None of these objects are eligible for garbage collection.
Only the object referenced by booch is eligible for garbage collection.
Only the object referenced by snoog is eligible for garbage collection.
Only the object referenced by snooch is eligible for garbage collection.
The objects referenced by snooch and booch are eligible for garbage collection.
第1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?()
第2题:
1. public class Test { 2. public static String output =””; 3. 4. public static void foo(int i) { 5. try { 6. if(i==1) { 7. throw new Exception(); 8. } 9. output += “1”; 10. } 11. catch(Exception e) { 12. output += “2”; 13. return; 14. } 15. finally { 16. output += “3”;17. } 18. output += “4”; 19. } 20. 21. public static void main(String args[]) { 22. foo(0); 23. foo(1); 24. 25. }26. } What is the value of the variable output at line 23?()
第3题:
11.class Snoochy{12.Boochybooch;13.public Snoochy(){booch=newBoochy(this);}14.}15.16.class Boochy{17.Snoochy snooch;18.public Boochy(Snoochys){snooch=s;}19.}And the statements:21.public static void main(String[]args){22.Snoochy snoog=new Snoochy();23.snoog=null;24.//more code here25.}Which statement is true about the objects referenced by snoog,snooch,and booch immediately after line 23 executes?()
A.None of these objects are eligible for garbage collection.
B.Only the object referenced by booch is eligible for garbage collection.
C.Only the object referenced by snoog is eligible for garbage collection.
D.Only the object referenced by snooch is eligible for garbage collection.
E.The objects referenced by snooch and booch are eligible for garbage collection.
第4题:
11. class Person { 12. String name = “No name‟; 13. public Person(String nm) { name = nm; } 14. } 15. 16. class Employee extends Person { 17. String emplD = “0000”; 18. public Employee(String id) { empID = id; } 19. } 20. 21. public class EmployeeTest { 22. public static void main(String[] args) { 23. Employee e = new Employee(”4321”); 24. System.out.println(e.empID); 25. } 26. } What is the result?()
第5题:
11. class Payload { 12. private int weight; 13. public Payload(int wt) { weight = wt; } 13. public void setWeight(mt w) { weight = w; } 15. public String toString { return Integer.toString(weight); } 16. } 17. 18. public class TestPayload { 19. static void changePayload(Payload p) { 20. /* insert code here */ 21. } 22. 23. public static void main(String[] args) { 24. Payload p = new Payload(); 25. p.setWeight(1024); 26. changePayload(p); 27. System.out.println(”The value of p is “+ p); 28. } 29. } Which statement, placed at line 20, causes the code to print “The value of p is 420.”?()
第6题:
11. static class A { 12. void process() throws Exception { throw new Exception(); } 13. } 14. static class B extends A { 15. void process() { System.out.println(”B”); } 16. } 17. public static void main(String[] args) { 18. new B().process(); 19. } What is the result?()
第7题:
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?()
第8题:
1. public class GoTest { 2. public static void main(String[] args) { 3. Sente a = new Sente(); a.go(); 4. Goban b = new Goban(); b.go(); 5. Stone c = new Stone(); c.go(); 6. } 7. } 8. 9. class Sente implements Go { 10. public void go() { System.out.println(”go in Sente.”); } 11. } 12. 13. class Goban extends Sente { 14. public void go() { System.out.println(”go in Goban”); } 15. } 16. 17. class Stone extends Goban implements Go { } 18. 19. interface Go { public void go(); } What is the result?()
第9题:
11.classA { 12. public void process() { System.out.print(”A “); } } 13. class B extends A { 14. public void process() throws RuntimeException { 15. super.process(); 16. if (true) throw new RuntimeException(); 17. System.out.print(“B”); }} 18. public static void main(String[] args) { 19. try { ((A)new B()).process(); } 20. catch (Exception e) { System.out.print(”Exception “); } 21. } What is the result?()
第10题:
10. interface Foo {} 11. class Alpha implements Foo {} 12. class Beta extends Alpha {} 13. class Delta extends Beta { 14. public static void main( String[] args) { 15. Beta x = new Beta(); 16. // insert code here 17. } 18. } Which code, inserted at line 16, will cause a java.lang.ClassCastException?()