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 any library licensed under the Apache Software License,
22 * The Sun (tm) Java Advanced Imaging library (JAI), The Sun JIMI library
23 * (or with modified versions of the above that use the same license as the above),
24 * and distribute linked combinations including the two. You must obey the
25 * GNU General Public License in all respects for all of the code used other than
26 * the above mentioned libraries. If you modify this file, you may extend this
27 * exception to your version of the file, but you are not obligated to do so.
28 * If you do not wish to do so, delete this exception statement from your version.
31 package mir.storage.store;
34 * Title: StoreContainer
36 * Description: This is the bucket object for one type of StorableObjects,
37 * mainy a linked list of StoreIdenfiers. On use or creation
38 * an object stored in StoreIdentifier is put to head of the
39 * list. if maximum size of the list is reached, the
40 * StoreIdentifier at the end of the list is released.
42 * Copyright: Copyright (c) 2002
48 import java.util.LinkedList;
49 import java.util.ListIterator;
51 import javax.servlet.http.HttpServletRequest;
53 import mir.log.LoggerWrapper;
54 import mir.misc.StringUtil;
56 public class StoreContainer {
57 private final static int DEFAULT_SIZE = 10;
58 private static int uniqueCounter = 10000;
60 private LinkedList container;
61 private StoreContainerType stocType;
62 private int maxSize = DEFAULT_SIZE, uniqueId;
63 private int addCount = 0, removeCount = 0, storeOutCount;
64 private int hitCount = 0, missCount = 0;
65 private static ObjectStore o_store = ObjectStore.getInstance();
67 protected LoggerWrapper logger = new LoggerWrapper("Database.ObjectStore");
69 // avoid construction without parameters
70 private StoreContainer() {};
73 public StoreContainer(StoreContainerType stoc_type) {
74 this.uniqueId = ++uniqueCounter;
75 this.stocType = stoc_type;
76 this.container = new LinkedList();
77 int defaultSize = stoc_type.getDefaultSize();
78 String confProperty = stoc_type.getConfPrefix() + ".DefaultSize";
79 String confedSize = o_store.getConfProperty(confProperty);
80 if (confedSize != null) {
81 this.maxSize = StringUtil.parseInt(confedSize, defaultSize);
85 public StoreContainer(StoreContainerType stoc_type, int maxSize) {
87 this.maxSize = maxSize;
90 public synchronized StorableObject use(StoreIdentifier sid) {
91 int hit = container.indexOf(sid);
93 StoreIdentifier hitSid = (StoreIdentifier) container.get(hit);
103 public boolean has(StoreIdentifier sid) {
104 return container.contains(sid);
107 public void add(StoreIdentifier sid) {
108 if (sid != null && sid.hasReference()) {
111 logger.debug("OBJECTStore: tried to add sid " + sid.toString() + " that was already in store.");
114 container.addFirst(sid);
122 * Method: invalidate(StorableObject sto)
123 * Description: finds @see StorableObject, propagates invalidation to
124 * @see StoreIdentifier and removes StoreIdentifier from
127 public synchronized void invalidate(StoreIdentifier search_sid) {
128 if (search_sid != null) {
129 int hit = container.indexOf(search_sid);
131 StoreIdentifier sid = (StoreIdentifier) container.get(hit);
132 container.remove(sid);
139 public synchronized void invalidate() {
141 while (container.size() > 0) {
142 sid = (StoreIdentifier) container.getLast();
143 container.removeLast();
150 * Description: readjusts StoreContainer size to value.
153 public void setSize(int size) {
160 private void shrinkIfNecessary() {
161 shrinkToSize(maxSize);
164 private void shrinkToSize(int size) {
165 if (size < container.size()) {
167 while (size < container.size()) {
168 StoreIdentifier sid = (StoreIdentifier) container.getLast();
169 container.remove(sid);
176 private synchronized void moveToHead(StoreIdentifier sid) {
178 container.remove(sid);
179 container.addFirst(sid);
185 * Description: gives out statistical Information, viewable via
186 * @see ServletStoreInfo.
190 public String toString() {
194 public String toHtml(HttpServletRequest req) {
195 boolean showingContent = false;
197 long divisor = hitCount + missCount;
199 hitRatio = (float) hitCount / (float) divisor;
202 StringBuffer sb = new StringBuffer("StoreContainer id: ");
203 sb.append(uniqueId).append(" for ");
204 sb.append(stocType.toString());
206 String show = req.getParameter("stoc_show");
207 if (show != null && show.equals("" + uniqueId)) {
208 // show all entries in container
209 sb.append(" [<b>showing</b>]");
210 showingContent = true;
213 sb.append(" [<a href=\"?stoc_show=" + uniqueId + "\">show</a>]");
215 sb.append("\n [current/maximum size: ");
216 sb.append(container.size()).append("/").append(maxSize);
217 sb.append("]\n [added/stored out/removed: ").append(addCount).append("/");
218 sb.append(storeOutCount).append("/").append(removeCount).append(
219 "]\n [hit/miss/ratio: ");
220 sb.append(hitCount).append("/").append(missCount).append("/");
221 sb.append(hitRatio).append("%]\n");
223 if (showingContent) {
224 sb.append(" <b>Container contains following references:</b>\n ");
225 ListIterator it = container.listIterator();
226 while (it.hasNext()) {
227 StoreIdentifier sid = (StoreIdentifier) it.next();
228 sb.append(sid.toString()).append("\n ");
230 sb.append("<b>End of List</b>\n\n");
234 return sb.toString();