1 /*
2  * Copyright (C) 2010 The Android Open Source Project
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 
17 package android.content.res;
18 
19 import java.io.File;
20 import java.io.IOException;
21 
22 /**
23  * Class to scan Opaque Binary Blob (OBB) files. Use this to get information
24  * about an OBB file for use in a program via {@link ObbInfo}.
25  */
26 public class ObbScanner {
27     // Don't allow others to instantiate this class
ObbScanner()28     private ObbScanner() {}
29 
30     /**
31      * Scan a file for OBB information.
32      *
33      * @param filePath path to the OBB file to be scanned.
34      * @return ObbInfo object information corresponding to the file path
35      * @throws IllegalArgumentException if the OBB file couldn't be found
36      * @throws IOException if the OBB file couldn't be read
37      */
getObbInfo(String filePath)38     public static ObbInfo getObbInfo(String filePath) throws IOException {
39         if (filePath == null) {
40             throw new IllegalArgumentException("file path cannot be null");
41         }
42 
43         final File obbFile = new File(filePath);
44         if (!obbFile.exists()) {
45             throw new IllegalArgumentException("OBB file does not exist: " + filePath);
46         }
47 
48         /*
49          * XXX This will fail to find the real canonical path if bind mounts are
50          * used, but we don't use any bind mounts right now.
51          */
52         final String canonicalFilePath = obbFile.getCanonicalPath();
53 
54         ObbInfo obbInfo = new ObbInfo();
55         obbInfo.filename = canonicalFilePath;
56         getObbInfo_native(canonicalFilePath, obbInfo);
57 
58         return obbInfo;
59     }
60 
getObbInfo_native(String filePath, ObbInfo obbInfo)61     private native static void getObbInfo_native(String filePath, ObbInfo obbInfo)
62             throws IOException;
63 }
64