CollectorC.java

package a4;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;

import thingy.Item;

public class CollectorC implements Collector_I {
	private ArrayList<Item> input;
	
	public CollectorC() {
		input = new ArrayList<>();
	}

	@Override
	public Collection<Item> process(Item item) {
		input.add(item);
		
		HashSet<Item> testSet = new HashSet<>();
		testSet.addAll(input);
		
		if (testSet.size() >= 5) {
			for (Item i: testSet) {
				input.remove(i);
			}
			
			return testSet;
		} else {
			return null;
		}
	}

	@Override
	public void reset() {
		input.clear();
	}
}