1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
/*
* Copyright (c) 2024, Alphabet LLC. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* @test
* @bug 8336491
* @summary Verify that void returning expression lambdas don't box their result
* @modules jdk.compiler
* jdk.jdeps/com.sun.tools.javap
*/
import java.io.PrintWriter;
import java.io.StringWriter;
import java.nio.file.Path;
public class VoidReturnBoxing {
public static void main(String[] args) {
new VoidReturnBoxing().run();
}
void run() {
Path path = Path.of(System.getProperty("test.classes"), "T.class");
StringWriter s;
String out;
try (PrintWriter pw = new PrintWriter(s = new StringWriter())) {
com.sun.tools.javap.Main.run(new String[] {"-p", "-c", path.toString()}, pw);
out = s.toString();
}
if (out.contains("java/lang/Integer.valueOf")) {
throw new AssertionError(
"Unnecessary boxing of void returning expression lambda result:\n\n" + out);
}
}
}
class T {
int g() {
return 0;
}
Runnable r = () -> g();
}
|
