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.internal.downloader; 17 18 import android.net.Uri; 19 20 /** Delta file name utility class. */ 21 public class FileNameUtil { 22 23 public static final String NAME_SEPARATOR = "_"; 24 25 /** 26 * For cases that the downloaded file is different than the final file, generate a temporary file 27 * for download and name it with a suffix of the downloaded file checksum to avoid naming 28 * conflicts. 29 */ getTempFileNameWithDownloadedFileChecksum(String fileName, String checksum)30 public static String getTempFileNameWithDownloadedFileChecksum(String fileName, String checksum) { 31 return fileName + NAME_SEPARATOR + checksum; 32 } 33 34 /** Get the final file name by removing the temporary downloaded file suffix as "_checksum". */ getFinalFileUriWithTempDownloadedFile(Uri downloadedFileUri)35 public static Uri getFinalFileUriWithTempDownloadedFile(Uri downloadedFileUri) { 36 String serializedDeltaFileUri = downloadedFileUri.toString(); 37 return Uri.parse( 38 serializedDeltaFileUri.substring(0, serializedDeltaFileUri.lastIndexOf(NAME_SEPARATOR))); 39 } 40 } 41