ʱ : java,模板变量替换 - 百度文库ϿʼĶ
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java,ģ滻
ƪһjava javaвı
һinstanceof㣨ȷһǷһࣩ if(tinstanceofstudenty){
system.out.printint(tstudenty); }
java.lang.math
java.lang.mathпõstaticУ abs()زľֵ
ceil()شڻڲС
Random()Ϊdoubleҽ0.01.0֮
Floor()Сڻڲ max()ֵеĴ min()ֵеС ƽṹѡѭת 1.ѡif-elseswitch
1 ҳ 12 ҳ
2.ѭwhiledo-whilefor 3.תbreakcontinue ġ
ͬԪɵݼ ǹ̶IJչ Դ洢ͻ ͨ±ԷʸԪ 塢ܽ
java8ֻͣbyteshortintlongbooleancharfloatdouble
javaеɻΪĸӼλϵ
javaΪһԪͶԪһԪֻһԪλ֮䡣IJֵ͡
λλԶλΪλе㣬ֵ
ϵϵڱȽֵ֮ĴСΪһ͵ֵ
ҪΪͣҲֵ
2 ҳ 12 ҳ
Ͷ
ʾʵij
Ǵضʵгȡͬγһ㻯Ĺ
ĺ:
ʵУǿеһʵ ڼУһɱʶĴ洢 ǾйͬԺΪĶij
ԶΪݺͷļϣҲΪģ壬Ϊṩ˶Ļ ߡ
ͬһж֣ͬͬIJбΪطͲͬԹɷ
طʱݲͺȷʵʵĸ ˡ캯
캯ͬ 캯з
ڴʱʼڲ״̬ š̳
extendsؼڼ̳
3 ҳ 12 ҳ
ûextendsĬϸΪobjectֻһ࣬е̳
̳иȫԱ super
superͨʽøĹ캯ʱijԱǵĸԱ
super()캯еĵһִ ʮľ̬Ա
еľ̬࣬ijضĶ ̬
ľֻ̬ܷľ̬Ա ̬ûthis
̬ܱΪǾ̬ ̬
̬ڸ౻ʱִһ ֻܳʼľ̬ݳԱ ʮһFinalؼ
Ϊfinalܱ̳
ʹfinalؼֵķDzܱǵ һΪfinal࣬ôзΪʽfinal
4 ҳ 12 ҳ