| // 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 com.google.devtools.build.lib.unsafe.UnsafeProvider; |
| import com.google.protobuf.CodedInputStream; |
| import com.google.protobuf.CodedOutputStream; |
| import java.io.IOException; |
| import java.util.EnumMap; |
| import java.util.Map; |
| import sun.misc.Unsafe; |
| |
| /** |
| * Serialize {@link EnumMap}. Subclasses of {@link EnumMap} will crash at runtime because currently |
| * there are no "benign" subclasses of {@link EnumMap} in the Bazel codebase that can be used where |
| * an {@link EnumMap} was expected. |
| */ |
| class EnumMapCodec<E extends Enum<E>, V> implements ObjectCodec<EnumMap<E, V>> { |
| // Only needed for empty EnumMaps where we can't figure out the Enum class from a sample element. |
| private final long classTypeOffset; |
| |
| EnumMapCodec() { |
| try { |
| classTypeOffset = |
| UnsafeProvider.getInstance().objectFieldOffset(EnumMap.class.getDeclaredField("keyType")); |
| } catch (NoSuchFieldException e) { |
| throw new IllegalStateException("Couldn't get keyType field fron EnumMap", e); |
| } |
| } |
| |
| @SuppressWarnings("unchecked") |
| @Override |
| public Class<EnumMap<E, V>> getEncodedClass() { |
| return (Class<EnumMap<E, V>>) (Class<?>) EnumMap.class; |
| } |
| |
| @Override |
| public void serialize(SerializationContext context, EnumMap<E, V> obj, CodedOutputStream codedOut) |
| throws SerializationException, IOException { |
| if (!obj.getClass().equals(EnumMap.class)) { |
| throw new SerializationException( |
| "Cannot serialize subclasses of EnumMap: " + obj.getClass() + " (" + obj + ")"); |
| } |
| codedOut.writeInt32NoTag(obj.size()); |
| if (obj.isEmpty()) { |
| // Do gross hack to get key type of map, since we have no concrete element to examine. |
| Unsafe unsafe = UnsafeProvider.getInstance(); |
| context.serialize(unsafe.getObject(obj, classTypeOffset), codedOut); |
| return; |
| } |
| context.serialize(obj.keySet().iterator().next().getDeclaringClass(), codedOut); |
| for (Map.Entry<E, V> entry : obj.entrySet()) { |
| codedOut.writeInt32NoTag(entry.getKey().ordinal()); |
| context.serialize(entry.getValue(), codedOut); |
| } |
| } |
| |
| @Override |
| public EnumMap<E, V> deserialize(DeserializationContext context, CodedInputStream codedIn) |
| throws SerializationException, IOException { |
| int size = codedIn.readInt32(); |
| Class<E> clazz = context.deserialize(codedIn); |
| EnumMap<E, V> result = new EnumMap<>(clazz); |
| E[] enums = clazz.getEnumConstants(); |
| for (int i = 0; i < size; i++) { |
| int ordinal = codedIn.readInt32(); |
| V val = context.deserialize(codedIn); |
| result.put(enums[ordinal], val); |
| } |
| return result; |
| } |
| } |