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;
27
28 /**
29 * Thrown when an application tries to load in a class through its
30 * string name using:
31 * <ul>
32 * <li>The <code>forName</code> method in class <code>Class</code>.
33 * <li>The <code>findSystemClass</code> method in class
34 * <code>ClassLoader</code> .
35 * <li>The <code>loadClass</code> method in class <code>ClassLoader</code>.
36 * </ul>
37 * <p>
38 * but no definition for the class with the specified name could be found.
39 *
40 * <p>As of release 1.4, this exception has been retrofitted to conform to
41 * the general purpose exception-chaining mechanism. The "optional exception
42 * that was raised while loading the class" that may be provided at
43 * construction time and accessed via the {@link #getException()} method is
44 * now known as the <i>cause</i>, and may be accessed via the {@link
45 * Throwable#getCause()} method, as well as the aforementioned "legacy method."
46 *
47 * @author unascribed
48 * @see java.lang.Class#forName(java.lang.String)
49 * @see java.lang.ClassLoader#findSystemClass(java.lang.String)
50 * @see java.lang.ClassLoader#loadClass(java.lang.String, boolean)
51 * @since 1.0
52 */
53 public class ClassNotFoundException extends ReflectiveOperationException {
54 /**
55 * use serialVersionUID from JDK 1.1.X for interoperability
56 */
57 private static final long serialVersionUID = 9176873029745254542L;
58
59 /**
60 * This field holds the exception ex if the
61 * ClassNotFoundException(String s, Throwable ex) constructor was
62 * used to instantiate the object
63 * @serial
64 * @since 1.2
65 */
66 private Throwable ex;
67
68 /**
69 * Constructs a <code>ClassNotFoundException</code> with no detail message.
70 */
71 public ClassNotFoundException() {
72 super((Throwable)null); // Disallow initCause
73 }
74
75 /**
76 * Constructs a <code>ClassNotFoundException</code> with the
77 * specified detail message.
78 *
79 * @param s the detail message.
80 */
81 public ClassNotFoundException(String s) {
82 super(s, null); // Disallow initCause
83 }
84
85 /**
86 * Constructs a <code>ClassNotFoundException</code> with the
87 * specified detail message and optional exception that was
88 * raised while loading the class.
89 *
90 * @param s the detail message
91 * @param ex the exception that was raised while loading the class
92 * @since 1.2
93 */
94 public ClassNotFoundException(String s, Throwable ex) {
95 super(s, null); // Disallow initCause
96 this.ex = ex;
97 }
98
99 /**
100 * Returns the exception that was raised if an error occurred while
101 * attempting to load the class. Otherwise, returns {@code null}.
102 *
103 * <p>This method predates the general-purpose exception chaining facility.
104 * The {@link Throwable#getCause()} method is now the preferred means of
105 * obtaining this information.
106 *
107 * @return the <code>Exception</code> that was raised while loading a class
108 * @since 1.2
109 */
110 public Throwable getException() {
111 return ex;
112 }
113
114 /**
115 * Returns the cause of this exception (the exception that was raised
116 * if an error occurred while attempting to load the class; otherwise
117 * {@code null}).
118 *
119 * @return the cause of this exception.
120 * @since 1.4
121 */
122 public Throwable getCause() {
123 return ex;
124 }
125 }
|
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;
27
28 import java.io.IOException;
29 import java.io.ObjectInputStream;
30 import java.io.ObjectOutputStream;
31 import java.io.ObjectStreamField;
32
33 /**
34 * Thrown when an application tries to load in a class through its
35 * string name using:
36 * <ul>
37 * <li>The <code>forName</code> method in class <code>Class</code>.
38 * <li>The <code>findSystemClass</code> method in class
39 * <code>ClassLoader</code> .
40 * <li>The <code>loadClass</code> method in class <code>ClassLoader</code>.
41 * </ul>
42 * <p>
43 * but no definition for the class with the specified name could be found.
44 *
45 * <p>As of release 1.4, this exception has been retrofitted to conform to
46 * the general purpose exception-chaining mechanism. The "optional exception
47 * that was raised while loading the class" that may be provided at
48 * construction time and accessed via the {@link #getException()} method is
49 * now known as the <i>cause</i>, and may be accessed via the {@link
50 * Throwable#getCause()} method, as well as the aforementioned "legacy method."
51 *
52 * @author unascribed
53 * @see java.lang.Class#forName(java.lang.String)
54 * @see java.lang.ClassLoader#findSystemClass(java.lang.String)
55 * @see java.lang.ClassLoader#loadClass(java.lang.String, boolean)
56 * @since 1.0
57 */
58 public class ClassNotFoundException extends ReflectiveOperationException {
59 /**
60 * use serialVersionUID from JDK 1.1.X for interoperability
61 */
62 private static final long serialVersionUID = 9176873029745254542L;
63
64 /**
65 * Constructs a <code>ClassNotFoundException</code> with no detail message.
66 */
67 public ClassNotFoundException() {
68 super((Throwable)null); // Disallow initCause
69 }
70
71 /**
72 * Constructs a <code>ClassNotFoundException</code> with the
73 * specified detail message.
74 *
75 * @param s the detail message.
76 */
77 public ClassNotFoundException(String s) {
78 super(s, null); // Disallow initCause
79 }
80
81 /**
82 * Constructs a <code>ClassNotFoundException</code> with the
83 * specified detail message and optional exception that was
84 * raised while loading the class.
85 *
86 * @param s the detail message
87 * @param ex the exception that was raised while loading the class
88 * @since 1.2
89 */
90 public ClassNotFoundException(String s, Throwable ex) {
91 super(s, ex); // Disallow initCause
92 }
93
94 /**
95 * Returns the exception that was raised if an error occurred while
96 * attempting to load the class. Otherwise, returns {@code null}.
97 *
98 * <p>This method predates the general-purpose exception chaining facility.
99 * The {@link Throwable#getCause()} method is now the preferred means of
100 * obtaining this information.
101 *
102 * @return the <code>Exception</code> that was raised while loading a class
103 * @since 1.2
104 */
105 public Throwable getException() {
106 return super.getCause();
107 }
108
109 /**
110 * Serializable fields for ClassNotFoundException.
111 *
112 * @serialField ex Throwable
113 */
114 private static final ObjectStreamField[] serialPersistentFields = {
115 new ObjectStreamField("ex", Throwable.class)
116 };
117
118 /*
119 * Reconstitutes the ClassNotFoundException instance from a stream
120 * and initialize the cause properly when deserializing from an older
121 * version.
122 *
123 * The getException and getCause method returns the private "ex" field
124 * in the older implementation and ClassNotFoundException::cause
125 * was set to null.
126 */
127 private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException {
128 ObjectInputStream.GetField fields = s.readFields();
129 Throwable exception = (Throwable) fields.get("ex", null);
130 if (exception != null) {
131 setCause(exception);
132 }
133 }
134
135 /*
136 * To maintain compatibility with older implementation, write a serial
137 * "ex" field with the cause as the value.
138 */
139 private void writeObject(ObjectOutputStream out) throws IOException {
140 ObjectOutputStream.PutField fields = out.putFields();
141 fields.put("ex", super.getCause());
142 out.writeFields();
143 }
144 }
|