1 /*
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 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
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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
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22  */
23 
24 /*
25  * @test
26  * @modules jdk.incubator.code
27  * @run junit TestNestedCapturingLambda
28  */
29 
30 import jdk.incubator.code.Reflect;
31 import jdk.incubator.code.CodeTransformer;
32 import jdk.incubator.code.Op;
33 import jdk.incubator.code.bytecode.BytecodeGenerator;
34 import jdk.incubator.code.dialect.core.CoreOp;
35 import org.junit.jupiter.api.Assertions;
36 import org.junit.jupiter.api.Test;
37 
38 import java.lang.invoke.MethodHandle;
39 import java.lang.invoke.MethodHandles;
40 import java.lang.reflect.Method;
41 import java.util.Optional;
42 import java.util.function.IntSupplier;
43 import java.util.stream.Stream;
44 
45 public class TestNestedCapturingLambda {
46 
47     @FunctionalInterface
48     @Reflect
49     interface QIntSupplier extends IntSupplier {
50     }
51 
52     @Reflect
53     static public int f(int a) {
54         if (a > 0) {
55             QIntSupplier s = () -> a;
56             test(s, a);
57             return s.getAsInt();
58         } else {
59             return 0;
60         }
61     }
62 
63     static void test(QIntSupplier s, int a) {
64         @SuppressWarnings("unchecked")
65         CoreOp.Var<Integer> capture = (CoreOp.Var<Integer>) Op.ofQuotable(s).get().capturedValues().values().iterator().next();
66         Assertions.assertEquals(a, capture.value().intValue());
67     }
68 
69     @Test
70     public void testf() throws Throwable {
71         CoreOp.FuncOp f = getFuncOp("f");
72 
73         MethodHandle mh = generate(f);
74 
75         Assertions.assertEquals(f(42), (int) mh.invoke(42));
76         Assertions.assertEquals(f(-1), (int) mh.invoke(-1));
77     }
78 
79     static MethodHandle generate(CoreOp.FuncOp f) {
80         System.out.println(f.toText());
81 
82         CoreOp.FuncOp lf = f.transform(CodeTransformer.LOWERING_TRANSFORMER);
83         System.out.println(lf.toText());
84 
85         return BytecodeGenerator.generate(MethodHandles.lookup(), lf);
86     }
87 
88     static CoreOp.FuncOp getFuncOp(String name) {
89         Optional<Method> om = Stream.of(TestNestedCapturingLambda.class.getDeclaredMethods())
90                 .filter(m -> m.getName().equals(name))
91                 .findFirst();
92 
93         Method m = om.get();
94         return Op.ofMethod(m).get();
95     }
96 }