Due

Objectives

• to use arrays to hold data
• to search arrays

Reading

Assignment

• a field that is an array of Strings to hold the words;
• a field that keeps track of how many words are in the dictionary (it will be possible that not all of the space in the array is used);
• a constructor that takes the maximum size of the dictionary as an argument, creates the array and initializes the size field;
• a method contains that takes a String as an argument and returns true if that String is somewhere in the array and false otherwise. (Do not write a method that returns from inside the loop, as on page 298)
• a method addWord that takes a String as an argument, stores that String in the array if it is not aleady present, and updates the size field (do not bother keeping the words in order and do not worry about the case in which the array is already full);
• a method equals that takes a Dictionary as an argument and returns true or false according to whether the two dictionaries are the same, where dictionaries are the same if and only if each contains all the words in the other (order does not matter).

Your class should work with the following test driver. The following code can be downloaded from the file DictionaryTest.java.

public class DictionaryTest
{
    public static void main(String[] args)
    {
        Dictionary english = new Dictionary(10);
        Dictionary german = new Dictionary(10);
        Dictionary shark = new Dictionary(2);
        Dictionary martian = new Dictionary(10);

        english.addWord("eat");
        english.addWord("five");
        english.addWord("swim");

        german.addWord("essen");
        german.addWord("funf");
        german.addWord("schwimmen");

        shark.addWord("eat");
        shark.addWord("swim");

        martian.addWord("swim");
        martian.addWord("eat");
        martian.addWord("five");

        System.out.println("=== TESTING contains ===");
        System.out.println(english.contains("two")); // should be false
        System.out.println(english.contains("funf")); // false
        System.out.println(german.contains("funf")); // true
        System.out.println(german.contains("fork".charAt(0) + "unf")); // true
	
        System.out.println("=== TESTING equals ===");
        System.out.println(english.equals(german)); // false
        System.out.println(english.equals(shark)); // false
        System.out.println(english.equals(english)); // true
        System.out.println(martian.equals(english)); // true
    }
}

Write-up

This write-up will be graded for quality of writing and use of technical terms. Sophistication of the write-up will also be accessed.

Grading

• Attendance in lab (5 pts)
• Code compiles and runs (10 pts)
• Code produces the expected output (12 pts)
• Data Fields (2 pts)
• Constructor (3 pts)
• contains (3 pts)
• addWord (4 pts)
• equals (6 pts)
• Program includes sufficient comments (5 pts)
• Write-up (50 pts)

Submissions