1 /*
2  * Copyright (C) 2008 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 com.example.android.platform_library;
18 
19 import android.util.Log;
20 
21 public final class PlatformLibrary {
22     static {
23         /*
24          * Load the library.  If it's already loaded, this does nothing.
25          */
26         System.loadLibrary("platform_library_jni");
27     }
28 
29     private int mJniInt = -1;
30 
PlatformLibrary()31     public PlatformLibrary() {}
32 
33     /*
34      * Test native methods.
35      */
getInt(boolean bad)36     public int getInt(boolean bad) {
37         /* this alters mJniInt */
38         int result = getJniInt(bad);
39 
40         /* reverse a string, for no very good reason */
41         String reverse = reverseString("Android!");
42 
43         Log.i("PlatformLibrary", "getInt: " + result + ", '" + reverse + "'");
44 
45         return mJniInt;
46     }
47 
48     /*
49      * Simple method, called from native code.
50      */
yodel(String msg)51     private static void yodel(String msg) {
52         Log.d("PlatformLibrary", "yodel: " + msg);
53     }
54 
55     /*
56      * Trivial native method call.  If "bad" is true, this will throw an
57      * exception.
58      */
getJniInt(boolean bad)59     native private int getJniInt(boolean bad);
60 
61     /*
62      * Native method that returns a new string that is the reverse of
63      * the original.  This also calls yodel().
64      */
reverseString(String str)65     native private static String reverseString(String str);
66 }
67