dev.cel.runtime.MessageFactory Maven / Gradle / Ivy
// Copyright 2022 Google LLC
//
// 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
//
// https://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 dev.cel.runtime;
import com.google.common.collect.ImmutableList;
import com.google.errorprone.annotations.Immutable;
import com.google.protobuf.Message;
import dev.cel.common.internal.DefaultMessageFactory;
import dev.cel.common.internal.ProtoMessageFactory;
import java.util.Optional;
import org.jspecify.nullness.Nullable;
/**
* The {@code MessageFactory} provides a method to create a protobuf builder objects by name.
*
* @deprecated Do not use. Internally, {@link ProtoMessageFactory} should be used.
*/
@Immutable
@FunctionalInterface
@Deprecated
public interface MessageFactory {
/**
* Create a {@code Message.Builder} instance for the protobuf by {@code messageName}.
*
* Returns {@code null} if the builder could not be created.
*/
Message.@Nullable Builder newBuilder(String messageName);
/**
* Exists only to maintain FunctionalInterface requirement and to make legacy Dynamic/Linked
* message factories compatible with the new ProtoMessageFactory.
*/
default ProtoMessageFactory toProtoMessageFactory() {
return msgName -> {
Optional msgBuilder = DefaultMessageFactory.INSTANCE.newBuilder(msgName);
if (msgBuilder.isPresent()) {
return msgBuilder; // Bypass custom factory and return well known type with our own
// descriptor.
}
return Optional.ofNullable(newBuilder(msgName));
};
}
/**
* The {@code CombinedMessageFactory} takes one or more {@code MessageFactory} instances and
* attempts to create a {@code Message.Builder} instance for a given {@code messageName} by
* calling each {@code MessageFactory} in the order that they are provided to the constructor.
*/
@Immutable
final class CombinedMessageFactory implements MessageFactory {
private final ImmutableList messageFactories;
public CombinedMessageFactory(Iterable messageFactories) {
this.messageFactories = ImmutableList.copyOf(messageFactories);
}
@Override
public Message.@Nullable Builder newBuilder(String messageName) {
for (MessageFactory messageFactory : messageFactories) {
Message.Builder builder = messageFactory.newBuilder(messageName);
if (builder != null) {
return builder;
}
}
return null;
}
}
}