1 /*
2  * Copyright (C) 2017 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 import java.lang.reflect.Method;
18 import java.lang.reflect.InvocationTargetException;
19 
20 class DebugProxy implements java.lang.reflect.InvocationHandler {
21   private Object obj;
22   static Class<?>[] interfaces = {Foo.class};
23 
newInstance(Object obj)24   public static Object newInstance(Object obj) {
25     return java.lang.reflect.Proxy.newProxyInstance(
26       Foo.class.getClassLoader(),
27       interfaces,
28       new DebugProxy(obj));
29   }
30 
DebugProxy(Object obj)31   private DebugProxy(Object obj) {
32     this.obj = obj;
33   }
34 
invoke(Object proxy, Method m, Object[] args)35   public Object invoke(Object proxy, Method m, Object[] args) throws Throwable {
36     Object result;
37     if (obj == null) {
38       return null;
39     }
40     try {
41       System.out.println("before invoking method " + m.getName());
42       result = m.invoke(obj, args);
43     } catch (InvocationTargetException e) {
44       throw e.getTargetException();
45     } catch (Exception e) {
46       throw new RuntimeException("unexpected invocation exception: " + e.getMessage());
47     } finally {
48       System.out.println("after invoking method " + m.getName());
49     }
50     return result;
51   }
52 }
53 
54 public class Main {
call(Foo foo)55   public static void call(Foo foo) {
56     if (foo == null) {
57       return;
58     }
59     foo.bar(null);
60   }
61 
main(String[] args)62   public static void main(String[] args) {
63     System.loadLibrary(args[0]);
64     Foo foo = (Foo)DebugProxy.newInstance(null);
65     ensureJitCompiled(Main.class, "call");
66     call(foo);
67   }
68 
ensureJitCompiled(Class<?> itf, String method_name)69   private static native void ensureJitCompiled(Class<?> itf, String method_name);
70 }
71