1 /*
2 * Copyright (c) 2013, 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 java.io.ByteArrayOutputStream;
25 import java.io.IOException;
26 import java.nio.file.Files;
27 import java.nio.file.Path;
28 import java.nio.file.Paths;
29 import java.util.concurrent.atomic.AtomicInteger;
30
31 /* @test
32 * @bug 8027351
33 * @summary Basic test of the finalize method
34 */
35
36 public class FinalizeOverride {
37 // finalizedCount is incremented when the finalize method is invoked
38 private static AtomicInteger finalizedCount = new AtomicInteger();
39
40 // finalizedSum and privateFinalizedInvoke are used to verify
41 // the right overrided finalize method is invoked
42 private static AtomicInteger finalizedSum = new AtomicInteger();
43 private static volatile boolean privateFinalizeInvoked = false;
44
45 public static void main(String[] argvs) throws IOException {
46 patchPrivateFinalize();
47
48 test(new Base(10), 10);
49 test(new Subclass(20), 0);
50 test(new SubSubclass(30), 30);
51 test(new PublicFinalize(40), 40*100+40);
52 test(new PrivateFinalize(50), 50);
53 test(new NoOverride(60), 60);
54 }
55
56 static void test(Object o, int expected) {
57 int count = finalizedCount.get();
58 int sum = finalizedSum.get();
59 privateFinalizeInvoked = false;
60
61 // force GC and finalization
62 o = null;
63 while (finalizedCount.get() != (count+1)) {
64 System.gc();
65 System.runFinalization();
66 }
67
68 if (privateFinalizeInvoked) {
69 throw new RuntimeException("private finalize method invoked");
70 }
71 if (finalizedCount.get() != (count+1)) {
72 throw new RuntimeException("Unexpected count=" + finalizedCount +
73 " expected=" + (count+1));
74 }
75 if (finalizedSum.get() != (sum+expected)) {
76 throw new RuntimeException("Unexpected sum=" + finalizedSum +
77 " prev=" + sum + " value=" + expected);
78 }
79 }
80
81 static void patchPrivateFinalize() throws IOException {
82 // patch the private f_nal_ze method name to "finalize"
83 String testClasses = System.getProperty("test.classes", ".");
84 Path p = Paths.get(testClasses, "FinalizeOverride$PrivateFinalize.class");
85 byte[] bytes = Files.readAllBytes(p);
86 int len = "f_nal_ze".length();
87 for (int i=0; i < bytes.length-len; i++) {
88 if (bytes[i] == 'f' &&
89 bytes[i+1] == '_' &&
90 bytes[i+2] == 'n' &&
91 bytes[i+3] == 'a' &&
92 bytes[i+4] == 'l' &&
93 bytes[i+5] == '_' &&
94 bytes[i+6] == 'z' &&
95 bytes[i+7] == 'e')
96 {
97 // s%_%i%
98 bytes[i+1] = 'i';
99 bytes[i+5] = 'i';
100 break;
101 }
102 }
103 Files.write(p, bytes);
104 }
105
106 static class Base {
107 protected int value;
108 Base(int v) {
109 this.value = v;
110 }
111 int called() {
112 finalizedSum.addAndGet(value);
113 return value;
114 }
115 protected void finalize() {
116 called();
117 finalizedCount.incrementAndGet();
118 }
119 }
120 static class PublicFinalize extends Base {
121 PublicFinalize(int v) {
122 super(v);
123 }
124 public void finalize() {
125 finalizedSum.addAndGet(value * 100);
126 called();
127 finalizedCount.incrementAndGet();
128 }
129 }
130 static class Subclass extends Base {
131 Subclass(int v) {
132 super(v);
133 }
134 protected void finalize() {
135 // no value added to sum
136 finalizedCount.incrementAndGet();
137 }
138 }
139 static class SubSubclass extends Subclass {
140 SubSubclass(int v) {
141 super(v);
142 }
143 protected final void finalize() {
144 finalizedSum.addAndGet(value);
145 finalizedCount.incrementAndGet();
146 }
147 }
148 static class PrivateFinalize extends Base {
149 PrivateFinalize(int v) {
150 super(v);
151 }
152 private void f_nal_ze() {
153 // finalization catches any exception
154 privateFinalizeInvoked = true;
155 finalizedCount.incrementAndGet();
156 }
157 }
158 static class NoOverride extends PrivateFinalize {
159 NoOverride(int v) {
160 super(v);
161 }
162 }
163 }