gistfile1.txt

/**
 *  A class representation of a Bag type using ArrayList
 *	which implements BagInterface.
 *
 *  @author Jay Deuskar 
 */

import java.util.ArrayList;

public class ArrayListBag<T> implements BagInterface<T>{

	private ArrayList<T> bag;
	public int currentSize;

	public ArrayListBag(){
		currentSize = 0;
		bag = new ArrayList<T>();
	}

	public int getCurrentSize(){
		return bag.size();
	}

	public boolean isEmpty(){
		if (this.getCurrentSize() == 0)
			return true;
		else
			return false;
	}

	public boolean add(T newEntry){
		if (newEntry != null){
			bag.add(newEntry);
			currentSize++;
			return true;
		}
		else
			return false;
	}

	public T remove(){
		if (currentSize!=0)
		{
			int range = (int)Math.random() * currentSize;
			T objectToRemove = bag.get(range);
			bag.remove(range);
			currentSize--;
			return objectToRemove;	
		}
		else
			return null;
	}

	public boolean remove(T anEntry){
		if (bag.contains(anEntry)){
			bag.remove(anEntry);
			currentSize--;
			return true;
		}
		else
			return false;
	}

	public void clear(){
		bag.clear();
	}

	public int getFrequencyOf(T anEntry){
		int counter = 0;
		for (int i = 0; i < this.getCurrentSize(); i++){
			if (anEntry.equals(bag.get(i))){
				counter++;
			}
		}
		return counter;
	}

	public boolean contains(T anEntry){
		int counter = 0;
		for (T entry: this.toArray()){
			if (entry.equals(anEntry))
				counter++;
		}
		if (counter>0)
			return true;
		else
			return false;
	}

	public T[] toArray(){
		return (T[])bag.toArray(new Object[this.getCurrentSize()]);
	}

}