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闃塊噷Java鏈€鏂扮増闈㈣瘯闆嗛敠2020 PDF 涓嬭澆
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餳嗐€丠ashMap鍜孒ashTable鐨勪笉鍚岀偣
1 緇ф壙鍜屽疄鐜扳絽寮忎笉鍚?/div>
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java.io.Serializable鎺モ紳銆?/div>
Hashtable 緇ф壙浜嶥ictionary錛屽疄鐜頒簡Map銆丆loneable銆?/div>
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2 綰跨▼瀹夊叏涓嶅悓
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3 瀵筺ull鍊肩殑澶勭悊涓嶅悓
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8 閮ㄥ垎API涓嶅悓
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涓夈€丆oncurrentHashMap涓轟粈涔堚綈HashTable鎬ц兘濂?/div>
ConcurrentHashMap 鍒嗘閿?Segment+HashEntry
HashTable绔炰簤鍚屸紑涓攣 Synchronized
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寰楀姞閿併€侾ut飩呮硶餼稿厛瀹氫綅鍒癝egment錛岀劧鍚庡湪Segment餼ヨ繘餼忔彃餳婃搷浣溿€傛彃餳婃搷浣滈渶瑕佺粡 鍘嗕袱涓楠わ紝絎紑姝ュ垽鏂槸鍚﹂渶瑕佸Segment餼ョ殑HashEntry鏁扮粍榪涒緩鎵╁錛岀餳嗘瀹氫綅娣?/div>
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錛坱hreshold錛夛紝濡傛灉瓚呰繃闃€鍊鹼紝鏁扮粍榪涒緩鎵╁銆傚€煎緱餳€鎻愮殑鏄紝Segment鐨勬墿瀹瑰垽鏂綈
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get鎿嶄綔涓嶉渶瑕侀攣銆?/div>
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鐨勫叡浜彉閲忛兘瀹氫箟鎴恦olatile銆?/div>
size()鎿嶄綔
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銆€銆€鍥犱負鍦ㄧ瘡鍔燾ount鎿嶄綔榪囩▼涓紝涔嬪墠绱姞榪囩殑count鍙戔劍鍙樺寲鐨勨紡鐜団井甯糕緝錛屾墍浠?/div>
ConcurrentHashMap鐨勫仛娉曟槸鍏堝皾璇?嬈￠€氳繃涓嶉攣浣廠egment鐨勨絽寮忔潵緇熻鍚勪釜Segment
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Segment鐨勨激餳┿€?/div>
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modCount鍙橀噺錛屽湪put , remove鍜宑lean飩呮硶餼ユ搷浣滃厓绱犲墠閮戒細灝嗗彉閲弇odCount榪涒緩鍔?/div>
1錛岄偅涔堝湪緇熻size鍓嶅悗飩愯緝modCount鏄惁鍙戔劍鍙樺寲錛屼粠飩藉緱鐭ュ鍣ㄧ殑餳も緝鏄惁鍙戔劍鍙樺寲銆?/div>
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鍥涖€丆lassLoader鐨勫垎綾誨強鍔犺澆欏哄簭
涓昏鍒?綾伙紝饣呬笅鍥炬餼婇儴鍒?/div>
JVM綾誨姞杞藉櫒錛氳繖涓ā寮忎細鍔犺澆JAVA_HOME/lib涓嬬殑jar鍖?/div>
鎵╁睍綾誨姞杞藉櫒錛氫細鍔犺澆JAVA_HOME/lib/ext涓嬬殑jar鍖?/div>
緋葷粺綾誨姞杞藉櫒錛氳繖涓細鍘誨姞杞芥寚瀹氫簡classpath鍙傛暟鎸囧畾鐨刯ar飩?浠?/div>
飩ゆ埛餼冨畾涔夌被鍔犺澆鍣細sun鎻愪緵鐨凜lassLoader鏄彲浠ヨ緇ф壙
鐨勶紝鍏佽飩ゆ埛餼冣及瀹炵幇綾誨姞杞藉櫒
綾誨姞杞藉櫒鐨勫姞杞介『搴忓鍥炬墍紺?br />
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