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Java > Open Source Codes > com > opensymphony > oscache > extra > ScopeEventListenerImpl


1 /*
2  * Copyright (c) 2002-2003 by OpenSymphony
3  * All rights reserved.
4  */
5 package com.opensymphony.oscache.extra;
6
7 import com.opensymphony.oscache.base.events.ScopeEvent;
8 import com.opensymphony.oscache.base.events.ScopeEventListener;
9 import com.opensymphony.oscache.base.events.ScopeEventType;
10
11 /**
12  * Implementation of a ScopeEventListener that keeps track of the scope flush events.
13  * We are not using any synchronized so that this does not become a bottleneck.
14  * The consequence is that on retrieving values, the operations that are
15  * currently being done won't be counted.
16  *
17  * @version $Revision: 1.1 $
18  * @author <a HREF="mailto:abergevin@pyxis-tech.com">Alain Bergevin</a>
19  */
20 public class ScopeEventListenerImpl implements ScopeEventListener {
21     /**
22      * Scope names
23      */
24     public static final String JavaDoc[] SCOPE_NAMES = {
25         null, "page", "request", "session", "application"
26     };
27
28     /**
29      * Number of known scopes
30      */
31     public static final int NB_SCOPES = SCOPE_NAMES.length - 1;
32
33     /**
34      * Page scope number
35      */
36     public static final int PAGE_SCOPE = 1;
37
38     /**
39      * Request scope number
40      */
41     public static final int REQUEST_SCOPE = 2;
42
43     /**
44      * Session scope number
45      */
46     public static final int SESSION_SCOPE = 3;
47
48     /**
49      * Application scope number
50      */
51     public static final int APPLICATION_SCOPE = 4;
52
53     /**
54      * Flush counter for all scopes.
55      * Add one to the number of scope because the array is being used
56      * from position 1 instead of 0 for convenience
57      */
58     private int[] scopeFlushCount = new int[NB_SCOPES + 1];
59
60     public ScopeEventListenerImpl() {
61     }
62
63     /**
64      * Gets the flush count for scope {@link ScopeEventListenerImpl#APPLICATION_SCOPE}.
65      * <p>
66      * @return The total number of application flush
67      */
68     public int getApplicationScopeFlushCount() {
69         return scopeFlushCount[APPLICATION_SCOPE];
70     }
71
72     /**
73      * Gets the flush count for scope {@link ScopeEventListenerImpl#PAGE_SCOPE}.
74      * @return The total number of page flush
75      */
76     public int getPageScopeFlushCount() {
77         return scopeFlushCount[PAGE_SCOPE];
78     }
79
80     /**
81      * Gets the flush count for scope {@link ScopeEventListenerImpl#REQUEST_SCOPE}.
82      * @return The total number of request flush
83      */
84     public int getRequestScopeFlushCount() {
85         return scopeFlushCount[REQUEST_SCOPE];
86     }
87
88     /**
89      * Gets the flush count for scope {@link ScopeEventListenerImpl#SESSION_SCOPE}.
90      * @return The total number of session flush
91      */
92     public int getSessionScopeFlushCount() {
93         return scopeFlushCount[SESSION_SCOPE];
94     }
95
96     /**
97      * Returns the total flush count.
98      * @return The total number of scope flush
99      */
100     public int getTotalScopeFlushCount() {
101         int total = 0;
102
103         for (int count = 1; count <= NB_SCOPES; count++) {
104             total += scopeFlushCount[count];
105         }
106
107         return total;
108     }
109
110     /**
111      * Handles all the scope flush events.
112      * @param event The scope event
113      */
114     public void scopeFlushed(ScopeEvent event) {
115         // Get the event type and process it
116 ScopeEventType eventType = event.getEventType();
117
118         if (eventType == ScopeEventType.ALL_SCOPES_FLUSHED) {
119             // All 4 scopes were flushed, increment the counters
120 for (int count = 1; count <= NB_SCOPES; count++) {
121                 scopeFlushCount[count]++;
122             }
123         } else if (eventType == ScopeEventType.SCOPE_FLUSHED) {
124             // Get back the scope from the event and increment the flush count
125 scopeFlushCount[event.getScope()]++;
126         } else {
127             // Unknown event!
128 throw new IllegalArgumentException JavaDoc("Unknown Scope Event type received");
129         }
130     }
131
132     /**
133      * Returns all the flush counter in a string form.
134      */
135     public String JavaDoc toString() {
136         StringBuffer JavaDoc returnString = new StringBuffer JavaDoc("Flush count for ");
137
138         for (int count = 1; count <= NB_SCOPES; count++) {
139             returnString.append("scope " + SCOPE_NAMES[count] + " = " + scopeFlushCount[count] + ", ");
140         }
141
142         // Remove the last 2 chars, which are ", "
143 returnString.setLength(returnString.length() - 2);
144
145         return returnString.toString();
146     }
147 }
148
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