| // 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 static com.google.devtools.build.lib.unsafe.UnsafeProvider.getFieldOffset; |
| import static com.google.devtools.build.lib.unsafe.UnsafeProvider.unsafe; |
| |
| import com.google.common.collect.ImmutableList; |
| import com.google.protobuf.CodedInputStream; |
| import com.google.protobuf.CodedOutputStream; |
| import java.io.IOException; |
| |
| /** |
| * An {@link AsyncObjectCodec} for {@link ImmutableList}. |
| * |
| * <p>This codec is necessary because {@link ImmutableList}: |
| * |
| * <ul> |
| * <li>has a number of hidden subclasses; and |
| * <li>marks important fields transient. |
| * </ul> |
| */ |
| @SuppressWarnings("rawtypes") // Intentional erasure of ImmutableList. |
| class ImmutableListCodec extends AsyncObjectCodec<ImmutableList> { |
| private static final Class<? extends ImmutableList> SINGLETON_IMMUTABLE_LIST_CLASS = |
| ImmutableList.<Integer>of(0).getClass(); |
| private static final Class<? extends ImmutableList> REGULAR_IMMUTABLE_LIST_CLASS = |
| ImmutableList.<Integer>of(0, 1).getClass(); |
| |
| private static final long ELEMENT_OFFSET; |
| private static final long ARRAY_OFFSET; |
| |
| static { |
| try { |
| ELEMENT_OFFSET = getFieldOffset(SINGLETON_IMMUTABLE_LIST_CLASS, "element"); |
| ARRAY_OFFSET = getFieldOffset(REGULAR_IMMUTABLE_LIST_CLASS, "array"); |
| } catch (NoSuchFieldException e) { |
| throw new ExceptionInInitializerError(e); |
| } |
| } |
| |
| @Override |
| public Class<ImmutableList> getEncodedClass() { |
| return ImmutableList.class; |
| } |
| |
| @Override |
| public void serialize( |
| SerializationContext context, ImmutableList object, CodedOutputStream codedOut) |
| throws IOException, SerializationException { |
| codedOut.writeInt32NoTag(object.size()); |
| for (Object obj : object) { |
| context.serialize(obj, codedOut); |
| } |
| } |
| |
| @Override |
| public ImmutableList deserializeAsync( |
| AsyncDeserializationContext context, CodedInputStream codedIn) |
| throws IOException, SerializationException { |
| int size = codedIn.readInt32(); |
| if (size == 0) { |
| return ImmutableList.of(); |
| } |
| |
| ImmutableList list; |
| if (size == 1) { |
| try { |
| list = (ImmutableList) unsafe().allocateInstance(SINGLETON_IMMUTABLE_LIST_CLASS); |
| } catch (InstantiationException e) { |
| throw new SerializationException( |
| "could not instantiate " + SINGLETON_IMMUTABLE_LIST_CLASS, e); |
| } |
| context.registerInitialValue(list); |
| |
| context.deserialize(codedIn, list, ELEMENT_OFFSET); |
| return list; |
| } |
| |
| try { |
| list = (ImmutableList) unsafe().allocateInstance(REGULAR_IMMUTABLE_LIST_CLASS); |
| } catch (InstantiationException e) { |
| throw new SerializationException("could not instantiate " + REGULAR_IMMUTABLE_LIST_CLASS, e); |
| } |
| context.registerInitialValue(list); |
| |
| Object[] elements = new Object[size]; |
| deserializeObjectArray(context, codedIn, elements, size); |
| |
| unsafe().putObject(list, ARRAY_OFFSET, elements); |
| |
| return list; |
| } |
| } |