A ski rental company needs to keep track of the skis that are being rented in various cities.

Part 1. (4 points) For each Ski object, the information of interest is:

• the code (a string) that identifies the ski;
• the brand (a string);
• the minimum height (in cm) of a person for which the ski is suited (an integer);
• the maximum height (in cm) of a person for which the ski is suited (an integer).

• creation of a Ski, given its code, brand, minimum height, and maximum height;
• getCode: that returns the code of the ski;
• getBrand: that returns the brand of the ski;
• getMinHeight: that returns the minimum height of the ski;
• getMaxHeight: that returns the maximum height of the ski.

Solution: class Ski

Part 2. (16 points) For each city (identified by its name, a string), the skis available in that city are stored in a SkiPool data structure. Realize a Java class SkiPool, to represent SkiPool objects, that exports the following functionalities:

• creation of a SkiPool, given the name of the city; the created SkiPool is initially empty (i.e., it contains no skis);
• getCity: that returns the name of the city;
• newSki: that, given a Ski object, inserts it into the ski pool, if a ski object with the same code is not already present in the pool, throws an exception otherwise;
• getSki: that, given the code c of a ski, returns the ski object with code c in the ski pool, if such an object is present in the pool, null otherwise;
• removeSki: that, given the code c of a ski, eliminates from the ski pool the ski object with code c, if such an object is present in the pool, throws an exception otherwise;
• numSkis: that returns the number of skis in the pool;
• skisForHeight: that, given a positive integer h representing the height of a person, returns an array of strings containing the codes of all skis in the pool that are suitable for height h; a ski is suitable for a height h if h is between the minimum and maximum heights of the ski.

Solution: representation of the objects, skeleton of the class, class SkiPool, class SkiPoolException

Part 3. (6 points) Realize a static method brandsforHeight, client of the class SkiPool (i.e., external to such a class) that, given a SkiPool object sp, a positive integer h representing the height of a person, and the name f of a file, writes on the file f the brands of all those skis in sp that are suitable for height h. The method should handle exceptions due to input/output errors that may occur.

Solution

Additional files to test the solution: class Main, input file skis.txt

Part 4. (4 points) Discuss the types of errors that a program may contain, and give for each of them an example in terms of a (fragment) of Java program.