Method getOrDefault

guava/src/com/google/common/collect/Maps.java:897–906

(@Nullable Object key, @Nullable V defaultValue)

    }

    @Override
    public @Nullable V getOrDefault(@Nullable Object key, @Nullable V defaultValue) {
      if (Collections2.safeContains(backingSet(), key)) {
        @SuppressWarnings("unchecked") // unsafe, but Javadoc warns about it
        K k = (K) key;
        return function.apply(k);
      } else {
        return defaultValue;
      }
    }

    @Override
    public @Nullable V remove(@Nullable Object key) {