/*
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 */
import java.util.*;

class Iterators {
  void hasNextOk(List<Integer> xs) {
    Iterator<Integer> i = xs.iterator();
    if (i.hasNext()) i.next();
  }

  void hasNextBad(List<Integer> xs) {
    Iterator<Integer> i = xs.iterator();
    i.next();
  }

  /** Check that errors don't bubble up the call chain. */
  void hasNextNotTooBadOk(List<Integer> xs) {
    hasNextBad(xs);
  }

  void hasNextInterproceduralBad(List<Integer> xs) {
    getSingleElementOk(xs.iterator());
  }

  void hasNextInterproceduralOk(List<Integer> xs) {
    Iterator<Integer> i = xs.iterator();
    if (i.hasNext()) {
      getSingleElementOk(i);
    }
  }

  void getSingleElementOk(Iterator<Integer> i) {
    i.next();
  }
}