| // Copyright 2018 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.skyframe.serialization; |
| |
| import static com.google.devtools.build.lib.skyframe.serialization.ArrayProcessor.deserializeObjectArray; |
| |
| import com.google.common.annotations.VisibleForTesting; |
| import com.google.common.collect.ImmutableList; |
| import com.google.common.collect.ImmutableMultimap; |
| import com.google.common.collect.ImmutableSet; |
| import com.google.common.collect.Iterables; |
| import com.google.common.collect.LinkedHashMultimap; |
| import com.google.common.collect.Sets; |
| import com.google.devtools.build.lib.skyframe.serialization.autocodec.SerializationConstant; |
| import com.google.protobuf.CodedInputStream; |
| import com.google.protobuf.CodedOutputStream; |
| import java.io.IOException; |
| import java.util.Collections; |
| import java.util.Set; |
| |
| /** {@link ObjectCodec} for {@link ImmutableSet} and other sets that should be immutable. */ |
| @SuppressWarnings({"rawtypes", "unchecked"}) |
| final class ImmutableSetCodec extends DeferredObjectCodec<Set> { |
| // Conversion of the types below to ImmutableSet is sound because the underlying types are hidden |
| // and only referenceable as the Set type. |
| |
| @VisibleForTesting |
| static final Class<Set> MULTIMAP_VALUE_SET_CLASS = |
| (Class<Set>) LinkedHashMultimap.create(ImmutableMultimap.of("a", "b")).get("a").getClass(); |
| |
| private static final Class<Set> SINGLETON_SET_CLASS = |
| (Class<Set>) Collections.singleton("a").getClass(); |
| |
| private static final Class<Set> SUBSET_CLASS = |
| (Class<Set>) Iterables.getOnlyElement(Sets.powerSet(ImmutableSet.of())).getClass(); |
| |
| /** |
| * Defines a reference constant for {@link Collections#emptySet}. |
| * |
| * <p>This is done here because we can't add the annotation to the JDK code. |
| */ |
| @SuppressWarnings({"EmptySet", "ConstantCaseForConstants"}) |
| @SerializationConstant |
| static final Set EMPTY_SET = Collections.emptySet(); |
| |
| @Override |
| public Class<ImmutableSet> getEncodedClass() { |
| return ImmutableSet.class; |
| } |
| |
| @Override |
| public ImmutableList<Class<? extends Set>> additionalEncodedClasses() { |
| return ImmutableList.of(MULTIMAP_VALUE_SET_CLASS, SINGLETON_SET_CLASS, SUBSET_CLASS); |
| } |
| |
| @Override |
| public void serialize(SerializationContext context, Set object, CodedOutputStream codedOut) |
| throws SerializationException, IOException { |
| codedOut.writeInt32NoTag(object.size()); |
| for (Object obj : object) { |
| context.serialize(obj, codedOut); |
| } |
| } |
| |
| @Override |
| public DeferredValue<Set> deserializeDeferred( |
| AsyncDeserializationContext context, CodedInputStream codedIn) |
| throws SerializationException, IOException { |
| int size = codedIn.readInt32(); |
| |
| ElementBuffer buffer = new ElementBuffer(size); |
| deserializeObjectArray(context, codedIn, buffer.elements, size); |
| return buffer; |
| } |
| |
| private static class ElementBuffer implements DeferredValue<Set> { |
| private final Object[] elements; |
| |
| private ElementBuffer(int size) { |
| this.elements = new Object[size]; |
| } |
| |
| @Override |
| public ImmutableSet call() { |
| return ImmutableSet.builderWithExpectedSize(elements.length).add(elements).build(); |
| } |
| } |
| } |