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单选题
11. public void someMethod(Object value) {  12. // check for null value ....  20. System.out.println(value.getClass());  21. }  What, inserted at line 12, is the appropriate way to handle a null value?()
A

 assert value == null;

B

 assert value !null, “value is null”;

C

 if (value == null) { throw new AssertionException(”value is null”);

D

 if (value == null) { throw new IllegalArgumentException(”value is null”);


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考题 单选题10. public class ClassA {  11. public void methodA() {  12. ClassB classB = new ClassB();  13. classB.getValue();  14. }  15. }  And:  20. class ClassB {  21. public ClassC classC;  22.  23. public String getValue() {  24. return classC.getValue();  25. }  26. }  And:  30. class ClassC {  31. public String value;  32.  33. public String getValue() {  34. value = “ClassB”;  35. return value;  36. }  37. }  Given:  ClassA a = new ClassA();  a.methodA();  What is the result?()A  Compilation fails.B  ClassC is displayed.C  The code runs with no output.D  An exception is thrown at runtime.

考题 填空题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 24?()

考题 单选题在j2ee中,以下是firevetoablechange方法的正确的原型的是()A public void fireVetoableChange(Object  oldValue,Object newValue)B  public void fireVetoableChange(String  propertyName,Object newValue)C  public void fireVetoableChange(String  propertyName, Object  oldValue ,Object newValue)throws PropertyVetoExceptionD  public void fireVetoableChange(String  propertyName, Object  oldValue ,Object newValue)

考题 多选题11. public interface Status {  12. /* insert code here */ int MY_VALUE = 10;  13. }  Which three are valid on line 12?()AfinalBstaticCnativeDpublicEprivateFabstractGprotected