HiddenFrames.java revision 14176:8606d027b2c2 
1/*
2 * Copyright (c) 2015, 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/*
25 * @test
26 * @bug 8020968
27 * @summary Basic test for hidden frames
28 * @run main HiddenFrames
29 */
30
31import java.lang.StackWalker.Option;
32import java.lang.StackWalker.StackFrame;
33import java.lang.reflect.Method;
34import java.util.ArrayList;
35import java.util.List;
36import java.util.stream.Stream;
37
38public class HiddenFrames {
39    public static void main(String... args) throws Exception {
40        new HiddenFrames().test();
41        new HiddenFrames(Option.SHOW_REFLECT_FRAMES).test();
42        new HiddenFrames(Option.SHOW_HIDDEN_FRAMES).test();
43    }
44
45    private final Option option;
46    private final StackWalker walker;
47    private final List<StackFrame> lambdas = new ArrayList<>();
48    private final List<StackFrame> reflects = new ArrayList<>();
49
50    HiddenFrames() {
51        this.option = null;
52        this.walker = StackWalker.getInstance();
53    }
54    HiddenFrames(Option option) {
55        this.option = option;
56        this.walker = StackWalker.getInstance(option);
57    }
58
59    void test() throws Exception {
60        walk();
61        walkFromReflection();
62    }
63
64    void walk() {
65       Stream.of(0).forEach(i -> walker.walk(s ->
66       {
67           s.forEach(this::checkFrame);
68           return null;
69       }));
70
71        // only check hidden frames but not reflection frames
72        // walk is not invoked via reflection
73        if (option == null && !lambdas.isEmpty()) {
74            throw new RuntimeException("Hidden frames are shown");
75        }
76
77        if (option == Option.SHOW_HIDDEN_FRAMES && lambdas.isEmpty()) {
78            throw new RuntimeException("No hidden Lambda frame");
79        }
80    }
81
82    void walkFromReflection() throws Exception {
83        Method m = HiddenFrames.class.getDeclaredMethod("walk");
84        m.invoke(this);
85
86        if (option == null && !lambdas.isEmpty()) {
87            throw new RuntimeException("Hidden frames are shown");
88        }
89
90        if (option == Option.SHOW_HIDDEN_FRAMES && lambdas.isEmpty()) {
91            throw new RuntimeException("No hidden Lambda frame");
92        }
93
94        if (option != null && reflects.isEmpty()) {
95            throw new RuntimeException("No reflection frame");
96        }
97    }
98
99    void checkFrame(StackFrame frame) {
100        String cn = frame.getClassName();
101        if (cn.startsWith("java.lang.reflect.") || cn.startsWith("jdk.internal.reflect.")) {
102            reflects.add(frame);
103        }
104        if (cn.contains("$$Lambda$")) {
105            lambdas.add(frame);
106        }
107    }
108}
109