FinallyLineNumberTest.java revision 4177:f52e81f886fb 
1/*
2 * Copyright (c) 2015, 2017, 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 8134759
27 * @summary Add LineNumberTable attribute for return bytecodes split around finally code
28 * @modules jdk.jdeps/com.sun.tools.classfile
29 */
30
31import com.sun.tools.classfile.ClassFile;
32import com.sun.tools.classfile.ConstantPoolException;
33import com.sun.tools.classfile.Method;
34import com.sun.tools.classfile.Attribute;
35import com.sun.tools.classfile.Code_attribute;
36import com.sun.tools.classfile.LineNumberTable_attribute;
37import com.sun.tools.classfile.LineNumberTable_attribute.Entry;
38
39import java.io.IOException;
40
41public class FinallyLineNumberTest {
42    public static void main(String[] args) throws Exception {
43        // check that we have 5 consecutive entries for method()
44        Entry[] lines = findEntries();
45        if (lines == null) {
46            throw new Exception("finally line number table could not be loaded");
47        }
48        if (lines.length != 5) {
49            // Help debug
50            System.err.println("LineTable error, got lines:");
51            for (Entry e : lines) {
52                System.err.println(e.line_number);
53            }
54            throw new Exception("finally line number table incorrect: length=" + lines.length + " expected length=5");
55        }
56
57        // return null line, for the load null operation
58        int current = lines[0].line_number;
59        int first = current;
60
61        // finally line
62        current = lines[1].line_number;
63        if (current != first + 2) {
64            throw new Exception("finally line number table incorrect: got=" + current + " expected=" + (first + 2));
65        }
66
67        // return null line, for the return operation
68        current = lines[2].line_number;
69        if (current != first) {
70            throw new Exception("finally line number table incorrect: got=" + current + " expected=" + first);
71        }
72
73        // for when exception is thrown
74        current = lines[3].line_number;
75        if (current != first + 2) {
76            throw new Exception("finally line number table incorrect: got=" + current + " expected=" + (first + 2));
77        }
78
79        // the '}' closing the finally block
80        current = lines[4].line_number;
81        if (current != first + 3) {
82            throw new Exception("finally line number table incorrect: got=" + current + " expected=" + (first + 3));
83        }
84    }
85
86    static Entry[] findEntries() throws IOException, ConstantPoolException {
87        ClassFile self = ClassFile.read(FinallyLineNumberTest.class.getResourceAsStream("FinallyLineNumberTest.class"));
88        for (Method m : self.methods) {
89            if ("method".equals(m.getName(self.constant_pool))) {
90                Code_attribute code_attribute = (Code_attribute)m.attributes.get(Attribute.Code);
91                for (Attribute at : code_attribute.attributes) {
92                    if (Attribute.LineNumberTable.equals(at.getName(self.constant_pool))) {
93                        return ((LineNumberTable_attribute)at).line_number_table;
94                    }
95                }
96            }
97        }
98        return null;
99    }
100
101    // This method should get LineNumberTable entries for:
102    // *) The load of the null
103    // *) The finally code for when an exception is *not* thrown
104    // *) The actual return, which should have the same line as the load of the null
105    // *) The finally code for when an exception *is* thrown, should have the same line as above finally code
106    public static String method(int field) {
107        try {
108            return null;
109        } finally {
110            field+=1; // Dummy
111        }
112    }
113}
114