package dk.itu.oop.lecture5;

public abstract class FilterIterator implements OOPIterator {
	private OOPIterator inIterator;
	private Object nextElement;
	protected abstract boolean condition(Object obj);

	public FilterIterator(OOPIterator in){
		inIterator = in;
		findNext();
	}

	private void findNext(){
		while (inIterator.hasNext() ){
			nextElement = inIterator.next();
			if ( condition(nextElement) )
				return;
		}
		nextElement = null;
	}

	public boolean hasNext(){
		return nextElement != null;
	}

	public Object next(){
		Object returnMe = nextElement;
		findNext();
		return returnMe;
	}

	public Object nextFanzy(){
		try {
			return nextElement;
		}finally{
			findNext();
		}
	}

	public Object peek(){
		return nextElement;
	}

	public OOPIterator cloneMe(){
		try{
			FilterIterator clone =  (FilterIterator)super.clone();
			clone.inIterator = inIterator.cloneMe();
			return clone;
		}catch(CloneNotSupportedException shouldNotHappen){
			throw new Error("Object claims not to be able to clone");
		}
	}
}