| // Copyright 2017 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.analysis.actions; |
| |
| import com.google.devtools.build.lib.analysis.actions.AbstractFileWriteAction.DeterministicWriter; |
| import com.google.protobuf.AbstractMessageLite; |
| import com.google.protobuf.ByteString; |
| import java.io.IOException; |
| import java.io.OutputStream; |
| |
| /** A {@link DeterministicWriter} wrapping an {@link AbstractMessageLite} supplier. */ |
| public class ProtoDeterministicWriter implements DeterministicWriter { |
| private final MessageSupplier messageSupplier; |
| |
| /** Constructs a {@link ProtoDeterministicWriter} with an eagerly constructed message. */ |
| public ProtoDeterministicWriter(AbstractMessageLite<?, ?> message) { |
| this.messageSupplier = () -> message; |
| } |
| |
| /** |
| * Constructs a {@link ProtoDeterministicWriter} with the given supplier. The supplier may be |
| * called multiple times. |
| */ |
| public ProtoDeterministicWriter(MessageSupplier supplier) { |
| this.messageSupplier = supplier; |
| } |
| |
| @Override |
| public void writeOutputFile(OutputStream out) throws IOException { |
| messageSupplier.getMessage().writeTo(out); |
| } |
| |
| @Override |
| public ByteString getBytes() throws IOException { |
| return messageSupplier.getMessage().toByteString(); |
| } |
| |
| /** Supplies an {@link AbstractMessageLite}, possibly throwing {@link IOException}. */ |
| @FunctionalInterface |
| public interface MessageSupplier { |
| AbstractMessageLite<?, ?> getMessage() throws IOException; |
| } |
| } |