| // 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.android.desugar; |
| |
| import static com.google.common.base.Preconditions.checkArgument; |
| import static com.google.common.base.Preconditions.checkState; |
| |
| import com.google.common.collect.ImmutableMap; |
| import java.util.HashMap; |
| import java.util.List; |
| import java.util.Map; |
| import javax.annotation.CheckReturnValue; |
| import javax.annotation.Nullable; |
| |
| /** |
| * Opens the given list of input files and compute an index of all classes in them, to avoid |
| * scanning all inputs over and over for each class to load. An indexed inputs can have a parent |
| * that is firstly used when a file name is searched. |
| */ |
| class IndexedInputs { |
| |
| private final ImmutableMap<String, InputFileProvider> inputFiles; |
| |
| /** |
| * Parent {@link IndexedInputs} to use before to search a file name into this {@link |
| * IndexedInputs}. |
| */ |
| @Nullable |
| private final IndexedInputs parent; |
| |
| /** Index a list of input files without a parent {@link IndexedInputs}. */ |
| public IndexedInputs(List<InputFileProvider> inputProviders) { |
| this.parent = null; |
| this.inputFiles = indexInputs(inputProviders); |
| } |
| |
| /** |
| * Create a new {@link IndexedInputs} with input files previously indexed and with a parent {@link |
| * IndexedInputs}. |
| */ |
| private IndexedInputs( |
| ImmutableMap<String, InputFileProvider> inputFiles, IndexedInputs parentIndexedInputs) { |
| this.parent = parentIndexedInputs; |
| this.inputFiles = inputFiles; |
| } |
| |
| /** |
| * Create a new {@link IndexedInputs} with input files already indexed and with a parent {@link |
| * IndexedInputs}. |
| */ |
| @CheckReturnValue |
| public IndexedInputs withParent(IndexedInputs parent) { |
| checkState(this.parent == null); |
| return new IndexedInputs(this.inputFiles, parent); |
| } |
| |
| @Nullable |
| public InputFileProvider getInputFileProvider(String filename) { |
| checkArgument(filename.endsWith(".class")); |
| |
| if (parent != null) { |
| InputFileProvider inputFileProvider = parent.getInputFileProvider(filename); |
| if (inputFileProvider != null) { |
| return inputFileProvider; |
| } |
| } |
| |
| return inputFiles.get(filename); |
| } |
| |
| private ImmutableMap<String, InputFileProvider> indexInputs( |
| List<InputFileProvider> inputProviders) { |
| Map<String, InputFileProvider> indexedInputs = new HashMap<>(); |
| for (InputFileProvider inputProvider : inputProviders) { |
| for (String relativePath : inputProvider) { |
| if (relativePath.endsWith(".class") && !indexedInputs.containsKey(relativePath)) { |
| indexedInputs.put(relativePath, inputProvider); |
| } |
| } |
| } |
| return ImmutableMap.copyOf(indexedInputs); |
| } |
| } |