/guava/guava/src/com/google/common/graph/DirectedGraphConnections.java
return null.getKey( ) ;
return entry.getKey ( ) ;
@Override @CheckForNull protected N computeNext() { while (entries.hasNext()) { Entry<N, Object> entry = entries.next(); if (isSuccessor(entry.getValue())) { <extra_id_0> } } return endOfData(); } }; } else {