2 * Copyright (C) 2001, 2002 The Mir-coders group
4 * This file is part of Mir.
6 * Mir is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * Mir is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with Mir; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
20 * In addition, as a special exception, The Mir-coders gives permission to link
21 * the code of this program with the com.oreilly.servlet library, any library
22 * licensed under the Apache Software License, The Sun (tm) Java Advanced
23 * Imaging library (JAI), The Sun JIMI library (or with modified versions of
24 * the above that use the same license as the above), and distribute linked
25 * combinations including the two. You must obey the GNU General Public
26 * License in all respects for all of the code used other than the above
27 * mentioned libraries. If you modify this file, you may extend this exception
28 * to your version of the file, but you are not obligated to do so. If you do
29 * not wish to do so, delete this exception statement from your version.
32 package mir.storage.store;
35 * Title: StoreContainer
37 * Description: This is the bucket object for one type of StorableObjects,
38 * mainy a linked list of StoreIdenfiers. On use or creation
39 * an object stored in StoreIdentifier is put to head of the
40 * list. if maximum size of the list is reached, the
41 * StoreIdentifier at the end of the list is released.
43 * Copyright: Copyright (c) 2002
49 import java.util.LinkedList;
50 import java.util.ListIterator;
52 import javax.servlet.http.HttpServletRequest;
54 import mir.log.LoggerWrapper;
55 import mir.misc.StringUtil;
57 public class StoreContainer {
58 private final static int DEFAULT_SIZE = 10;
59 private static int uniqueCounter = 10000;
61 private LinkedList container;
62 private StoreContainerType stocType;
63 private int maxSize = DEFAULT_SIZE, uniqueId;
64 private int addCount = 0, removeCount = 0, storeOutCount;
65 private int hitCount = 0, missCount = 0;
66 private static ObjectStore o_store = ObjectStore.getInstance();
68 protected LoggerWrapper logger = new LoggerWrapper("Database.ObjectStore");
70 // avoid construction without parameters
71 private StoreContainer() {};
74 public StoreContainer(StoreContainerType stoc_type) {
75 this.uniqueId = ++uniqueCounter;
76 this.stocType = stoc_type;
77 this.container = new LinkedList();
78 int defaultSize = stoc_type.getDefaultSize();
79 String confProperty = stoc_type.getConfPrefix() + ".DefaultSize";
80 String confedSize = o_store.getConfProperty(confProperty);
81 if (confedSize != null) {
82 this.maxSize = StringUtil.parseInt(confedSize, defaultSize);
86 public StoreContainer(StoreContainerType stoc_type, int maxSize) {
88 this.maxSize = maxSize;
91 public synchronized StorableObject use(StoreIdentifier sid) {
92 int hit = container.indexOf(sid);
94 StoreIdentifier hitSid = (StoreIdentifier) container.get(hit);
104 public boolean has(StoreIdentifier sid) {
105 return container.contains(sid);
108 public void add(StoreIdentifier sid) {
109 if (sid != null && sid.hasReference()) {
112 logger.debug("OBJECTStore: tried to add sid " + sid.toString() + " that was already in store.");
115 container.addFirst(sid);
123 * Method: invalidate(StorableObject sto)
124 * Description: finds @see StorableObject, propagates invalidation to
125 * @see StoreIdentifier and removes StoreIdentifier from
128 public synchronized void invalidate(StoreIdentifier search_sid) {
129 if (search_sid != null) {
130 int hit = container.indexOf(search_sid);
132 StoreIdentifier sid = (StoreIdentifier) container.get(hit);
133 container.remove(sid);
140 public synchronized void invalidate() {
142 while (container.size() > 0) {
143 sid = (StoreIdentifier) container.getLast();
144 container.removeLast();
151 * Description: readjusts StoreContainer size to value.
154 public void setSize(int size) {
161 private void shrinkIfNecessary() {
162 shrinkToSize(maxSize);
165 private void shrinkToSize(int size) {
166 if (size < container.size()) {
168 while (size < container.size()) {
169 StoreIdentifier sid = (StoreIdentifier) container.getLast();
170 container.remove(sid);
177 private synchronized void moveToHead(StoreIdentifier sid) {
179 container.remove(sid);
180 container.addFirst(sid);
186 * Description: gives out statistical Information, viewable via
187 * @see ServletStoreInfo.
191 public String toString() {
195 public String toHtml(HttpServletRequest req) {
196 boolean showingContent = false;
198 long divisor = hitCount + missCount;
200 hitRatio = (float) hitCount / (float) divisor;
203 StringBuffer sb = new StringBuffer("StoreContainer id: ");
204 sb.append(uniqueId).append(" for ");
205 sb.append(stocType.toString());
207 String show = req.getParameter("stoc_show");
208 if (show != null && show.equals("" + uniqueId)) {
209 // show all entries in container
210 sb.append(" [<b>showing</b>]");
211 showingContent = true;
214 sb.append(" [<a href=\"?stoc_show=" + uniqueId + "\">show</a>]");
216 sb.append("\n [current/maximum size: ");
217 sb.append(container.size()).append("/").append(maxSize);
218 sb.append("]\n [added/stored out/removed: ").append(addCount).append("/");
219 sb.append(storeOutCount).append("/").append(removeCount).append(
220 "]\n [hit/miss/ratio: ");
221 sb.append(hitCount).append("/").append(missCount).append("/");
222 sb.append(hitRatio).append("%]\n");
224 if (showingContent) {
225 sb.append(" <b>Container contains following references:</b>\n ");
226 ListIterator it = container.listIterator();
227 while (it.hasNext()) {
228 StoreIdentifier sid = (StoreIdentifier) it.next();
229 sb.append(sid.toString()).append("\n ");
231 sb.append("<b>End of List</b>\n\n");
235 return sb.toString();