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 try {
67 Thread.sleep(1000);
68 } catch (InterruptedException e) {
69 System.out.println("Main thread interrupted, continuing execution.");
70 }
71 }
72
73 if (privateFinalizeInvoked) {
74 throw new RuntimeException("private finalize method invoked");
75 }
76 if (finalizedCount.get() != (count+1)) {
77 throw new RuntimeException("Unexpected count=" + finalizedCount +
78 " expected=" + (count+1));
79 }
80 if (finalizedSum.get() != (sum+expected)) {
81 throw new RuntimeException("Unexpected sum=" + finalizedSum +
82 " prev=" + sum + " value=" + expected);
83 }
84 }
85
86 static void patchPrivateFinalize() throws IOException {
87 // patch the private f_nal_ze method name to "finalize"
88 String testClasses = System.getProperty("test.classes", ".");
89 Path p = Paths.get(testClasses, "FinalizeOverride$PrivateFinalize.class");
90 byte[] bytes = Files.readAllBytes(p);
91 int len = "f_nal_ze".length();
92 for (int i=0; i < bytes.length-len; i++) {
93 if (bytes[i] == 'f' &&
94 bytes[i+1] == '_' &&
95 bytes[i+2] == 'n' &&
96 bytes[i+3] == 'a' &&
97 bytes[i+4] == 'l' &&
98 bytes[i+5] == '_' &&
99 bytes[i+6] == 'z' &&
100 bytes[i+7] == 'e')
101 {
102 // s%_%i%
103 bytes[i+1] = 'i';
104 bytes[i+5] = 'i';
105 break;
106 }
107 }
108 Files.write(p, bytes);
109 }
110
111 static class Base {
112 protected int value;
113 Base(int v) {
114 this.value = v;
115 }
116 int called() {
117 finalizedSum.addAndGet(value);
118 return value;
119 }
120 protected void finalize() {
121 System.out.println("Base.finalize() sum += " + called());
122 finalizedCount.incrementAndGet();
123 }
124 }
125 static class PublicFinalize extends Base {
126 PublicFinalize(int v) {
127 super(v);
128 }
129 public void finalize() {
130 finalizedSum.addAndGet(value * 100);
131 System.out.println("PublicFinalize.finalize() sum += " + called() +
132 "+"+value+"*100");
133 finalizedCount.incrementAndGet();
134 }
135 }
136 static class Subclass extends Base {
137 Subclass(int v) {
138 super(v);
139 }
140 protected void finalize() {
141 // no value added to sum
142 System.out.println("Subclass.finalize() sum += 0");
143 finalizedCount.incrementAndGet();
144 }
145 }
146 static class SubSubclass extends Subclass {
147 SubSubclass(int v) {
148 super(v);
149 }
150 protected final void finalize() {
151 finalizedSum.addAndGet(value);
152 System.out.println("SubSubclass.finalize() sum +=" +value);
153 finalizedCount.incrementAndGet();
154 }
155 }
156 static class PrivateFinalize extends Base {
157 PrivateFinalize(int v) {
158 super(v);
159 }
160 private void f_nal_ze() {
161 // finalization catches any exception
162 System.out.println("Error: private finalize invoked!!");
163 privateFinalizeInvoked = true;
164 finalizedCount.incrementAndGet();
165 }
166 }
167 static class NoOverride extends PrivateFinalize {
168 NoOverride(int v) {
169 super(v);
170 }
171 }
172 }