Part2-Collections-README.md

Part 2 - Collections

Section 1 - ArrayUtility

2. Ensure all the tests pass

Methods

1. Integer[] merge(Integer[] array1, Integer[] array2) - given two arrays, create a new array with elements from both array. Return the new array.
2. Integer[] rotate(Integer[] array, int number) - given an array and a number, rotate the content to the left as many times as the number given. Return the new rotated array. For example, given Integer[] array = {5, 4, 2, 18};, calling utility.rotate(array, 2); will move the first two numbers to the back so the returning array looks like this: {2, 18, 5, 4}.
3. Integer countOccurrance(Integer[] array1, Integer[] array2, Integer valueToCount) - count how many time a number appear in both arrays
4. Integer mostCommon(Integer[] array) return the element that appears in the array the most. For example, given an array {1, 5, 5, 7}, the result should be 5 because there are two fives while there are only one one and one seven.

Section 2 - ListUtility

2. Create a new class named ListUtility in src/test/java/com/zipcodewilmington/part2/
3. Make all the tests pass

Methods

1. boolean add(Integer number) - add an element to the list. Return true if it was successful. Return false otherwise
2. int size() - the number of elements that was added
3. List<Integer> getUnique() - return all the unique element in the list. For example, if you add 4, 1, 8, 3, 3, 1, 7 to the list, the method should return a new list with 4, 1, 8, 3, 7.
4. String join() - join all the elements together, separate them by a comma and space , .
5. Integer mostCommon() - return the element that appears in the list the most. For example, if you add 1, 5, 5, 7, the return value should be 5 because there are two fives while there are only one one and one seven.

Section 3 - Router

In a common web application framework, there is usually a Router class which figures out which class to call when the user goes to a certain url. The class that actually handle the user request are called the controller. In this section we will write a basic router which stores the url path and the associated controller.

2. Create a new class named Router in src/test/java/com/zipcodewilmington/part2/
3. Make all the tests pass

Methods

1. void add(String path, String controller) - given two String (a key, and a value), add the string to the map
2. int size() - the number of elements that was added
3. String getController(String path) - given a path (the key), return the controller's name (the value) associated with that path
4. void update(String path, String newController) - given a path and a new controller, associate the new controller to that path
5. void remove(String path) - remote the path from the routes
6. String toString() - List out all the path and its controller. Separate each path by a new line (\n). The format should be path -> controller.

   /user -> UserController
   /student -> StudentController