1 /* 2 * Copyright 2022 Google LLC 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.google.android.libraries.mobiledatadownload.file; 17 18 import java.io.IOException; 19 20 /** 21 * Interface for opening a file. Implementation is passed an {@link OpenContext} which provides 22 * access to the backend, transforms, and other information that can be used to fulfill the open 23 * request. For example, a ProtoOpener could simply invoke {@link 24 * OpenContext#chainTransformsForRead} and pass that to the proto parser. 25 * 26 * <p>Openers also behave a little like builders in that their behavior can be parameterized. For 27 * example, if an extension registry is required, it can be set on the opener before passing to file 28 * storage. 29 */ 30 public interface Opener<T> { 31 /** Invoked to open a file. */ open(OpenContext openContext)32 T open(OpenContext openContext) throws IOException; 33 } 34