001 /*
002 * Copyright 2005 Stephen J. McConnell.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
013 * implied.
014 *
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019 package net.dpml.test.state;
020
021 import java.rmi.Remote;
022 import java.rmi.RemoteException;
023
024 import net.dpml.logging.Logger;
025
026 /**
027 * Component implementation that exposes an active management operation.
028 *
029 * @author <a href="http://www.dpml.net">Digital Product Meta Library</a>
030 * @version 1.2.0
031 */
032 public class ManagedComponent implements Service
033 {
034 //------------------------------------------------------------------
035 // state
036 //------------------------------------------------------------------
037
038 /**
039 * The logging channel.
040 */
041 private final Logger m_logger;
042
043 private int m_count = 0;
044
045 private DefaultMonitor m_monitor;
046
047 //------------------------------------------------------------------
048 // constructor
049 //------------------------------------------------------------------
050
051 /**
052 * Creation of a new <tt>ManagedComponent</tt>.
053 *
054 * @param logger the assigned logging channel
055 */
056 public ManagedComponent( final Logger logger )
057 {
058 m_logger = logger;
059
060 m_monitor = new DefaultMonitor();
061 }
062
063 //------------------------------------------------------------------
064 // Service
065 //------------------------------------------------------------------
066
067 /**
068 * Ping the object.
069 */
070 public void ping()
071 {
072 m_count++;
073 }
074
075 //------------------------------------------------------------------
076 // operations
077 //------------------------------------------------------------------
078
079 /**
080 * Return a monitor.
081 * @return the monitor
082 */
083 public Monitor getMonitor()
084 {
085 return m_monitor;
086 }
087
088 //------------------------------------------------------------------
089 // internal
090 //------------------------------------------------------------------
091
092 /**
093 * Return the assigned logging channel.
094 * @return the logging channel
095 */
096 private Logger getLogger()
097 {
098 return m_logger;
099 }
100
101 /**
102 * Interface implemented by an internal monitor returned
103 * by the getMonitor operation.
104 */
105 public interface Monitor extends Remote
106 {
107 /**
108 * Monitor the number of times the component ping operation
109 * has been invoked.
110 * @return the access count
111 * @exception RemoteException if a remote I/O error occurs
112 */
113 int getAccessCount() throws RemoteException;
114 }
115
116 /**
117 * The default monitor implementation.
118 */
119 class DefaultMonitor implements Monitor
120 {
121 /**
122 * Return the access count.
123 * @return the access count
124 */
125 public int getAccessCount()
126 {
127 return m_count;
128 }
129 }
130 }