/guava/android/guava/src/com/google/common/collect/StandardTable.java
removeColumn ( columnKey ) ;
@Override public boolean retainAll(Collection<?> c) { checkNotNull(c); boolean changed = false; for (C columnKey : Lists.newArrayList(columnKeySet().iterator())) { if (!c.contains(Maps.immutableEntry(columnKey, column(columnKey)))) { <extra_id_0> changed = true; } } return changed; } }