A JavaBeans component has the following field： 
11. private boolean enabled； 
Which two pairs of method declarations follow the JavaBeans standard for accessing this field？（）

1. public class A {  2.  3. private int counter = 0；  4...

单项选择题

1. public class A { 
2. 
3. private int counter = 0； 
4. 
5. public static int getInstanceCount（） { 
6. return counter； 
7. } 
8. 
9. public A（） { 
10. counter++； 
11. } 
12. 
13. } 
Given this code from Class B： 
25.A a1 =new A（）； 
26. A a2 =new A（）； 
27. A a3 =new A（）； 
28. System.out.printIn（A.getInstanceCount（） ）；
What is the result？（） 

A programmer is designing a class to encapsulate the in...

单项选择题

A programmer is designing a class to encapsulate the information about an inventory item. A JavaBeans component is needed to do this. The Inventoryltem class has private instance variables to store the item information： 
10. private int itemId； 
11. private String name； 
12. private String description； 
Which method signature follows the JavaBeans naming standards for modifying the itemld instance variable？（） 

A programmer needs to create a logging method that can ...

单项选择题

A programmer needs to create a logging method that can accept an arbitrary number of arguments. For example， it may be called in these ways： 
logIt（”log message 1 “）； 
logIt（”log message2”，”log message3”）； 
logIt（”log message4”， “log message5”， “log message6）； 
Which declaration satisfies this requirement？（）