data-structures/java/Dictionary/UALdictionary.java

/** Dictionary implemented by unsorted array-based list */
class UALdictionary<Key, E> implements Dictionary<Key, E> {
	private static final int defaultSize = 10;	// Default size
	private AList<KVpair<Key, E>> list;	// To store dictionary
	
	/** Constructors */
	UALdictionary() {
		this(defaultSize);
	}

	UALdictionary(int sz) {
		list = new AList<KVpair<Key, E>>(sz);
	}

	/** Reintialize */
	public void clear() {
		list.clear();
	}

	/** Insert an element: append to list */
	public void insert(Key k, E e) {
		KVpair<Key, E> temp = new KVpair<Key, E>(k , e);
		list.append(temp);
	}

	/** Use sequential search to find the element to remove */
	public E remove(Key k) {
		E temp = find(k);
		if (temp != null) list.remove();
		return temp;
	}

	/** Remove the last element */
	public E removeAny() {
		if (size != 0) {
			list.moveToEnd();
			list.prev();
			KVpair<Key, E> e = list.remove();

			return e.value();
		}
		else return null;
	}

	/** Find k using sequential search 
	 * @return Record with key value k */
	public E find(Key k) {
		for (list.moveToStart(); list.curPos() < list.length(); list.next()) {
			KVpair<Key, E> temp = list.getValue();
			if (k == temp.key()) return temp.value();
		}
		return null;	// "k" does not appear in dictionary
	}

	/** @return List size */
	public int size() {
		return list.length();
	}
}