CSE331 Autumn 2011
Software Design and Implementation

Worksheet B: Due Friday December 9, 2011 at 11:29AM

This covers some other material from the second half of the quarter; it should take less time than did Worksheet A.

• You are allowed to use late days, and you are allowed to miss lecture. However, everybody who attends Friday's lecture and contributes to the grading will get 5% extra-credit on the worksheet. (Note: extra-credit will be considered during assignment of final grades only after all the base grades are assigned. That is, you can not get a lower grade in the course because you did not do any extra credit, but you may get a higher grade.)
• We will collect the graded assignments after lecture to record the grades (and the extra-credit).
• The solutions can be formatted or hand-written; regardless, they should be legible for the graders.
• Although we clearly will discuss the solutions in Friday's lecture, I will not be handing out a solution key at least until all students not in lecture turn in their assignments.

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(2 points each, 20 points total) True or false

1. A UML class diagram can be executed (just like a Java program can be executed).
2. Reducing the size of a test case is an important step in debugging.
3. A good practice is to treat all Java exceptions -- both checked and unchecked exceptions -- in the same way.
4. An advantage of implementing repOK as a method instead of as an exception is that it allows the implementer of a class to re-establish a broken representation invariant.
5. The singleton pattern and the ability to define multiplicity in UML provide the same power to a design/programmer.
6. Representation invariants would be more appropriate to apply to a UML class diagram than in a UML sequence diagram.
7. Regression testing in principle addresses the removal of tests that no longer apply to a program.
8. Regression testing in principle addresses the addition of tests for new program features.
9. Covariance/contravariance are concepts used to define the type system of a programming language.
10. At run-time, you cannot determine the precise value of a parameter of a generic class.

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(5 points) Consider the UML class diagram here of the adapter pattern. Does this diagram represent conventional call-return flow-of-control, or does it represent inversion-of-control? In one sentence, justify your answer.

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(5 points) True or false: The primary objective of design patterns is to make it easier to ensure correctness of an implementation. In one sentence, justify your answer.

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(5 points) Sketch a UML class diagram that describes the relationships among parties, tables, and the waiting list from A3 (Restaurant).

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(0 points) Without running the following Java program, figure out what it does:

public class Qu {
 public static void main(String[] args) {
 String[] str = {
"public class Qu {",
" public static void main(String[] args) {",
" String[] str = {",
" };",
" for(int i=0;i<3;i++)System.out.println(str[i]);",
" for(int i=0;i<9;i++)System.out.println((char)34+str[i]+(char)34+',');",
" for(int i=3;i<9;i++)System.out.println(str[i]);",
" }",
"}",
 };
 for(int i=0;i<3;i++)System.out.println(str[i]);
 for(int i=0;i<9;i++)System.out.println((char)34+str[i]+(char)34+',');
 for(int i=3;i<9;i++)System.out.println(str[i]);
 }
}

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