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 
31 import java.lang.invoke.MethodHandles;
32 import java.lang.reflect.InvocationHandler;
33 import java.lang.reflect.Proxy;
34 import java.net.URL;
35 import java.util.function.Function;
36 
37 /*
38  * @test
39  * @modules jdk.incubator.code
40  * @run testng TestLiftExample
41  */
42 
43 public class TestLiftExample {
44 
45     public static <T, R> Function<T, R> proxy(Function<T, R> f) {
46         @SuppressWarnings("unchecked")
47         Function<T, R> pf = (Function<T, R>) Proxy.newProxyInstance(
48                 TestLiftExample.class.getClassLoader(),
49                 new Class[]{Function.class},
50                 // @@@ Change to lambda
51                 handler(f));
52         return pf;
53     }
54 
55     static InvocationHandler handler(Function<?, ?> f) {
56         return (proxy, method, args) -> {
57             if (method.getName().equals("apply")) {
58                 int r = (int) method.invoke(f, args);
59                 return r + 1;
60             } else {
61                 return method.invoke(f, args);
62             }
63         };
64     }
65 
66     @Test
67     public void testF() throws Throwable {
68         URL resource = TestLiftExample.class.getClassLoader().getResource(TestLiftExample.class.getName().replace('.', '/') + ".class");
69         byte[] classdata = resource.openStream().readAllBytes();
70         CoreOp.FuncOp flift = BytecodeLift.lift(classdata, "proxy");
71         System.out.println(flift.toText());
72 
73         Function<Integer, Integer> f = i -> i;
74         @SuppressWarnings("unchecked")
75         Function<Integer, Integer> pf = (Function<Integer, Integer>) Interpreter.invoke(MethodHandles.lookup(),
76                 flift, f);
77 
78         Assert.assertEquals((int) pf.apply(1), 2);
79     }
80 }