫釜 A 鐨勫疄浣撴嫢鏈?/span> 1 涓垨澶氫釜 B 錛岃?/span> B 涔熸嫢鏈夎繖浜?/span> A 鐨勫疄浣撶殑寮曠敤錛屼絾鏄?/span> B 鐨勭敓瀛樻湡浠嶇劧鍐沖畾浜?/span> A 鐨勭敓瀛樻湡錛堜緥濡傜埗紿楀彛鎷ユ湁鑻ュ共瀛愮獥鍙ｏ紝瀛愮獥鍙ｄ篃鍏鋒湁 parent 鎸囬拡鎸囧悜鐖剁獥鍙ｏ紝浣嗘槸瀛愮獥鍙ｇ殑鐢熷瓨鏈熷喅瀹氫簬鐖剁獥鍙ｇ殑鐢熷瓨鏈燂級(jí)錛岃繖涓椂鍊?/span> A 鍙互瀵?/span> B 浣跨敤寮曠敤璁℃暟鎸囬拡錛岃?/span> B 鍙互瀵?/span> A 浣跨敤鍘熺敓鐨勬櫘閫氭寚閽堬紝鍚屾牱鐨勫彲浠ュ緢濂界殑瑙ｅ喅闂銆?/span>
聽聽聽聽聽聽聽聽 鐜板湪鎵鍓╀笅鐨勶紝灝卞彧鏈夌敓瀛樻湡鐨勫驚鐜緷璧栦簡(jiǎn)銆傚鏋?/span> AB 浜掔浉鎸佹湁瀵規(guī)柟鐨勫紩鐢紝鑰屼笖 AB 浜掔浉鐨勫瓨鍦ㄩ兘渚濊禆浜庡鏂癸紝榪欐牱寮曠敤璁℃暟灝辨棤娉曡В鍐充簡(jiǎn)銆備絾鏄鏋滀粩緇嗘兂涓涓嬪氨浼?xì)鍙戠帋图寴q欑鎯呭喌鍦?/span> C++ 閲屽嚑涔庝笉鍙兘瀛樺湪銆傜敓瀛樻湡寰幆渚濊禆鍙湁 2 縐嶅悗鏋滐紝瑕佷箞 A 鍜?/span> B 鐨勬瀽鏋勫嚱鏁伴噷浜掔浉鏋愭瀯錛堝綋鐒跺氨鎸備簡(jiǎn)錛夛紝瑕佷箞浜掔浉閮戒笉鏋愭瀯錛堝綋鐒跺氨娉勯湶浜?jiǎn)锛?jí)銆傝岃繖涓ょ閮芥槸鍦ㄦ甯哥紪紼嬩腑涓嶄細(xì)鍑虹幇鐨勬儏鍐點(diǎn)傛墍浠ュ鏋滃嵆浣夸粎浠呬嬌鐢ㄥ紩鐢ㄨ鏁幫紝鎴戜滑涔熷彲浠ヨВ鍐沖嚑涔庢墍鏈夌殑璧勬簮綆＄悊闂銆?/span>
鐜板湪榪樺墿涓嬮偅涔堜竴涓佺偣鏋佸皯鍑虹幇鐨勪笉鑳藉鐞嗙殑鎯呭喌錛屾垜浠彲浠ヤ嬌鐢ㄦ洿鍔犲鏉傜殑 gc 鏉ュ疄鐜般傚彲鎯滅殑鏄紝瀹炵幇涓涓?/span> gc 鎵瑕佽楄垂鐨勭簿鍔涘疄鍦ㄥお澶э紝鑰屼笖鍑犱箮涓嶅彲閬垮厤鐨勮鎴愪負(fù)渚靛叆寮忕殑搴撱傛墍浠ユ湁鐐瑰緱涓嶅伩澶便傝屼笖 gc 閫氬父浼?xì)漶旂敓鏇村鐨勬瘺鐥呭Q?/span>
1錛?/font> 聽聽聽聽聽聽聽聽聽聽聽聽聽 浣犳棤娉曞嵈鐭ュ璞℃瀽鏋勭殑鍏蜂綋鏃墮棿錛屼粠鑰屾棤娉曠湡姝ｇ煡閬撳獎(jiǎng)鍝嶇▼搴忔ц兘鐨勭摱棰堝湪浠涔堝湴鏂廣?/span>
2錛?/font> 聽聽聽聽聽聽聽聽聽聽聽聽聽 gc 閮藉懼悜浜庡ぇ閲忕殑浣跨敤鍐呭瓨錛岀洿鍒板唴瀛樹笉澶熺殑鏃跺欏啀榪涜娓呯悊錛岃繖鏍蜂細(xì)瀵艱嚧紼嬪簭鐨勫唴瀛樼敤閲忎弗閲嶉綈革紝騫朵笖浜х敓澶ч噺鐨勬崲欏點(diǎn)?/span>
3錛?/font> 聽聽聽聽聽聽聽聽聽聽聽聽聽 榪囧害鐨勪緷璧栦簬 gc 浼?xì)鋴山E嬪簭鍛樺ぇ閲忕殑鎶婂彲浠ョ敱涔嬪墠鎻愬埌鐨勫悇縐嶆柟娉曟潵澶勭悊鐨勮祫婧愪氦緇?/span> gc 鏉ュ鐞嗭紝鏃犳晠鐨勫姞閲嶄簡(jiǎn) gc 鐨勮礋鎷呫?/span>
4錛?/font> 聽聽聽聽聽聽聽聽聽聽聽聽聽 gc 鐨勭鐞嗘柟娉曞拰 C++ 鐨勬瀽鏋勫嚱鏁版湁鍙兘浜х敓璇箟涓婄殑鍐茬獊銆?/span>
榪欏氨鏄負(fù)浠涔?/span> C++ 鏍囧噯瀵瑰瀮鍦懼洖鏀剁殑鎬佸害濡傛鎭跺姡鐨勫師鍥犮?/span>
鎴戜滑鐜板湪鍥炶繃澶存潵鐪?/span> Java/C# 榪欐牱鐨勫唴緗?/span> gc 鐨勮璦銆傝繖鏍風(fēng)殑璇█鐢變簬浣跨敤浜?/span> gc 錛屽氨涓嶅彲閬垮厤鐨勬斁寮冧簡(jiǎn)鏋愭瀯鍑芥暟銆備負(fù)浠涔?/span> gc 浼?xì)鍜屾瀽鏋勫嚱鏁颁骇鐢熷啿绐佸憿锛熶竴涓?/span> gc 涓鑸細(xì)甯屾湜鍦ㄨ繘琛屽瀮鍦懼洖鏀剁殑鏃跺欙紝鏁翠釜榪囩▼鏄竴涓師瀛愮殑錛屼絾鏋愭瀯鍑芥暟浼?xì)鐮村潖杩欎竴鐐癸紝鍦ㄩ噴鏀懼唴瀛樼殑鏃跺欏鏋滆繕瑕佹墽琛屼唬鐮侊紝閭ｄ箞闅懼厤浼?xì)瀵规暣涓?/span> gc 鐜浜х敓鐮村潖鎬х殑褰卞搷銆傜敱浜庢病鏈夋瀽鏋勫嚱鏁幫紝榪欎簺璇█灝變笉鍙兘鍋氬埌 RAII 錛屼篃灝辨槸璇達(dá)紝瀹冧滑鐨?/span> gc 鎵鑳藉綆＄悊鐨勶紝涔熷氨浠呬粎鍙湁鍐呭瓨鑰屽凡浜?jiǎn)銆傚浜庡叾浠栬祫婧愶紝 Java 絳夊氨蹇呴』鎵嬪姩閲婃斁銆傝櫧鐒?/span> C# 鎻愪緵浜?/span> with 鍏抽敭瀛楁潵緙撹В榪欎竴闂錛屼絾浠嶇劧鏃犳硶褰誨簳鐨勮В鍐熾?/span>
榪樻湁浠涔堥夯鐑?chǔ)鍛㈠Q熶箣鍓嶈鐨勯偅 4 鐐瑰叏閮ㄩ兘鏈夈傝櫧鐒?/span> JVM 鐨勯熷害鍦ㄤ笉鏂殑鎻愰珮錛屼絾鏄唴瀛樹嬌鐢ㄨ繖涓鐐瑰嵈瀹屽叏娌℃湁鍙戝睍錛屼笉鑳戒笉璇存槸 gc 璇村鑷淬傚畠鎵甯︽潵浜?jiǎn)浠涔堝ソ澶勫憿錛熸槸鍐呭瓨綆＄悊鐨勮嚜鍔ㄥ寲錛岃屼笉鏄祫婧愮鐞嗙殑鑷姩鍖栥?/span>
鎵浠ヨ
C++
騫朵笉鏄笘浜烘墍鎯寵薄鐨勯偅鏍烽渶瑕?/span>
gc
錛?/span>
C++
鏈韓灝卞凡緇忔彁渚涗簡(jiǎn)瓚沖寮哄ぇ鐨勮祫婧愮鐞嗚兘鍔涖傚熀浜庢爤鐨勮嚜鍔ㄧ鐞嗭紝鎴栬呬嬌鐢ㄥ紩鐢ㄨ鏁幫紝鍑犱箮鍙互杈懼埌鍜?/span>
gc
鍚屾牱鐨勮鐩栭潰錛岃屼笖娌℃湁
gc
鐨勯偅浜涢棶棰橈紝
RAII
浣垮緱
C++
鍦ㄧ鐞嗛潪鍐呭瓨璧勬簮鐨勬椂鍊欒繕鏇村姞鏈変紭鍔匡紝涓轟粈涔堜笉浣跨敤鍛紵
ps. 璁捐涓涓潪瀹樻柟鐨?/span> gc 搴撹繕鏄彲浠ョ殑銆備絾鏄瘯绔熶笉浼?xì)鎴愪皋Z富嫻佷簡(jiǎn)銆?/span>
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