| // Copyright 2014 The Bazel Authors. All rights reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| package com.google.devtools.build.lib.actions; |
| |
| /** |
| * An abstract visitor for the action graph. Specializes {@link BipartiteVisitor} for artifacts and |
| * actions, and takes care of visiting the complete transitive closure. |
| */ |
| public abstract class ActionGraphVisitor extends |
| BipartiteVisitor<ActionAnalysisMetadata, Artifact> { |
| |
| private final ActionGraph actionGraph; |
| |
| public ActionGraphVisitor(ActionGraph actionGraph) { |
| this.actionGraph = actionGraph; |
| } |
| |
| /** |
| * Called for all artifacts in the visitation. Hook for subclasses. |
| * |
| * @param artifact |
| */ |
| protected void visitArtifact(Artifact artifact) {} |
| |
| /** |
| * Called for all actions in the visitation. Hook for subclasses. |
| * |
| * @param action |
| */ |
| protected void visitAction(ActionAnalysisMetadata action) {} |
| |
| /** |
| * Whether the given action should be visited. If this returns false, the visitation stops here, |
| * so the dependencies of this action are also not visited. |
| * |
| * @param action |
| */ |
| protected boolean shouldVisit(ActionAnalysisMetadata action) { |
| return true; |
| } |
| |
| /** |
| * Whether the given artifact should be visited. If this returns false, the visitation stops here, |
| * so dependencies of this artifact (if it is a generated one) are also not visited. |
| * |
| * @param artifact |
| */ |
| protected boolean shouldVisit(Artifact artifact) { |
| return true; |
| } |
| |
| @SuppressWarnings("unused") |
| protected final void visitArtifacts(Iterable<Artifact> artifacts) { |
| for (Artifact artifact : artifacts) { |
| visitArtifact(artifact); |
| } |
| } |
| |
| @Override protected void white(Artifact artifact) { |
| ActionAnalysisMetadata action = actionGraph.getGeneratingAction(artifact); |
| visitArtifact(artifact); |
| if (action != null && shouldVisit(action)) { |
| visitBlackNode(action); |
| } |
| } |
| |
| @Override protected void black(ActionAnalysisMetadata action) { |
| visitAction(action); |
| for (Artifact input : action.getInputs()) { |
| if (shouldVisit(input)) { |
| visitWhiteNode(input); |
| } |
| } |
| } |
| } |