1. A method for classifying objects in a graph data stream, the graph data stream including a plurality of nodes that represent elements and edges that represent connections between the elements, and wherein an object in the data stream is a group of nodes together with the edges between those nodes, the method comprising: receiving a training stream of graph data, the training stream including a plurality of objects along with class labels that are associated with each of the objects; first determining discriminating sets of edges in the training stream for the class labels, wherein a discriminating set of edges is one that is indicative of the object that contains these edges having a given class label; receiving an incoming data stream of the graph data, wherein class labels have not yet been assigned to objects in the incoming data stream; second determining, based on the discriminating sets of edges, class labels that are associated with the objects in the incoming data stream; and outputting to an information repository object class label pairs based on the second determining, wherein the method is performed using a processor.