Examples with CycleException com.facebook.buck.graph.AcyclicDepthFirstPostOrderTraversal.CycleException used on opensource projects

Example 1 with CycleException

use of com.facebook.buck.graph.AcyclicDepthFirstPostOrderTraversal.CycleException in project buck by facebook.

the class TargetGraphHashing method hashTargetGraph.

/**
   * Given a {@link TargetGraph} and any number of root nodes to traverse,
   * returns a map of {@code (BuildTarget, HashCode)} pairs for all root
   * build targets and their dependencies.
   */
public ImmutableMap<BuildTarget, HashCode> hashTargetGraph() throws CycleException {
    try (SimplePerfEvent.Scope scope = SimplePerfEvent.scope(eventBus, PerfEventId.of("ShowTargetHashes"))) {
        AcyclicDepthFirstPostOrderTraversal<TargetNode<?, ?>> traversal = new AcyclicDepthFirstPostOrderTraversal<>(node -> targetGraph.getAll(node.getDeps()).iterator());
        final Map<BuildTarget, ForkJoinTask<HashCode>> buildTargetHashes = new HashMap<>();
        Queue<ForkJoinTask<HashCode>> tasksToSchedule = new ArrayDeque<>();
        // Start all the node tasks, bottom up
        for (final TargetNode<?, ?> node : traversal.traverse(roots)) {
            HashNodeTask task = new HashNodeTask(node, buildTargetHashes);
            buildTargetHashes.put(node.getBuildTarget(), task);
            tasksToSchedule.add(task);
        }
        // Execute tasks in parallel
        ForkJoinPool pool = new ForkJoinPool(numThreads);
        for (ForkJoinTask<HashCode> task : tasksToSchedule) {
            pool.execute(task);
        }
        // Wait for all scheduled tasks to complete
        return ImmutableMap.copyOf(Maps.transformEntries(buildTargetHashes, (key, value) -> value.join()));
    }
}