10. class Line { 11. public class Point { public int x,y; } 12. public Point getPoint() { return new Point(); } 13. } 14. class Triangle { 15. public Triangle() { 16. // insert code here 17. } 18. } Which code, inserted at line 16, correctly retrieves a local instance of a Point object?()
第1题:
A.Line 33 must be called within a try block.
B.The exception thrown by method1 in class A is not required to be caught.
C.The method declared on line 31 must be declared to throw a RuntimeException.
D.On line 5 of class A, the call to method2 of class B does not need to be placed in a try/catch block.
第2题:
1. public class Outer{ 2. public void someOuterMethod() { 3. // Line 3 4. } 5. public class Inner{} 6. public static void main( String[]argv ) { 7. Outer o = new Outer(); 8. // Line 8 9. } 10. } Which instantiates an instance of Inner?()
第3题:
1.public class GC{2.private Objec to;3.private void doSomethingElse(Object obj){o=obj;}4.public void doSomething(){5.Object o=new Object();6.doSomethingElse(o);7.o=new Object();8.doSomethingElse(null);9.o=null;10.}11.}When the doSomething method is called,after which line does the Object created in line 5 become available for garbage collection?()
A.Line5
B.Line6
C.Line7
D.Line8
E.Line9
F.Line10
第4题:
10. class Line { 11. public static class Point { } 12. } 13. 14. class Triangle { 15. // insert code here 16. } Which code, inserted at line 15, creates an instance of the Point class defined in Line?()
第5题:
1. public class a { 2. public void method1() { 3. try { 4. B b=new b(); 5. b.method2(); 6. // more code here 7. } catch (TestException te) { 8. throw new RuntimeException(te); 9. } 10. } 11. } 1. public class b { 2. public void method2() throws TestException { 3. // more code here 4. } 5. } 1. public class TestException extends Exception { 2. } Given: 31. public void method() { 32. A a=new a(); 33. a.method1(); 34. } Which is true if a TestException is thrown on line 3 of class b?()
第6题:
A.The application will crash.
B.The code on line 29 will be executed.
C.The code on line 5 of class A will execute.
D.The code on line 5 of class B will execute.
E.The exception will be propagated back to line 27.
第7题:
Class TestException 1. public class TestException extends Exception { 2. } Class a: 1. public class a { 2. 3. public String sayHello(String name) throws TestException { 4. 5. if(name == null) { 6. throw new TestException(); 7. } 8. 9. return “Hello “+ name; 10. } 11. 12. } A programmer wants to use this code in an application: 45. A a=new A(); 46. System.out.println(a.sayHello(”John”)); Which two are true?()
第8题:
A.Compilation will succeed for all classes and interfaces.
B.Compilation of class C will fail because of an error in line 2.
C.Compilation of class C will fail because of an error in line 6.
D.Compilation of class AImpl will fail because of an error in line 2
第9题:
1. public class A { 2. public void doit() { 3. } 4. public String doit() { 5. return “a”; 6. } 7. public double doit(int x) { 8. return 1.0; 9. } 10.} What is the result?()
第10题:
1. public class X { 2. public object m () { 3. object o = new float (3.14F); 4. object [] oa = new object [1]; 5. oa[0]= o; 6. o = null; 7. oa[0] = null; 10. return o; 9. } 10. } When is the float object created in line 3, eligible for garbage collection?()