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1. ÏÂÃæÄÄЩÊÇThreadÀàµÄ·½·¨()

A start() B run() C exit() D getPriority()

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1) java.lang.Error: ThrowableµÄ×ÓÀ࣬ÓÃÓÚ±ê¼ÇÑÏÖØ´íÎ󡣺ÏÀíµÄÓ¦ÓóÌÐò²»Ó¦¸ÃÈ¥try/catchÕâÖÖ´íÎó¡£¾ø´ó¶àÊýµÄ´íÎó¶¼ÊÇ·ÇÕý³£µÄ£¬¾Í¸ù±¾²»¸Ã³öÏֵġ£

java.lang.Exception: ThrowableµÄ×ÓÀ࣬ÓÃÓÚָʾһÖÖºÏÀíµÄ³ÌÐòÏëÈ¥catchµÄÌõ¼þ¡£¼´Ëü½ö½öÊÇÒ»ÖÖ³ÌÐòÔËÐÐÌõ¼þ£¬¶ø·ÇÑÏÖØ´íÎ󣬲¢ÇÒ¹ÄÀøÓû§³ÌÐòÈ¥catchËü¡£

2) ErrorºÍRuntimeException ¼°Æä×ÓÀ඼ÊÇδ¼ì²éµÄÒì³£(unchecked exceptions)£¬¶øËùÓÐÆäËûµÄExceptionÀ඼ÊǼì²éÁ˵ÄÒì³£(checked exceptions).

checked exceptions: ͨ³£ÊÇ´ÓÒ»¸ö¿ÉÒÔ»Ö¸´µÄ³ÌÐòÖÐÅ׳öÀ´µÄ£¬²¢ÇÒ×îºÃÄܹ»´ÓÕâÖÖÒì³£ÖÐʹÓóÌÐò»Ö¸´¡£±ÈÈçFileNotFoundException, ParseExceptionµÈ¡£¼ì²éÁ˵ÄÒì³£·¢ÉúÔÚ±àÒë½×¶Î£¬±ØÐëҪʹÓÃtry¡­catch(»òÕßthrows)·ñÔò±àÒ벻ͨ¹ý¡£

unchecked exceptions: ͨ³£ÊÇÈç¹ûÒ»ÇÐÕý³£µÄ»°±¾²»¸Ã·¢ÉúµÄÒì³££¬µ«ÊǵÄÈ··¢ÉúÁË¡£·¢ÉúÔÚÔËÐÐÆÚ£¬¾ßÓв»È·¶¨ÐÔ£¬Ö÷ÒªÊÇÓÉÓÚ³ÌÐòµÄÂß¼­ÎÊÌâËùÒýÆðµÄ¡£±ÈÈçArrayIndexOutOfBoundException, ClassCastExceptionµÈ¡£´ÓÓïÑÔ±¾ÉíµÄ½Ç¶È½²£¬³ÌÐò²»¸ÃÈ¥catchÕâÀàÒì³££¬ËäÈ»Äܹ»´ÓÖîÈçRuntimeExceptionÕâÑùµÄÒì³£ÖÐcatch²¢»Ö¸´£¬µ«ÊDz¢²»¹ÄÀøÖն˳ÌÐòÔ±Õâô×ö£¬ÒòΪÍêȫûҪ±ØÒª¡£ÒòΪÕâÀà´íÎó±¾Éí¾ÍÊÇbug£¬Ó¦¸Ã±»ÐÞ¸´£¬³öÏÖ´ËÀà´íÎóʱ³ÌÐò¾ÍÓ¦¸ÃÁ¢¼´Í£Ö¹Ö´ÐС£ Òò´Ë£¬Ãæ¶ÔErrorsºÍunchecked exceptionsÓ¦¸ÃÈóÌÐò×Ô¶¯ÖÕÖ¹Ö´ÐУ¬³ÌÐòÔ±²»¸Ã×öÖîÈçtry/catchÕâÑùµÄÊÂÇ飬¶øÊÇÓ¦¸Ã²éÃ÷Ô­Òò£¬Ð޸ĴúÂëÂß¼­¡£

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3. ÏÂÃæ³ÌÐòµÄÔËÐнá¹ûÊÇ()

String str1 = "hello";

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B. constructor±ØÐëÓëclassͬÃû£¬µ«·½·¨²»ÄÜÓëclassͬÃû

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6. ÏÂÃæ³ÌÐòµÄÔËÐнá¹û£º()

public static void main(String args[]) {

Thread t = new Thread() {

public void run() {

pong();

}

};

t.run();

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}

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System.out.print("pong");

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10. ÏÂÁÐ˵·¨ÕýÈ·µÄÊÇ()

A LinkedList¼Ì³Ð×ÔList

B AbstractSet¼Ì³Ð×ÔSet

C HashSet¼Ì³Ð×ÔAbstractSet

D WeakMap¼Ì³Ð×ÔHashMap

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