Java??????????????????????
???????????? ???????[ 2014/9/25 10:39:32 ] ????????Java ???????
???????????final??????????????????
????final???????ε????"????"?????????????????????????“????”?????“????”???????????壺??????????????????????????
???????????????
????final StringBuffer a=new StringBuffer("immutable"); final StringBuffer b=new StringBuffer("not immutable"); a=b;//?????????
?????????????????
????final StringBuffer a=new StringBuffer("immutable"); a.append(" broken!"); //???????
?????????final????????“?”(????????????????????????)??Ч??????????????????????????????????????????±????????????????????????仯??final????????????????==????????==????????????????“?”??????????????????????????????????==????????????? ???final?????к????????塣????????????????----final????????????????????????????????????????????????????У????????????????????????????????????????????????????????????????????????????????????????????????????????????final??????????“???????”??????????????
?????????壺?????????????????
??????????????????????????????????????Java??????Щ??????????
????1. ????????????????
????2. ?????????????
????3. ?????????
?????????????????Java?????????????г????????????????????????????ó??????????и???????????????????????????????????
????int??????????????0
????float??????????????0.0f
????double??????????????0.0
????boolean??????????????false
????char??????????????0(ASCII??)
????long??????????????0
???????ж?????????????????????null??????????κζ?????????鱾??????????????г????????????????????????????????null??
???????????????????????static??????instance??????????????????????instance???????????????????????static????????????????????????????????????????????????????????????ν??г????????????????????????н???????????
????????????????????????????г?????????????г?????????????????????????顣???????????????try???л?if???У????????????????????????????????????????????????????????if????????ж?????б?????????飬?????е????????????if??????ж???????????????????????????????Υ????????????????????????漲?????????else??????г???????????????????????????Σ???????????????????????У???????????δ????????????顣????try-catch????????????????try??????г?????????????????????catch??finally????У?????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????
???????????????????????????????????????????е???????????????????????????????????????????????????????????????????
????????????instanceof??????????
????instanceof??Java??????????????????==??> ?? <???????????????????????????????????Java???????????????????????????????????????????????????????boolean??????????????????
????String s = "I AM an Object!"; boolean isObject = s instanceof Object;
?????????????????String???????????????String?????????instancof??????????????????????Object???????????????????????????????true?????isObject????True??
????instanceof???Щ?????????????д??????????????????????????????????
????public class Bill {//??????} public class PhoneBill extends Bill {//??????} public class GasBill extends Bill {//??????}
????????????????????????????????Bill??????????????????????????????????????????Bill??????????????е??κ????????????instanceof???ж??
????public double calculate(Bill bill) { if (bill instanceof PhoneBill) { //????綽??? } if (bill instanceof GasBill) { //?????????? } ... }
????????????????????????????????? ?????????????????????????кú?????????????е?????????????????????÷?????????????????????????????????е?????????????????????????????????????????????????????????????????????????
????public double calculate(PhoneBill bill) { //????綽??? } public double calculate(GasBill bill) { //?????????? }
???????????????????????漰???????????????????SPASVOС??(021-61079698-8054)?????????????????????????
??????
Java???????????Щ???????????????Java????????????????Java?б???Map????????Java Web???????????????Java??????????????д?????Java????????7???????????????????????(java .net ?????)???Java??????????Python??????Java webdriver??λ????????′????е?????Java??д??????????????????Java???????????????JavaScript????????????Java?????????????????? Java???????10??????????????Java?м????????????????java???????ü???????????м???????????????????
???·???
??????????????????
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2021/9/17 15:19:29???·???????·
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2021/5/28 17:25:47??????APP??????????
2021/5/8 17:01:11????????
?????????App Bug???????????????????????Jmeter?????????QC??????APP????????????????app?????е????????jenkins+testng+ant+webdriver??????????????JMeter????HTTP???????Selenium 2.0 WebDriver ??????