Method addAll

classpath/java/util/TreeMap.java:195–199

(Collection<? extends K> collection)

    }

    public boolean addAll(Collection<? extends K> collection) {
      boolean change = false;
      for (K k: collection) if (add(k)) change = true;
      return change;
    }

    public boolean remove(Object key) {
      return set.removeAndReturn(new MyEntry(key, null)) != null;