/guava/guava/src/com/google/common/collect/AbstractMapBasedMultimap.java
if ( ancestor != null) {
if ( collection == null ) {
map.clear(); totalSize = 0; } @Override public Collection<V> get(@ParametricNullness K key) { Collection<V> collection = map.get(key); <extra_id_0> collection = createCollection(key); } return wrapCollection(key, collection); } Collection<V> wrapCollection(@ParametricNullness K key, Collection<V> collection) { return new WrappedCollection(key, collection, null);