/guava/guava/src/com/google/common/graph/StandardNetwork.java
return nodeConnections.containsKey( node) ;NetworkConnections<N, E> connections = nodeConnections.get( node) ;
NetworkConnections<N, E> connections = nodeConnections.get ( node ) ;
} @Override public Set<N> successors(N node) { return nodeInvalidatableSet(checkedConnections(node).successors(), node); } final NetworkConnections<N, E> checkedConnections(N node) { <extra_id_0> if (connections == null) { checkNotNull(node); throw new IllegalArgumentException(String.format(NODE_NOT_IN_GRAPH, node)); } return connections; }