ITEC 120 2007fall ibarland, jdymacek

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lab07a
objects returning objects
which day to work; nextDay

For this lab, download an open a .jar file with test cases. (See how to get .jar files into BlueJ.)
You can use this file as the starting point for today's lab, or you can use your previous class Date, but you'll need (to paste in) a working implementation of isValid, as well as having PizzaServer and Date in the same project. You'll also want to paste in the test cases provided in the .jar file.

• Write whichDayToWork, as discussed in lecture yesterday. Note that the signature, documentation, and test cases have been provided in the above .jar file; you just have to write the implementation and make sure that the unit tests run.

  9am section: There was an error in the test cases you downloaded at 9am; see here for instructions on fixing testWhichDayToWork.

• Write a method Date nextDay().

  /** Return the day after `this`. (`this` must be a valid date.) * @return the day after `this`. The result will be valid if `this` is valid. */ Date nextDay() { return new Day(1899,12,31); // A dummy stub function. }

  Implementation hint: Create a new Date which has the same year and month as this, but its day-of-month is one bigger. (How do you create a Date which never existed before? Call the constructor!) Then, check whether that newly-constructed Date is valid. If so, return it. Otherwise, then create a new Date which has the same year as this, but its month is one bigger than this's month, and its day-of-month is...?
  (Myself, I would use an if-else-if, and would not have an if without an else.)

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©2007, Ian Barland, Radford University Last modified 2007.Oct.04 (Thu)

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