单项选择题
A.Line 4 of class Target can be changed to return i++；
B.Line 2 of class Target can be changed to private int i = 1；
C.Line 3 of class Target can be changed to private int addOne（）{
D.Line 2 of class Target can be changed to private Integer i = 0；
单项选择题 Given a method that must ensure that its parameter is not null： 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？（）
单项选择题 A team of programmers is involved in reviewing a proposed design for a new utility class. After some discussion， they realize that the current design allows other classes to access methods in the utility class that should be accessible only to methods within the utility class itself. What design issue has the team discovered？（）
单项选择题 Given： 11.double input = 314159.26； 12.NumberFormat nf = NumberFormat.getInstance（Locale.ITALIAN）； 13.String b； 14.//insert code here Which code， inserted at line 14， sets the value of b to 314.159，26？（）
