com.google.devtools.build.skyframe.InMemoryGraphImpl.java Source code

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Here is the source code for com.google.devtools.build.skyframe.InMemoryGraphImpl.java

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// 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.skyframe;

import com.google.common.annotations.VisibleForTesting;
import com.google.common.base.Function;
import com.google.common.base.Predicates;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.MapMaker;
import com.google.common.collect.Maps;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ConcurrentMap;
import javax.annotation.Nullable;

/**
 * An in-memory graph implementation. All operations are thread-safe with ConcurrentMap semantics.
 * Also see {@link NodeEntry}.
 *
 * <p>This class is public only for use in alternative graph implementations.
 */
public class InMemoryGraphImpl implements InMemoryGraph {

    protected final ConcurrentMap<SkyKey, InMemoryNodeEntry> nodeMap = new MapMaker().initialCapacity(1024)
            .concurrencyLevel(200).makeMap();
    private final boolean keepEdges;

    InMemoryGraphImpl() {
        this(/*keepEdges=*/ true);
    }

    public InMemoryGraphImpl(boolean keepEdges) {
        this.keepEdges = keepEdges;
    }

    @Override
    public void remove(SkyKey skyKey) {
        nodeMap.remove(skyKey);
    }

    @Override
    public InMemoryNodeEntry get(@Nullable SkyKey requestor, Reason reason, SkyKey skyKey) {
        return nodeMap.get(skyKey);
    }

    @Override
    public Map<SkyKey, NodeEntry> getBatch(SkyKey requestor, Reason reason, Iterable<SkyKey> keys) {
        // Use a HashMap, not an ImmutableMap.Builder, because we have not yet deduplicated these keys
        // and ImmutableMap.Builder does not tolerate duplicates. The map will be thrown away shortly.
        HashMap<SkyKey, NodeEntry> result = new HashMap<>();
        for (SkyKey key : keys) {
            InMemoryNodeEntry entry = get(null, Reason.OTHER, key);
            if (entry != null) {
                result.put(key, entry);
            }
        }
        return result;
    }

    protected InMemoryNodeEntry createIfAbsent(SkyKey key) {
        InMemoryNodeEntry newval = keepEdges ? new InMemoryNodeEntry() : new EdgelessInMemoryNodeEntry();
        InMemoryNodeEntry oldval = nodeMap.putIfAbsent(key, newval);
        return oldval == null ? newval : oldval;
    }

    @Override
    public Map<SkyKey, InMemoryNodeEntry> createIfAbsentBatch(@Nullable SkyKey requestor, Reason reason,
            Iterable<SkyKey> keys) {
        ImmutableMap.Builder<SkyKey, InMemoryNodeEntry> builder = ImmutableMap.builder();
        for (SkyKey key : keys) {
            builder.put(key, createIfAbsent(key));
        }
        return builder.build();
    }

    @Override
    public Map<SkyKey, SkyValue> getValues() {
        return Collections
                .unmodifiableMap(Maps.transformValues(nodeMap, new Function<InMemoryNodeEntry, SkyValue>() {
                    @Override
                    public SkyValue apply(InMemoryNodeEntry entry) {
                        return entry.toValue();
                    }
                }));
    }

    @Override
    public Map<SkyKey, SkyValue> getDoneValues() {
        return Collections.unmodifiableMap(
                Maps.filterValues(Maps.transformValues(nodeMap, new Function<InMemoryNodeEntry, SkyValue>() {
                    @Override
                    public SkyValue apply(InMemoryNodeEntry entry) {
                        return entry.isDone() ? entry.getValue() : null;
                    }
                }), Predicates.notNull()));
    }

    @Override
    public Map<SkyKey, InMemoryNodeEntry> getAllValues() {
        return Collections.unmodifiableMap(nodeMap);
    }

    @VisibleForTesting
    protected ConcurrentMap<SkyKey, ? extends NodeEntry> getNodeMap() {
        return nodeMap;
    }

    boolean keepsEdges() {
        return keepEdges;
    }

    @Override
    public Iterable<SkyKey> getCurrentlyAvailableNodes(Iterable<SkyKey> keys, Reason reason) {
        ImmutableSet.Builder<SkyKey> builder = ImmutableSet.builder();
        for (SkyKey key : keys) {
            if (get(null, reason, key) != null) {
                builder.add(key);
            }
        }
        return builder.build();
    }
}