现有: 1. import java.util.*; 2. class ForInTest { 3.static List list - new ArrayList(): 4. 5.static List getList() { return list; } 6. 7.public static void main (Strincj[] args) { 8.list.add("a"); list.add("b"); list.add("c"); 9. //insert code here 10. System.out.print (o); 11. } 12. } 第9行插入哪一项将输出abc?()
第1题:
11. public void addStrings(List list) { 12. list.add(”foo”); 13. list.add(”bar”); 14. } What must you change in this method to compile without warnings?()
第2题:
现有: 3. import java.util.*; 4. class ForInTest { 5.static List list=new ArrayList(); 6. 7.public static void main (String [] args) { 8.list. add("a"); list. add("b");list. add( "c"); 9. //insert code here 10. System.out.print (o); 11. } 12. } 哪一行插入到第9行将导致输出“abc"?()
第3题:
You are writing a JSP that includes scriptlet code to declare a List variable and initializes that variable to anArrayList object. Which two JSP code snippets can you use to import these list types?()
第4题:
public static Iterator reverse(List list) { Collections.reverse(list); return list.iterator(); } public static void main(String[] args) { List list = new ArrayList(); list.add(” 1”); list.add(”2”); list.add(”3”); for (Object obj: reverse(list)) System.out.print(obj + “,”); } What is the result?()
第5题:
现有: 1. import java.util.*; 2. 3. Class FindStuff { 4.public static void main (String[]args) { 5, //insert code here 6. c.put ("X", 123); 7. } 8. } 分别插入到第5行,哪三行允许代码编译?()
第6题:
3. import java.util.*; 4. class ForInTest { 5. static List list = new ArrayList(); 6. 7. public static void main(String [] args) { 8. list.add("a"); list.add("b"); list.add("c"); 9. //insert code here 10. System.out.print(o); 11. } 12. } 哪一行插入到第9行将导致输出“abc”?()
第7题:
现有: 3. import java.util.*; 4. class ForInTest { 5. static List list = new ArrayList(); 6. 7. public static void main(String [] args) { 8. list.add("a"); list.add("b"); list.add("c"); 9. //insert code here 10. System.out.print(o); 11. } 12. } 哪一行插入到第9行将导致输出“abc”?()
第8题:
42
0042
An exception is thrown at runtime.
Compilation fails because of an error in line 13.
Compilation fails because of an error in line 14.
第9题:
Set set = new TreeSet();
Set set = new HashSet();
Set set = new SortedSet();
List set = new SortedList();
Set set = new LinkedHashSet();
第10题:
for(char o: list)
for(Object o: getList())
for(Object o: getList();)
for(Object o: o.getList())
第11题:
add this code after line 11: list = (List
change lines 12 and 13 to: list.add
change the method signature on line 11 to: public void addStrings(List< extends String> list) {
change the method signature on line 11 to: public void addStrings(List< super String> list) {
No changes are necessary. This method compiles without warnings.
第12题:
<%! import java.util.*; %>
<%! import java.util.List;import java.util.ArrayList; %>
<%@ page import=’java.util.List’import=’java.util.ArrayList’ %>
<%@ import types=’java.util.List’types=’java.util.ArrayList’ %>
<%@ page import=’java.util.List,java.util.ArrayList’ %>
<%@ import types=’java.util.List,java.util.ArrayList’ %>
第13题:
10. interface A { void x(); } 11. class B implements A { public void x() { } public voidy() { } } 12. class C extends B { public void x() {} } And: 20. java.util.List list = new java.util.ArrayList(); 21. list.add(new B()); 22. list.add(new C()); 23. for (A a:list) { 24. a.x(); 25. a.y();; 26. } What is the result?()
第14题:
public static void search(List
第15题:
1. import java.util.*; 2. class ForInTest { 3. static List list = new ArrayList(); 4. 5. static List getList() { return list; } 6. 7. public static void main(String [] args) { 8. list.add("a"); list.add("b"); list.add("c"); 9. // insert code here 10. System.out.print(o); 11. } 12. } 第 9 行插入哪一项将输出 abc?()
第16题:
1. import java.util.*; 2. public class Example { 3. public static void main(String[] args) { 4. // insert code here 5. set.add(new integer(2)); 6. set.add(new integer(l)); 7. System.out.println(set); 8. } 9. } Which code, inserted at line 4, guarantees that this program will output [1,2]? ()
第17题:
1. import java.util.*; 2. public class Test { 3. public static void main(String[] args) { 4. List
第18题:
11. public static void append(List list) { list.add(”0042”); } 12. public static void main(String[] args) { 13. List
第19题:
String s = strings.get(0);
Iterator i1 = strings.iterator();
String[] array1 = strings.toArray();
Iterator
String[] array2 = strings.toArray(new String[1]);
Iterator
第20题:
3,2,1,
1,2,3,
Compilation fails.
The code runs with no output.
An exception is thrown at runtime.
第21题:
for(Object o : list)
for(Iterator o : list)
for(Object o : list.iterator())
for(Iterator o : list.iterator(); o.hasNext (); )
第22题:
只有s1
只有s3
只有s1和s3
只有s1和s4
第23题:
for(Object o : list)
for(Iterator o : list)
for(Object o : list.iterator())
for(Iterator o : list.iterator(); o.hasNext (); )