第1页共34页面向对象编程基础习题及答案PartI
ChoiceQuestions(1ptforeachquestion)
Toaddatobandstoreresultinb,youwrite(Note:Javaiscase-sensitive)A
b+=a;B
a=b+a;C
b=A+b;D
a+=b;2
TodeclareaconstantPI,youwriteA
finalstaticPI=3
14159;B
finalfloatPI=3
14159;C
staticdoublePI=3
14159;D
finaldoublePI=3
14159;3
Toimprovereadabilityandmaintainability,youshoulddeclare_________insteadofusingliteralvaluessuchas3
variablesB
methodsC
constantsD
classes4
Todeclareanintvariablexwithinitialvalue200,youwriteA
intx=200L;B
intx=200l;C
intx=200;D
intx=200
Toassignadoublevariabledtoanintvariablex,youwriteA
x=(long)dB
x=(int)d;C
x=(float)d;6
InJava,thewordtrueis________
aJavakeywordB
aBooleanliteralC
sameasvalue1D
sameasvalue07
WhichoftheBooleanexpressionsbelowhasincorrectsyntax
(true)&&(3>4)B
(x>0)&&(x>0)C