[Part I] (10pt) Please complete Part I on CSNS. Wait until the instructor grades it before you proceed to Part II.

[Part II] (20pt) For this exercise you are going to implement an online test application using JSP. The application reads a number of multiple-choice questions from a text file, displays the questions one at a time, and collects the answers from a user. Once the user completes all the questions, the application compares the user's solution to the standard solution and displays a score.

A sample file for a test can be downloaded here. The format of the file is as follows:

• A test file contains a number of test entries. The exact number of entries is unknown, but we do know that the entries are separated from one another by an empty line.
• A test entry consists of exactly five lines: the first line is the question, the next three lines are three possible answers, and the last line is a number 1, or 2, or 3, which indicates which answer is the correct answer.

Implement a TestEntry class which consists of at least the following methods:

• public TestEntry( String question, String choiceA, String choiceB, String choiceC, int correctAnswer )
• public String getQuestion()
• public String getChoiceA(), public String getChoiceB(), public String getChoiceC()
• public void setAnswer( int answer ) - set the answer to the question by a user
  
• public boolean isAnswerCorrect() - returns true if the user's answer matches the correct answer, or false otherwise.
  

Implement a class TestBean which consists of at least the following:

• A constructor which reads the test entries from a file, and store them in an ArrayList of TestEntry objects
• A read/write property currentTestEntryIndex of type int. This property specifies which test entry is current selected.
  
• A read-only property currentTestEntry of type TestEntry. This property is the currently selected entry.
• A write-only property answer of type int. This property can be used to set the user's answer to the currently selected test entry.
• A read-only property lastEntry of type boolean. The value of this property is true if the currently selected entry is the last entry in the test, or false otherwise.
  
• A read-only property score of type int. The score is calculated as (100 * number_of_correct_answers / number_of_questions) rounded to an integer.

Create a JSP page Test.jsp that uses a session scope TestBean. Test.jsp displays the test entries one at a time, and displays the score when the user completes the test, as shown in the sample display below. Note that you may not use scripting elements in the JSP.

Hints:

• You may use Expression Language to access the properties of a TestEntry object. For example, suppose the id of your TestBean is tb, you can access the question part of the current test entry as ${tb.currentTestEntry.question}.
• You may want to use a hidden form field for the index of the "next" entry.
  
• You may use the value of the lastEntry property to decide whether to display NEXT or FINISH.

[Post-Lab Activities] 

• Note that  although the online test does not provide a PREVIOUS button, a user can always use the Back button on a browser to go back to a previous test entry, and there's no way to prevent the user from doing that because browsers will cache the previously viewed pages. Can your application handle this case correctly? and if not, how can you fix it?
• Generalize your application so it can deal with any number of choices per test entry.
• Further generalize your application so it can handle multiple correct answers per test entry.
• What if we want to show all the questions in one page? and in that case, how do you collect the answers?