public boolean equals(Object o) {
if (!(o instanceof IGraph)) {
return false;
}
IGraph<Node> that = (IGraph) o;
// Note: Order of checks is important for speed.
// check if they have the same sets of nodes.
Set<Node> thisNodes = this.getNodes();
Set<Node> thatNodes = that.getNodes();
if (!thisNodes.equals(thatNodes)) {
return false;
}
// check if they have the same sets of edges.
for (Node v : thisNodes) {
Set<Node> thisPreds = this.getPreds(v);
Set<Node> thatPreds = that.getPreds(v);
if (!thisPreds.equals(thatPreds)) {
return false;
}
}
// check if they have the same sets of roots.
Set<Node> thisRoots = this.getRoots();
Set<Node> thatRoots = that.getRoots();
if (!thisRoots.equals(thatRoots)) {
return false;
}
return true;
}
