|  | // Copyright (c) 2017, the R8 project authors. Please see the AUTHORS file | 
|  | // for details. All rights reserved. Use of this source code is governed by a | 
|  | // BSD-style license that can be found in the LICENSE file. | 
|  | package com.android.tools.r8; | 
|  |  | 
|  | import java.util.Set; | 
|  |  | 
|  | /** | 
|  | * Program resource provider for program resources of class-file kind. | 
|  | * | 
|  | * <p>Note that the classes are generally lazily requested and the corresponding class structures | 
|  | * only created on-demand when they are needed by the compiler. If never needed, the resource will | 
|  | * never be loaded. | 
|  | */ | 
|  | public interface ClassFileResourceProvider { | 
|  |  | 
|  | /** | 
|  | * Get the set of all class descriptors that can be provided. | 
|  | * | 
|  | * <p>For user program classes (eg, not class-path or library resources), this set must be | 
|  | * defined. | 
|  | * | 
|  | * @return Set of all class descriptors that can be provided or null if the set is unknown. | 
|  | */ | 
|  | Set<String> getClassDescriptors(); | 
|  |  | 
|  | /** | 
|  | * Get the program resource associated with the descriptor, or null if this provider does not have | 
|  | * a resource for the descriptor. | 
|  | * | 
|  | * <p>Method may be called several times for the same resource, and should support concurrent | 
|  | * calls from different threads. | 
|  | */ | 
|  | ProgramResource getProgramResource(String descriptor); | 
|  | } |