A.Strings=strings.get(0);
B.Iteratori1=strings.iterator();
C.String[]array1=strings.toArray();
D.Iterator
E.String[]array2=strings.toArray(newString[1]);
F.Iterator
第1题:
importjava.util.*;publicclassLetterASort{publicstaticvoidmain(String[]args){ArrayListstrings=newArrayList();strings.add(?aAaA”);strings.add(”AaA”);strings.add(?aAa”);strings.add(”AAaa”);Collections.sort(strings);for(Strings:strings){System.out.print(s+);}}}Whatistheresult?()
A.Compilationfails.
B.aAaAaAaAAaaAaA
C.AAaaAaAaAaaAaA
D.AaAAAaaaAaAaAa
E.aAaAaAaAaAAAaa
F.Anexceptionisthrownatruntime.
第2题:
A.test
B.null
C.Anexceptionisthrownatruntime.
D.Compilationfailsbecauseofanerrorinline1.
E.Compilationfailsbecauseofanerrorinline4.
F.Compilationfailsbecauseofanerrorinline5.
第3题:
5.如下Java代码,输出的运行结果是() public class Test{ public static void main(String[] args) { List<String> list = new ArrayList<String>(); list.add("str1"); list.add(2, "str2"); String s = list.get(1); System.out.println(s); } }
A.运行时出现异常
B.正确运行,输出str1
C.正确运行,输出str2
D.编译时出现异常
第4题:
importjava.util.*;
publicclassNameList{
privateListnames=newArrayList();
publicsynchronizedvoidadd(Stringname){names.add(name);}
publicsynchronizedvoidprintAll(){
for(inti=0;iSystem.out.print(names.get(i)+);
}
}
publicstaticvoidmain(String[]args){
finalNameListsl=newNameList();
for(inti=0;i<2;i++){
newThread(){
publicvoidruin(){
sl.add(”A”);
sl.add(”B”);
sl.add(”C”);
sl.printAll();
}
}.start();
}
}
}
Whichtwostatementsaretrueifthisclassiscompiledandrun?()
第5题:
5. 给定如下Java代码,可以填入横线处的代码是() public static void main(String[] args) { ________ list.addLast("001"); }
A.List list = new ArrayList();
B.List list = new List();
C.ArrayList list = new ArrayList();
D.LinkedList list = new LinkedList();