Filter Iterator, Java

Filter Iterator

//'main' method must be in a class 'Rextester'.
//Compiler version 1.8.0_111

import java.util.*;
import java.lang.*;

class Rextester
{  
    public static void main(String args[])
    {
        List<Integer> l = Arrays.asList(1,2,3,4,5,6,7,8,9,10);
        FilterIterator<Integer> iter = new FilterIterator<>(l.iterator(), new Filter());
        while (iter.hasNext()) System.out.println(iter.next());
    }
}

class FilterIterator<T> implements Iterator<T> {
    Iterator<T> iter;
    Filter filter;
    T nextObj;

public FilterIterator(Iterator<T> iter, Filter filter) {
        this.iter = iter;
        this.filter = filter;
        nextObj = null;
    }
    
    @Override
    public boolean hasNext() {
        while (nextObj == null && iter.hasNext()) {
            T candidate = iter.next();
            if (filter.run(candidate)) {
                nextObj = candidate;
                break;
            }
        }
        return nextObj != null;
    }
    
    @Override
    public T next() {
        hasNext();
        if (nextObj == null) throw new NoSuchElementException();
        T tmp = nextObj;
        nextObj = null;
        return tmp;
    }
}

class Filter {
    public boolean run(Object i) {
        return ((Integer) i % 3) == 0;
    }
}


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