1 /*
2 * Copyright (c) 1999, 2018, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package java.lang.reflect;
27
28 import java.io.IOException;
29 import java.io.ObjectInputStream;
30 import java.io.ObjectOutputStream;
31 import java.io.ObjectStreamField;
32 import jdk.internal.access.SharedSecrets;
33
34 /**
35 * Thrown by a method invocation on a proxy instance if its invocation
36 * handler's {@link InvocationHandler#invoke invoke} method throws a
37 * checked exception (a {@code Throwable} that is not assignable
38 * to {@code RuntimeException} or {@code Error}) that
39 * is not assignable to any of the exception types declared in the
40 * {@code throws} clause of the method that was invoked on the
41 * proxy instance and dispatched to the invocation handler.
42 *
43 * <p>An {@code UndeclaredThrowableException} instance contains
44 * the undeclared checked exception that was thrown by the invocation
45 * handler, and it can be retrieved with the
46 * {@code getUndeclaredThrowable()} method.
47 * {@code UndeclaredThrowableException} extends
48 * {@code RuntimeException}, so it is an unchecked exception
49 * that wraps a checked exception.
50 *
51 * <p>As of release 1.4, this exception has been retrofitted to
52 * conform to the general purpose exception-chaining mechanism. The
53 * "undeclared checked exception that was thrown by the invocation
54 * handler" that may be provided at construction time and accessed via
55 * the {@link #getUndeclaredThrowable()} method is now known as the
56 * <i>cause</i>, and may be accessed via the {@link
57 * Throwable#getCause()} method, as well as the aforementioned "legacy
58 * method."
59 *
60 * @author Peter Jones
61 * @see InvocationHandler
62 * @since 1.3
63 */
64 public class UndeclaredThrowableException extends RuntimeException {
65 static final long serialVersionUID = 330127114055056639L;
66
67 /**
68 * Constructs an {@code UndeclaredThrowableException} with the
69 * specified {@code Throwable}.
70 *
71 * @param undeclaredThrowable the undeclared checked exception
72 * that was thrown
73 */
74 public UndeclaredThrowableException(Throwable undeclaredThrowable) {
75 super(null, undeclaredThrowable); // Disallow initCause
76 }
77
78 /**
79 * Constructs an {@code UndeclaredThrowableException} with the
80 * specified {@code Throwable} and a detail message.
81 *
82 * @param undeclaredThrowable the undeclared checked exception
83 * that was thrown
84 * @param s the detail message
85 */
86 public UndeclaredThrowableException(Throwable undeclaredThrowable,
87 String s)
88 {
89 super(s, undeclaredThrowable); // Disallow initCause
90 }
91
92 /**
93 * Returns the {@code Throwable} instance wrapped in this
94 * {@code UndeclaredThrowableException}, which may be {@code null}.
95 *
96 * <p>This method predates the general-purpose exception chaining facility.
97 * The {@link Throwable#getCause()} method is now the preferred means of
98 * obtaining this information.
99 *
100 * @return the undeclared checked exception that was thrown
101 */
102 public Throwable getUndeclaredThrowable() {
103 return super.getCause();
104 }
105
106 /**
107 * Serializable fields for UndeclaredThrowableException.
108 *
109 * @serialField undeclaredThrowable Throwable
110 */
111 private static final ObjectStreamField[] serialPersistentFields = {
112 new ObjectStreamField("undeclaredThrowable", Throwable.class)
113 };
114
115 /*
116 * Reconstitutes the UndeclaredThrowableException instance from a stream
117 * and initialize the cause properly when deserializing from an older
118 * version.
119 */
120 private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException {
121 ObjectInputStream.GetField fields = s.readFields();
122 Throwable exception = (Throwable) fields.get("undeclaredThrowable", null);
123 if (exception != null) {
124 SharedSecrets.getJavaLangAccess().setCause(this, exception);
125 }
126 }
127
128 /*
129 * To maintain compatibility with older implementation, write a serial
130 * "ex" field with the cause as the value.
131 */
132 private void writeObject(ObjectOutputStream out) throws IOException {
133 ObjectOutputStream.PutField fields = out.putFields();
134 fields.put("undeclaredThrowable", super.getCause());
135 out.writeFields();
136 }
137 }