1 /*
2 * Copyright 1999-2006 Sun Microsystems, Inc. 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. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26 package javax.management;
27
28
29 import java.util.Vector;
30
31
32 /**
33 * This class implements of the {@link javax.management.NotificationFilter NotificationFilter}
34 * interface for the {@link javax.management.AttributeChangeNotification attribute change notification}.
35 * The filtering is performed on the name of the observed attribute.
36 * <P>
37 * It manages a list of enabled attribute names.
38 * A method allows users to enable/disable as many attribute names as required.
39 *
40 * @since 1.5
41 */
42 public class AttributeChangeNotificationFilter implements NotificationFilter {
43
44 /* Serial version */
45 private static final long serialVersionUID = -6347317584796410029L;
46
47 /**
48 * @serial {@link Vector} that contains the enabled attribute names.
49 * The default value is an empty vector.
50 */
51 private Vector<String> enabledAttributes = new Vector<String>();
52
53
54 /**
55 * Invoked before sending the specified notification to the listener.
56 * <BR>This filter compares the attribute name of the specified attribute change notification
57 * with each enabled attribute name.
58 * If the attribute name equals one of the enabled attribute names,
59 * the notification must be sent to the listener and this method returns <CODE>true</CODE>.
60 *
61 * @param notification The attribute change notification to be sent.
62 * @return <CODE>true</CODE> if the notification has to be sent to the listener, <CODE>false</CODE> otherwise.
63 */
64 public synchronized boolean isNotificationEnabled(Notification notification) {
65
66 String type = notification.getType();
67
68 if ((type == null) ||
69 (type.equals(AttributeChangeNotification.ATTRIBUTE_CHANGE) == false) ||
70 (!(notification instanceof AttributeChangeNotification))) {
71 return false;
72 }
73
74 String attributeName =
75 ((AttributeChangeNotification)notification).getAttributeName();
76 return enabledAttributes.contains(attributeName);
77 }
78
79 /**
80 * Enables all the attribute change notifications the attribute name of which equals
81 * the specified name to be sent to the listener.
82 * <BR>If the specified name is already in the list of enabled attribute names,
83 * this method has no effect.
84 *
85 * @param name The attribute name.
86 * @exception java.lang.IllegalArgumentException The attribute name parameter is null.
87 */
88 public synchronized void enableAttribute(String name) throws java.lang.IllegalArgumentException {
89
90 if (name == null) {
91 throw new java.lang.IllegalArgumentException("The name cannot be null.");
92 }
93 if (!enabledAttributes.contains(name)) {
94 enabledAttributes.addElement(name);
95 }
96 }
97
98 /**
99 * Disables all the attribute change notifications the attribute name of which equals
100 * the specified attribute name to be sent to the listener.
101 * <BR>If the specified name is not in the list of enabled attribute names,
102 * this method has no effect.
103 *
104 * @param name The attribute name.
105 */
106 public synchronized void disableAttribute(String name) {
107 enabledAttributes.removeElement(name);
108 }
109
110 /**
111 * Disables all the attribute names.
112 */
113 public synchronized void disableAllAttributes() {
114 enabledAttributes.removeAllElements();
115 }
116
117 /**
118 * Gets all the enabled attribute names for this filter.
119 *
120 * @return The list containing all the enabled attribute names.
121 */
122 public synchronized Vector<String> getEnabledAttributes() {
123 return enabledAttributes;
124 }
125
126 }
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