单选题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?()A add this code after line 11: list = (List) list;B change lines 12 and 13 to: list.add(”foo”); list.add(”bar”);C change the method signature on line 11 to: public void addStrings(List extends String list) {D change the method signature on line 11 to: public void addStrings(List super String list) {E No changes are necessary. This method compiles without warnings.

单选题
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?()
A

 add this code after line 11: list = (List) list;

B

 change lines 12 and 13 to: list.add(”foo”); list.add(”bar”);

C

 change the method signature on line 11 to: public void addStrings(List< extends String> list) {

D

 change the method signature on line 11 to: public void addStrings(List< super String> list) {

E

 No changes are necessary. This method compiles without warnings.


参考解析

解析: 暂无解析

相关考题:

1.importjava.util.*;2.classForInTest{3.staticListlist=newArrayList();4.5.staticListgetList(){returnlist;}6.7.publicstaticvoidmain(String[]args){8.list.add(a);list.add(b);list.add(c);9.//insertcodehere10.System.out.print(o);11.}12.}第9行插入哪一项将输出abc?()A.for(charo:list)B.for(Objecto:getList())C.for(Objecto:getList();)D.for(Objecto:o.getList())

3.importjava.util.*;4.classForInTest{5.staticListlist=newArrayList();6.7.publicstaticvoidmain(String[]args){8.list.add(a);list.add(b);list.add(c);9.//insertcodehere10.System.out.print(o);11.}12.}哪一行插入到第9行将导致输出abc”?()A.for(Objecto:list)B.for(Iteratoro:list)C.for(Objecto:list.iterator())D.for(Iteratoro:list.iterator();o.hasNext();)

现有:1.importjava.util.*; 现有:1.importjava.util.*;2.classForInTest{3.staticListlist-newArrayList():4.5.staticListgetList(){returnlist;}6.7.publicstaticvoidmain(Strincj[]args){8.list.add(a);list.add(b);list.add(c);9.//insertcodehere10.System.out.print(o);11.}12.}第9行插入哪一项将输出abc?()

publicstaticvoidsearch(Listlist){list.clear();list.add(”b”);list.add(”a”);list.add(”c”);System.out.println(Collections.binarySearch(list,a”));}WhatistheresultofcallingsearchwithavalidListimplementation?()A.0B.1C.aD.bE.cF.Theresultisundefined.

publicvoidaddStrings(Listlist){12.list.add(”foo”);13.list.add(”bar”);14.}Whatmustyouchangeinthismethodtocompilewithoutwarnings?() A.addthiscodeafterline11:list=(List)list;B.changelines12and13to:list.add(”foo”);list.add(”bar”);C.changethemethodsignatureonline11to:publicvoidaddStrings(ListextendsStringlist){D.changethemethodsignatureonline11to:publicvoidaddStrings(ListsuperStringlist){E.Nochangesarenecessary.Thismethodcompileswithoutwarnings.

publicstaticIteratorreverse(Listlist){Collections.reverse(list);returnlist.iterator();}publicstaticvoidmain(String[]args){Listlist=newArrayList();list.add(”1”);list.add(”2”);list.add(”3”);for(Objectobj:reverse(list))System.out.print(obj+,”);}Whatistheresult?()A.3,2,1,B.1,2,3,C.Compilationfails.D.Thecoderunswithnooutput.E.Anexceptionisthrownatruntime.

现有:   3.import java.util.*;   4.class ForInTest {   5.static List list = new ArrayList();  6.public static void main (String [] args){   7.  8.list.add("a"); list.add("b"); list.add("c");   9.//insert code here      10.System.out.print(o);  } }   哪一行插入到第9行将导致输出“abc”?() A、 for(Object o : list)B、 for(Iterator o : list)C、 for(Object o : list.iterator())D、 for(Iterator o : list.iterator(); o.hasNext (); )

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?() A、 add this code after line 11: list = (List) list;B、 change lines 12 and 13 to: list.add(”foo”); list.add(”bar”);C、 change the method signature on line 11 to: public void addStrings(List extends String list) {D、 change the method signature on line 11 to: public void addStrings(List super String list) {E、 No changes are necessary. This method compiles without warnings.

11. List list = // more code here  12. Collections.sort(list, new MyComparator());  Which code will sort this list in the opposite order of the sort in line 12?() A、 Collections.reverseSort(list, new MyComparator());B、 Collections.sort(list, new MyComparator()); list.reverse();C、 Collections.sort(list, new InverseComparator( new MyComparator()));D、 Collections.sort(list, Collections.reverseOrder( new MyComparator()));

public static void search(List list) {  list.clear();  list.add(”b”);  list.add(”a”);  list.add(”c”);  System.out.println(Collections.binarySearch(list, “a”));  }  What is the result of calling search with a valid List implementation?()A、0B、1C、aD、bE、cF、The result is undefined.

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?() A、for(char o: list)B、for(Object o: getList())C、for(Object o: getList();)D、for(Object o: o.getList())

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?()     A、 for(char o: list)B、 for (Object o:  o.getList())C、 for(Object o: getList();)D、 for(Object o: getList())E、 for(Object o: o.getList();)

11. public class Test {  12. public void foo() {  13. assert false;  14. assert false;  15. }  16. public void bar(){  17. while(true){  18. assert false;  19. }  20. assert false;  21. }  22. }  What causes compilation to fail?()  A、 Line 13B、 Line 14C、 Line 18D、 Line 20

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?() A、 3,2,1,B、 1,2,3,C、 Compilation fails.D、 The code runs with no output.E、 An exception is thrown at runtime.

11. public static void append(List list) { list.add(”0042”); }  12. public static void main(String[] args) {  13. List intList = new ArrayList();  14. append(intList);  15. System.out.println(intList.get(0));  16. }  What is the result?() A、 42B、 0042C、 An exception is thrown at runtime.D、 Compilation fails because of an error in line 13.E、 Compilation fails because of an error in line 14.

Given:   10. class One {   11. void foo() { }   12. }   13. class Two extends One {   14. //insert method here   15. }   Which three methods, inserted individually at line 14, will correctly complete class Two?()A、 public void foo() { /* more code here */ }B、 private void foo() { /* more code here */ }C、 protected void foo() { /* more code here */ }D、 int foo() { /* more code here */ }  E、 void foo() { /* more code here */ }

单选题11. public static void append(List list) { list.add(”0042”); }  12. public static void main(String[] args) {  13. List intList = new ArrayList();  14. append(intList);  15. System.out.println(intList.get(0));  16. }  What is the result?()A 42B 0042C An exception is thrown at runtime.D Compilation fails because of an error in line 13.E Compilation fails because of an error in line 14.

单选题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?()A 3,2,1,B 1,2,3,C Compilation fails.D The code runs with no output.E An exception is thrown at runtime.

多选题Given:   10. class One {   11. void foo() { }   12. }   13. class Two extends One {   14. //insert method here   15. }   Which three methods, inserted individually at line 14, will correctly complete class Two?()Apublic void foo() { /* more code here */ }Bprivate void foo() { /* more code here */ }Cprotected void foo() { /* more code here */ }Dint foo() { /* more code here */ }Evoid foo() { /* more code here */ }

单选题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?()A add this code after line 11: list = (List) list;B change lines 12 and 13 to: list.add(”foo”); list.add(”bar”);C change the method signature on line 11 to: public void addStrings(List extends String list) {D change the method signature on line 11 to: public void addStrings(List super String list) {E No changes are necessary. This method compiles without warnings.

单选题现有:  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"?()A  for (Iterator o  :  list.iterator();  o.hasNext  ();  )B  for (Iterator 0  :  list)C  for (Object o  :  list.iterator())D  for (Object o  :  list)

单选题10. interface Foo { int bar(); }  11. public class Sprite {  12. public int fubar( Foo foo) { return foo.bar(); }  13. public void testFoo() {  14. fubar(  15. // insert code here  16.);  17. }  18. }  Which code, inserted at line 15, allows the class Sprite to compile?()A Foo { public int bar() { return 1; } }B new Foo { public int bar() { return 1; } }C newFoo() { public int bar(){return 1; } }D new class Foo { public int bar() { return 1; } }

单选题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?()A The code runs with no output.B An exception is thrown at runtime.C Compilation fails because of an error in line 20.D Compilation fails because of an error in line 21.E Compilation fails because of an error in line 23.F Compilation fails because of an error in line 25.

单选题11. List list = // more code here  12. Collections.sort(list, new MyComparator());  Which code will sort this list in the opposite order of the sort in line 12?()A Collections.reverseSort(list, new MyComparator());B Collections.sort(list, new MyComparator()); list.reverse();C Collections.sort(list, new InverseComparator( new MyComparator()));D Collections.sort(list, Collections.reverseOrder( new MyComparator()));

单选题现有:   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”?()A for(Object o : list)B for(Iterator o : list)C for(Object o : list.iterator())D for(Iterator o : list.iterator(); o.hasNext (); )

单选题现有:   3.import java.util.*;   4.class ForInTest {   5.static List list = new ArrayList();  6.public static void main (String [] args){   7.  8.list.add("a"); list.add("b"); list.add("c");   9.//insert code here      10.System.out.print(o);  } }   哪一行插入到第9行将导致输出“abc”?()A for(Object o : list)B for(Iterator o : list)C for(Object o : list.iterator())D for(Iterator o : list.iterator(); o.hasNext (); )

单选题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”?()A for(Object o : list)B for(Iterator o : list)C for(Object o : list.iterator())D for(Iterator o : list.iterator(); o.hasNext (); )

单选题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?()Afor(char o: list)Bfor(Object o: getList())Cfor(Object o: getList();)Dfor(Object o: o.getList())