KickJava   Java API By Example, From Geeks To Geeks.

Java > Open Source Codes > org > apache > excalibur > instrument > Instrumentable


1 /*
2
3  ============================================================================
4                    The Apache Software License, Version 1.1
5  ============================================================================
6  
7  Copyright (C) 1999-2003 The Apache Software Foundation. All rights reserved.
8  
9  Redistribution and use in source and binary forms, with or without modifica-
10  tion, are permitted provided that the following conditions are met:
11  
12  1. Redistributions of source code must retain the above copyright notice,
13     this list of conditions and the following disclaimer.
14  
15  2. Redistributions in binary form must reproduce the above copyright notice,
16     this list of conditions and the following disclaimer in the documentation
17     and/or other materials provided with the distribution.
18  
19  3. The end-user documentation included with the redistribution, if any, must
20     include the following acknowledgment: "This product includes software
21     developed by the Apache Software Foundation (http://www.apache.org/)."
22     Alternately, this acknowledgment may appear in the software itself, if
23     and wherever such third-party acknowledgments normally appear.
24  
25  4. The names "Jakarta", "Avalon", "Excalibur" and "Apache Software Foundation"
26     must not be used to endorse or promote products derived from this software
27     without prior written permission. For written permission, please contact
28     apache@apache.org.
29  
30  5. Products derived from this software may not be called "Apache", nor may
31     "Apache" appear in their name, without prior written permission of the
32     Apache Software Foundation.
33  
34  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
35  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
36  FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
37  APACHE SOFTWARE FOUNDATION OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
38  INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLU-
39  DING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
40  OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
41  ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
42  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
43  THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
44  
45  This software consists of voluntary contributions made by many individuals
46  on behalf of the Apache Software Foundation. For more information on the
47  Apache Software Foundation, please see <http://www.apache.org/>.
48  
49 */
50 package org.apache.excalibur.instrument;
51
52 /**
53  * The Instrumentable interface is to mark objects that can be sampled by an
54  * InstrumentManager. The getInstruments method may or may not be called
55  * depending on whether or not the ComponentLocator used to create the
56  * Component supports Instrumentables. In most cases, an instrumentable
57  * object should always create its internal Instruments and make use of them
58  * as if instrument data were being collected. The Instruments are optimized
59  * so as not to reduce performance when they are not being used.
60  *
61  * @author <a HREF="mailto:leif@tanukisoftware.com">Leif Mortenson</a>
62  * @version CVS $Revision: 1.2 $ $Date: 2003/02/20 17:07:55 $
63  * @since 4.1
64  */
65 public interface Instrumentable
66 {
67     /**
68      * Empty Instrument array for use in hierarchical Instrumentable systems.
69      */
70     Instrument[] EMPTY_INSTRUMENT_ARRAY = new Instrument[]{};
71
72     /**
73      * Empty Instrumentable array for use in hierarchical Instrumentable
74      * systems.
75      */
76     Instrumentable[] EMPTY_INSTRUMENTABLE_ARRAY = new Instrumentable[]{};
77
78     /**
79      * Sets the name for the Instrumentable. The Instrumentable Name is used
80      * to uniquely identify the Instrumentable during the configuration of
81      * the InstrumentManager and to gain access to an InstrumentableDescriptor
82      * through the InstrumentManager. The value should be a string which does
83      * not contain spaces or periods.
84      * <p>
85      * This value may be set by a parent Instrumentable, or by the
86      * InstrumentManager using the value of the 'instrumentable' attribute in
87      * the configuration of the component.
88      *
89      * @param name The name used to identify a Instrumentable.
90      */
91     void setInstrumentableName( String JavaDoc name );
92
93     /**
94      * Gets the name of the Instrumentable.
95      *
96      * @return The name used to identify a Instrumentable.
97      */
98     String JavaDoc getInstrumentableName();
99
100     /**
101      * Obtain a reference to all the Instruments that the Instrumentable object
102      * wishes to expose. All sampling is done directly through the
103      * Instruments as opposed to the Instrumentable interface.
104      *
105      * @return An array of the Instruments available for profiling. Should
106      * never be null. If there are no Instruments, then
107      * EMPTY_INSTRUMENT_ARRAY can be returned. This should never be
108      * the case though unless there are child Instrumentables with
109      * Instruments.
110      */
111     Instrument[] getInstruments();
112
113     /**
114      * Any Object which implements Instrumentable can also make use of other
115      * Instrumentable child objects. This method is used to tell the
116      * InstrumentManager about them.
117      *
118      * @return An array of child Instrumentables. This method should never
119      * return null. If there are no child Instrumentables, then
120      * EMPTY_INSTRUMENTABLE_ARRAY can be returned.
121      */
122     Instrumentable[] getChildInstrumentables();
123 }
124
125
Popular Tags