gradle-master/subprojects/core/src/main/java/org/gradle/execution/plan/WorkNodeDependencyResolver.java
/*
 * Copyright 2018 the original author or authors.
 *
 * 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 org.gradle.execution.plan;

import org.gradle.api.Action;
import org.gradle.api.Task;
import org.gradle.api.internal.project.HoldsProjectState;
import org.gradle.api.internal.tasks.WorkNodeAction;
import org.gradle.internal.service.scopes.Scopes;
import org.gradle.internal.service.scopes.ServiceScope;

import java.util.IdentityHashMap;
import java.util.Map;

@ServiceScope(Scopes.Build.class)
public class WorkNodeDependencyResolver implements DependencyResolver, HoldsProjectState {
    private final Map<WorkNodeAction, ActionNode> nodesForAction = new IdentityHashMap<WorkNodeAction, ActionNode>();

    @Override
    public boolean resolve(Task task, final Object node, Action<? super Node> resolveAction) {
        if (!(node instanceof WorkNodeAction)) {
            return false;
        }

        WorkNodeAction action = (WorkNodeAction) node;
        ActionNode actionNode = actionNodeFor(action);
        resolveAction.execute(actionNode);
        return true;
    }

    @Override
    public void discardAll() {
        nodesForAction.clear();
    }

    private ActionNode actionNodeFor(WorkNodeAction action) {
        ActionNode actionNode = nodesForAction.get(action);
        if (actionNode == null) {
            actionNode = new ActionNode(action);
            nodesForAction.put(action, actionNode);
        }
        return actionNode;
    }
}
