xref: /aosp_15_r20/art/test/2281-method-handle-invoke-static-class-unload/src-art/Main.java (revision 795d594fd825385562da6b089ea9b2033f3abf5a) 
1 /*
2  * Copyright (C) 2024 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 dalvik.system.InMemoryDexClassLoader;
18 
19 import static java.lang.invoke.MethodType.methodType;
20 
21 import java.lang.invoke.MethodHandle;
22 import java.lang.invoke.MethodHandles;
23 import java.lang.ref.WeakReference;
24 import java.lang.reflect.Constructor;
25 import java.lang.reflect.Method;
26 import java.nio.ByteBuffer;
27 import java.util.Base64;
28 import java.util.List;
29 import java.util.function.Consumer;
30 
31 public class Main {
32     // src-ex/ClassWithAMethod.java
33     private static final String DEX_FILE =
34         "ZGV4CjA0MQC4x9/g6TtIcd5240Zevdlr1D/wRBHV4Tv0BAAAeAAAAHhWNBIAAAAAAAAAADAEAAAW" +
35         "AAAAeAAAAAcAAADQAAAABAAAAOwAAAAAAAAAAAAAAAcAAAAcAQAAAQAAAFQBAAAAAAAAAAAAAPQE" +
36         "AAAAAAAAGgIAAB8CAAAnAgAAOQIAAFACAABTAgAAVgIAAGoCAACOAgAAqgIAAL4CAADfAgAA4gIA" +
37         "AOYCAAD5AgAABQMAABgDAAAeAwAAJgMAADQDAAA7AwAASAMAAAQAAAAGAAAABwAAAAgAAAAJAAAA" +
38         "CgAAAAsAAAAEAAAAAAAAAAAAAAAFAAAABQAAAAAAAAALAAAABgAAAAAAAAAMAAAABgAAABQCAAAB" +
39         "AAIAAQAAAAEAAQANAAAAAQAAABEAAAABAAEAEgAAAAEAAgAUAAAAAwADAAEAAAAEAAIAAQAAAAEA" +
40         "AAABAAAABAAAAAAAAAADAAAAGAQAAPYDAAAAAAAABAAAAAIAAAABAAAAAAAAAPwBAAACAAAAEhAP" +
41         "AAEAAAAAAAAAAAIAAAMAAAD+AAAAEQAAAAEAAAAAAAAABAIAAAUAAABxAAQAAAASABEAAAABAAEA" +
42         "AQAAAAkCAAAEAAAAcBAGAAAADgACAAAAAgAAAA0CAAAIAAAAIgADABoBFABwIAUAEAAnABoADgAs" +
43         "AA4AJwAOPAAYAA4AHgAOAAAAAAEAAAAEAAMoKUkABjxpbml0PgAQQ2xhc3NXaXRoQU1ldGhvZAAV" +
44         "Q2xhc3NXaXRoQU1ldGhvZC5qYXZhAAFJAAFMABJMQ2xhc3NXaXRoQU1ldGhvZDsAIkxhbm5vdGF0" +
45         "aW9ucy9Db25zdGFudE1ldGhvZEhhbmRsZTsAGkxqYXZhL2xhbmcvQXNzZXJ0aW9uRXJyb3I7ABJM" +
46         "amF2YS9sYW5nL09iamVjdDsAH0xqYXZhL2xhbmcvaW52b2tlL01ldGhvZEhhbmRsZTsAAVYAAlZM" +
47         "ABFjb25zdE1ldGhvZEhhbmRsZQAKZGVzY3JpcHRvcgARZmllbGRPck1ldGhvZE5hbWUABGtpbmQA" +
48         "Bm1ldGhvZAAMbWV0aG9kSGFuZGxlAAVvd25lcgALdW5yZWFjaGFibGUAnAF+fkQ4eyJiYWNrZW5k" +
49         "IjoiZGV4IiwiY29tcGlsYXRpb24tbW9kZSI6ImRlYnVnIiwiaGFzLWNoZWNrc3VtcyI6ZmFsc2Us" +
50         "Im1pbi1hcGkiOjI4LCJzaGEtMSI6IjdkZTM3N2E4MGI1MzQ1MGY1Y2ExYTNmYzUwZjZkYzk5M2U3" +
51         "ZThhM2UiLCJ2ZXJzaW9uIjoiOC44LjQtZGV2In0AAQIEDhcADxcREAQEExcCAAAFAACBgATEAwEJ" +
52         "kAMBCfwCAQqoAwEK3AMBAAAA5wMAAAAAAAAAAAAAAQAAAAAAAAADAAAAEAQAABAAAAAAAAAAAQAA" +
53         "AAAAAAABAAAAFgAAAHgAAAACAAAABwAAANAAAAADAAAABAAAAOwAAAAFAAAABwAAABwBAAAGAAAA" +
54         "AQAAAFQBAAAIAAAAAQAAAHQBAAABIAAABQAAAHwBAAADIAAABQAAAPwBAAABEAAAAQAAABQCAAAC" +
55         "IAAAFgAAABoCAAAEIAAAAQAAAOcDAAAAIAAAAQAAAPYDAAADEAAAAQAAABAEAAAGIAAAAQAAABgE" +
56         "AAAAEAAAAQAAADAEAAA=";
57 
58     private static final int ITERATIONS = 5;
59 
main(String[] args)60     public static void main(String[] args) throws Throwable {
61         verify($noinline$getJavaApiMethodHandle());
62         verify($noinline$getConstMethodHandle());
63     }
64 
verify(MethodHandle mh)65     private static void verify(MethodHandle mh) {
66         int result = 0;
67         for (int i = 0; i < ITERATIONS; ++i) {
68             try {
69                 result += (int) mh.invokeWithArguments(List.of());
70             } catch (Throwable t) {
71                 throw new RuntimeException(t);
72             }
73             Runtime.getRuntime().gc();
74             System.runFinalization();
75         }
76 
77         if (result != ITERATIONS) {
78             throw new AssertionError();
79         }
80     }
81 
$noinline$getJavaApiMethodHandle()82     private static MethodHandle $noinline$getJavaApiMethodHandle() throws Throwable {
83         ClassLoader loader = new InMemoryDexClassLoader(
84             ByteBuffer.wrap(Base64.getDecoder().decode(DEX_FILE)),
85             ClassLoader.getSystemClassLoader());
86         Class<?> clazz = loader.loadClass("ClassWithAMethod");
87         return MethodHandles.publicLookup().findStatic(clazz, "method", methodType(int.class));
88     }
89 
$noinline$getConstMethodHandle()90     private static MethodHandle $noinline$getConstMethodHandle() throws Throwable {
91         ClassLoader loader = new InMemoryDexClassLoader(
92             ByteBuffer.wrap(Base64.getDecoder().decode(DEX_FILE)),
93             ClassLoader.getSystemClassLoader());
94         Class<?> clazz = loader.loadClass("ClassWithAMethod");
95 
96         return (MethodHandle) clazz.getDeclaredMethod("constMethodHandle").invoke(null);
97     }
98 }