| // Copyright 2014 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.packages; |
| |
| import com.google.devtools.build.lib.cmdline.PackageIdentifier; |
| import com.google.devtools.build.lib.concurrent.ThreadSafety.ThreadSafe; |
| import com.google.devtools.build.lib.vfs.Path; |
| |
| /** |
| * CachingPackageLocator implementations locate a package by its name. |
| * |
| * <p> Similar to #pkgcache.PathPackageLocator, but implementations are required |
| * to cache results and handle deleted packages. |
| * |
| * <p> This interface exists for two reasons: (1) to avoid creating a bad dependency edge from the |
| * PythonPreprocessor to lib.pkgcache ("dependency injection") and (2) to allow Skyframe to use |
| * pieces of legacy code while still updating the Skyframe node graph. |
| */ |
| public interface CachingPackageLocator { |
| |
| /** |
| * Returns path of BUILD file for specified package iff the specified package exists, null |
| * otherwise (e.g. invalid package name, no build file, or package has been deleted via |
| * --deleted_packages).. |
| * |
| * <p> The package's root directory may be computed by calling getParentFile(). |
| * |
| * <p> Instances of this interface are required to cache the results. |
| * |
| * <p> This method must be thread-safe. |
| */ |
| @ThreadSafe |
| Path getBuildFileForPackage(PackageIdentifier packageName); |
| |
| } |