public void calculate(ScheduleGraph graph) {
// forward pass
graph.getStartNode().setEarliestStartTime(0);
for (BasicEdge edge : graph.getStartNode().getConnections()) {
forward((ActionNode) edge.getTo());
}
// backward
graph.getFinishNode().setLatestStartTime(graph.getFinishNode().getEarliestStartTime());
for (BasicEdge edge : graph.getFinishNode().getBackConnections()) {
backward((ActionNode) edge.getFrom());
}
}
public void backward(ActionNode node) {
// find the min
double m = Double.POSITIVE_INFINITY;
for (BasicEdge edge : node.getConnections()) {
double d =
((ActionNode) edge.getTo()).getLatestStartTime()
- ((ActionNode) edge.getFrom()).getDuration();
m = Math.min(d, m);
}
node.setLatestStartTime(m);
// handle other nodes
for (BasicEdge edge : node.getBackConnections()) {
backward((ActionNode) edge.getFrom());
}
}
public void forward(ActionNode node) {
// find the max
double m = Double.NEGATIVE_INFINITY;
for (BasicEdge edge : node.getBackConnections()) {
double d =
((ActionNode) edge.getFrom()).getEarliestStartTime()
+ ((ActionNode) edge.getFrom()).getDuration();
m = Math.max(d, m);
}
node.setEarliestStartTime(m);
// handle other nodes
for (BasicEdge edge : node.getConnections()) {
forward((ActionNode) edge.getTo());
}
}
