1 /*
2 * Copyright (c) 1998, 2014, 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 /* @test
25 * @bug 4099660 4102938
26 * @summary Remote classes not extending RemoteObject should be able to
27 * implement hashCode() and equals() methods so that instances
28 * can be successfully compared to RemoteObject instances
29 * (specifically: stubs) that contain the instance's RemoteRef.
30 * @author Peter Jones
31 *
32 * @build NotExtending_Stub NotExtending_Skel
33 * @run main/othervm/timeout=240 NotExtending
34 */
35
36
37 import java.rmi.*;
38 import java.rmi.server.*;
39
40 public class NotExtending implements Remote {
41
42 /** remote stub for this server instance */
43 private Remote stub;
44 /** value of stub's hash code */
45 private int hashValue;
46 /** true if the hashValue field has been initialized */
47 private boolean hashValueInitialized = false;
48
49 public NotExtending() throws RemoteException {
50 stub = UnicastRemoteObject.exportObject(this);
51 setHashValue(stub.hashCode());
52 }
53
54 private void setHashValue(int value) {
55 hashValue = value;
56 hashValueInitialized = true;
57 }
58
59 public int hashCode() {
60 /*
61 * Test fails with a RuntimeException if the hashCode() method is
62 * called (during the export procedure) before the correct hash
63 * value has been initialized.
64 */
65 if (!hashValueInitialized) {
66 throw new RuntimeException(
67 "hashCode() invoked before hashValue initialized");
68 }
69 return hashValue;
70 }
71
72 public boolean equals(Object obj) {
73 return stub.equals(obj);
74 }
75
76 public static void main(String[] args) throws Exception {
77 /*
78 * The following line is required with the JDK 1.2 VM so that the
79 * VM can exit gracefully when this test completes. Otherwise, the
80 * conservative garbage collector will find a handle to the server
81 * object on the native stack and not clear the weak reference to
82 * it in the RMI runtime's object table.
83 */
84 Object dummy = new Object();
85
86 NotExtending server;
87 try {
88 /*
89 * Verify that hashCode() is not invoked before it is
90 * initialized. Tests bugid 4102938.
91 */
92 server = new NotExtending();
93 System.err.println("Server exported without invoking hashCode().");
94
95 /*
96 * Verify that passing stub to server's equals() method
97 * returns true.
98 */
99 if (server.equals(server.stub)) {
100 System.err.println(
101 "Passing stub to server's equals() method succeeded.");
102 } else {
103 throw new RuntimeException(
104 "passing stub to server's equals() method failed");
105 }
106
107 /*
108 * Verify that passing server to stub's equals() method
109 * returns true. Tests bugid 4099660.
110 */
111 if (server.stub.equals(server)) {
112 System.err.println(
113 "Passing server to stub's equals() method succeeded.");
114 } else {
115 throw new RuntimeException(
116 "passing server to stub's equals() method failed");
117 }
118
119 } finally {
120 server = null;
121 flushCachedRefs();
122 }
123 }
124
125 /**
126 * Force desperate garbage collection so that soft references
127 * will be cleared.
128 *
129 * This method is required with the JDK 1.1.x RMI runtime so that the
130 * VM can exit gracefully when this test completes. See bugid 4006356.
131 */
132 public static void flushCachedRefs() {
133 java.util.Vector chain = new java.util.Vector();
134 try {
135 while (true) {
136 int[] hungry = new int[65536];
137 chain.addElement(hungry);
138 }
139 } catch (OutOfMemoryError e) {
140 }
141 }
142 }