databasecachemanager.java

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/**
 * $RCSfile: DatabaseCacheManager.java,v $
 * $Revision: 1.20 $
 * $Date: 2002/07/29 16:08:47 $
 *
 * Copyright (C) 1999-2001 CoolServlets, Inc. All rights reserved.
 *
 * This software is the proprietary information of CoolServlets, Inc.
 * Use is subject to license terms.
 */

package com.jivesoftware.forum.database;

import com.jivesoftware.util.*;
import com.jivesoftware.forum.*;

/**
 * Central cache management of all caches used by Jive Forums. Cache sizes are
 * stored as the following Jive property values: <ul>
 *
 *      <li> <tt>cache.userCache.size</tt> -- cache for User objects.
 *      <li> <tt>cache.userCache.size</tt> -- cache mapping usernames to IDs.
 *      <li> <tt>cache.groupCache.size</tt> -- cache for Group objects.
 *      <li> <tt>cache.groupIDCache.size</tt> -- cache mapping group names to IDs.
 *      <li> <tt>cache.groupMemberCache.size</tt> -- cache for storing the lists
 *              of users in groups.
 *      <li> <tt>cache.categoryCache.size</tt> -- cache for ForumCategory
 *              objects. Because of the way most skins are implemented, it's
 *              generally very important to make sure your category cache is
 *              large enough to hold all category objects in cache at once.
 *      <li> <tt>cache.forumCache.size</tt> -- cache for Forum objects.
 *              Because most skins display a listing of all forums at once, it's
 *              very important to make sure your forum cache is large enough to
 *              hold all forum objects in cache at once.
 *      <li> <tt>cache.forumIDCache.size</tt> -- cache mapping forum names to IDs.
 *      <li> <tt>cache.threadCache.size</tt> -- cache for thread objects.
 *      <li> <tt>cache.messageCache.size</tt> -- cache for message objects.
 *              This cache should be relatively large compared to other caches
 *              since the text of messages can eat a lot of memory.
 *      <li> <tt>cache.attachmentCache.size</tt> -- cache for Attachment objects.
 *      <li> <tt>cache.watchCache.size</tt> -- cache for Watch objects.
 *      <li> <tt>cache.userPermsCache.size</tt> -- cache to store user permissions
 *              on objects.
 *      <li> <tt>cache.queryCache.size</tt> -- cache for results of ResultFilter
 *              queries.
 *      <li> <tt>cache.shortTermQueryCache.size</tt> -- short-term cache for
 *              results of ResultFilter queries.
 *      <li> <tt>cache.shortTermQueryCache.time</tt> -- the amount of time objects
 *              should live in the short-term cache (in milleseconds). The default
 *              value is 0, which means that the short-term cache is disabled.
 *              If you wish to use short-term cache, a good value is 10000
 *              (10 seconds).
 *      </ul>
 *
 * All values should be in bytes. Cache can also be globally enabled or disabled.
 * This value is stored as the <tt>cache.enabled</tt> Jive property. For sites
 * with extreme traffic (500K or more forum page views per day) a short-term
 * query cache can be enabled to that cache invalidations don't happen more than
 * once every X seconds (where X is the lifetime of objects in the short-term
 * cache). To enable the short-term query cache, set the
 * <tt>cache.shortTermQueryCache.time</tt> Jive property (expiration time in
 * milleseconds) -- for example, to 10000, so that query cache invalidations
 * only happen once every 10 seconds.
 *
 * @author Matt Tucker
 */
public class DatabaseCacheManager {

    /**
     * A cache for User objects.
     */
    public Cache userCache;

    /**
     * A cache for username to userID mappings.
     */
    public Cache userIDCache;

    /**
     * A cache for Group objects.
     */
    public Cache groupCache;

    /**
     * A cache for group name to groupID mappings.
     */
    public Cache groupIDCache;

    /**
     * A cache for Category objects.
     */
    public Cache categoryCache;

    /**
     * A cache for Forum objects.
     */
    public Cache forumCache;

    /**
     * A cache for forum name to forumID mappings.
     */
    public Cache forumIDCache;

    /**
     * A cache for ForumThread objects.
     */
    public Cache threadCache;

    /**
     * A cache for ForumMessage objects.
     */
    public Cache messageCache;

    /**
     * A cache for permissions.
     */
    public Cache userPermsCache;

    /**
     * A cache for database query results generated by the use of ResultFilters.
     * Queries will either be for counts of objects, or lists of objects.
     */
    public Cache queryCache;

    /**
     * A short-term cache for query results.
     */
    public Cache shortTermQueryCache;

    /**
     * A cache for Watch objects.
     */
    public Cache watchCache;

    /**
     * A cache for the list of users in groups and lists of the groups
     * that users belong to.
     */
    public Cache groupMemberCache;

    /**
     * A cache of user message counts. This greatly helps for skins that
     * show the number of messages a user has posted next to each of their
     * messages. Each userManager implementation is responsible for actually
     * using this cache at its option.
     */
    public Cache userMessageCountCache;

    /**
     * A cache for attachment objects.
     */
    public Cache attachmentCache;

    private boolean cacheEnabled = true;
    private boolean shortTermQueryCacheEnabled = false;

    /**
     * Creates a new cache manager.
     */
    public DatabaseCacheManager() {
        initCache();
    }

    /**
     * Initializes all caches with the correct size and expiration time.
     */
    private void initCache() {
        // This mehthod can be called externally -- for example, after switching
        // from local to clustered cache or vice versa. In that case, we only
        // need to clear out the query caches.
        if (queryCache != null) {  queryCache.clear();  }
        if (shortTermQueryCache != null) {  shortTermQueryCache.clear();  }

        long HOUR = JiveGlobals.HOUR;

        // See if cache is supposed to be enabled.
        String enabled = JiveGlobals.getJiveProperty("cache.enabled");
        if (enabled != null) {
            try { cacheEnabled = Boolean.valueOf(enabled).booleanValue(); }
            catch (Exception e) { }
        }

        // Default cache sizes (small)
        int categoryCacheSize = 256*1024;     // 1/4 MB
        int forumCacheSize = 512*1024;        // 1/2 MB
        int forumIDCacheSize = 64*1024;       // 1/16 MB
        int threadCacheSize = 512*1024;       // 1/2 MB
        int messageCacheSize = 1152*1024;     // 5/4 MB
        int userCacheSize = 512*1024;         // 1/2 MB
        int userIDCacheSize = 128*1024;       // 1/8 MB
        int userPermCacheSize = 256*1024;     // 1/4 MB
        int groupCacheSize = 128*1024;        // 1/8 MB
        int groupIDCacheSize = 128*1024;      // 1/8 MB
        int watchCacheSize = 128*1024;        // 1/8 MB

        int userMsgCountCacheSize = 64*1024;    // 1/16 MB
        int queryCacheSize = 512*1024;          // 1/2 MB

        int groupMemberCacheSize = 16*1024;
        int attachmentCacheSize = 64*1024;     // 1/16 MB

        String cacheSize = null;

        cacheSize = JiveGlobals.getJiveProperty("cache.categoryCache.size");
        if (cacheSize != null) {
            try {  categoryCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.forumCache.size");
        if (cacheSize != null) {
            try {  forumCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.forumIDCache.size");
        if (cacheSize != null) {
            try { forumIDCacheSize = Integer.parseInt(cacheSize); }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.threadCache.size");
        if (cacheSize != null) {
            try {  threadCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.messageCache.size");
        if (cacheSize != null) {
            try {  messageCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.userCache.size");
        if (cacheSize != null) {
            try {  userCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.userIDCache.size");
        if (cacheSize != null) {
            try {  userIDCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.userPermsCache.size");
        if (cacheSize != null) {
            try {  userPermCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.groupCache.size");
        if (cacheSize != null) {
            try {  groupCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.groupIDCache.size");
        if (cacheSize != null) {
            try {  groupIDCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.watchCache.size");
        if (cacheSize != null) {
            try {  watchCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.userMsgCountCache.size");
        if (cacheSize != null) {
            try {  userMsgCountCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.queryCache.size");
        if (cacheSize != null) {
            try {  queryCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        /*
        cacheSize = JiveGlobals.getJiveProperty("cache.shortTermQueryCache.size");
        if (cacheSize != null) {
            try {  shortTermQueryCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheTime = JiveGlobals.getJiveProperty("cache.shortTermQueryCache.time");
        if (cacheTime != null) {
            try {  shortTermQueryCacheTime = Long.parseLong(cacheTime);  }
            catch (Exception e) { }
        }
        */
        cacheSize = JiveGlobals.getJiveProperty("cache.watchCache.size");
        if (cacheSize != null) {
            try {  watchCacheSize = Integer.parseInt(cacheSize);  }
            catch (Exception e) { }
        }
        cacheSize = JiveGlobals.getJiveProperty("cache.groupMemberCache.size");
        if (cacheSize != null) {
            try {  groupMemberCacheSize = Integer.parseInt(cacheSize);  }