1 /*
 2  * Copyright (c) 2024, Oracle and/or its affiliates. All rights reserved.
 3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 4  *
 5  * This code is free software; you can redistribute it and/or modify it
 6  * under the terms of the GNU General Public License version 2 only, as
 7  * published by the Free Software Foundation.
 8  *
 9  * This code is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12  * version 2 for more details (a copy is included in the LICENSE file that
13  * accompanied this code).
14  *
15  * You should have received a copy of the GNU General Public License version
16  * 2 along with this work; if not, write to the Free Software Foundation,
17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18  *
19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20  * or visit www.oracle.com if you need additional information or have any
21  * questions.
22  */
23 
24 import org.testng.Assert;
25 import org.testng.annotations.Test;
26 
27 import jdk.incubator.code.dialect.core.CoreOp;
28 import jdk.incubator.code.bytecode.BytecodeLift;
29 import jdk.incubator.code.interpreter.Interpreter;
30 import java.lang.invoke.MethodHandles;
31 import java.lang.reflect.InvocationHandler;
32 import java.lang.reflect.Proxy;
33 import java.net.URL;
34 import java.util.function.Function;
35 
36 /*
37  * @test
38  * @modules jdk.incubator.code
39  * @run testng TestLiftExample
40  */
41 
42 public class TestLiftExample {
43 
44     public static <T, R> Function<T, R> proxy(Function<T, R> f) {
45         @SuppressWarnings("unchecked")
46         Function<T, R> pf = (Function<T, R>) Proxy.newProxyInstance(
47                 TestLiftExample.class.getClassLoader(),
48                 new Class[]{Function.class},
49                 // @@@ Change to lambda
50                 handler(f));
51         return pf;
52     }
53 
54     static InvocationHandler handler(Function<?, ?> f) {
55         return (proxy, method, args) -> {
56             if (method.getName().equals("apply")) {
57                 int r = (int) method.invoke(f, args);
58                 return r + 1;
59             } else {
60                 return method.invoke(f, args);
61             }
62         };
63     }
64 
65     @Test
66     public void testF() throws Throwable {
67         URL resource = TestLiftExample.class.getClassLoader().getResource(TestLiftExample.class.getName().replace('.', '/') + ".class");
68         byte[] classdata = resource.openStream().readAllBytes();
69         CoreOp.FuncOp flift = BytecodeLift.lift(classdata, "proxy");
70         flift.writeTo(System.out);
71 
72         Function<Integer, Integer> f = i -> i;
73         @SuppressWarnings("unchecked")
74         Function<Integer, Integer> pf = (Function<Integer, Integer>) Interpreter.invoke(MethodHandles.lookup(),
75                 flift, f);
76 
77         Assert.assertEquals((int) pf.apply(1), 2);
78     }
79 }