dbforum.java

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/**
 * $RCSfile: DbForum.java,v $
 * $Revision: 1.40 $
 * $Date: 2002/08/02 00:11:21 $
 *
 * Copyright (C) 1999-2002 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 java.util.*;
import java.util.LinkedList;
import java.util.Date;
import java.sql.*;
import java.io.*;

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

/**
 * Database implementation of the Forum interface. It loads and stores forum
 * information from a a database.
 *
 * @author Matt Tucker
 */
public class DbForum implements Forum, Cacheable {

    /** DATABASE QUERIES **/
    private static final String ALL_THREADS =
        "SELECT threadID FROM jiveThread WHERE forumID=?";
    private static final String MOVE_THREAD =
        "UPDATE jiveThread SET forumID=? WHERE threadID=?";
    private static final String MOVE_MESSAGES =
        "UPDATE jiveMessage SET forumID=? WHERE threadID=?";
    protected static final String ALL_MESSAGES_ATTACHMENTS =
        "SELECT attachmentID FROM jiveAttachment, jiveMessage WHERE " +
        "jiveAttachment.messageID=jiveMessage.messageID AND threadID=?";
    protected static final String MESSAGES_BY_NEWEST =
        "SELECT messageID FROM jiveMessage WHERE threadID=? ORDER BY creationDate DESC";
    protected static final String DELETE_MESSAGES =
        "DELETE FROM jiveMessage WHERE threadID=?";
    protected static final String DELETE_MESSAGES_PROPERTIES =
        "DELETE from jiveMessageProp WHERE messageID IN" +
        "(SELECT messageID FROM jiveMessage WHERE threadID=? AND forumID=?)";
    protected static final String DELETE_THREAD =
        "DELETE FROM jiveThread WHERE threadID=?";
    private static final String DELETE_THREAD_PROPERTIES =
        "DELETE FROM jiveThreadProp WHERE threadID=?";
    private static final String LOAD_PROPERTIES =
        "SELECT name, propValue FROM jiveForumProp WHERE forumID=?";
    private static final String DELETE_PROPERTY =
        "DELETE FROM jiveForumProp WHERE forumID=? AND name=?";
    private static final String UPDATE_PROPERTY =
        "UPDATE jiveForumProp SET propValue=? WHERE name=? AND forumID=?";
    private static final String INSERT_PROPERTY =
        "INSERT INTO jiveForumProp(forumID,name,propValue) VALUES(?,?,?)";
    private static final String LOAD_FORUM =
        "SELECT forumID, name, description, modDefaultThreadVal, " +
        "modDefaultMsgVal, modMinThreadVal, modMinMsgVal, creationDate, " +
        "modifiedDate, categoryID FROM jiveForum WHERE forumID=?";
    private static final String ADD_FORUM =
        "INSERT INTO jiveForum(forumID, categoryID, categoryIndex, name, " +
        "description, modDefaultThreadVal, modDefaultMsgVal, modMinThreadVal, " +
        "modMinMsgVal, creationDate, modifiedDate) VALUES (?,?,?,?,?,?,?,?,?,?,?)";
    private static final String SAVE_FORUM =
        "UPDATE jiveForum SET name=?, description=?, modDefaultThreadVal=?, " +
        "modDefaultMsgVal=?, modMinThreadVal=?, modMinMsgVal=?, " +
        "creationDate=?, modifiedDate=? WHERE forumID=?";
    private static final String UPDATE_FORUM_MODIFIED_DATE =
        "UPDATE jiveForum SET modifiedDate=? WHERE forumID=?";
    private static final String POPULAR_THREADS =
        "SELECT threadID, count(1) AS msgCount FROM jiveMessage, jiveForum WHERE " +
        "jiveMessage.modifiedDate > ? AND jiveMessage.forumID=? AND " +
        "jiveMessage.forumID = jiveForum.forumID AND jiveMessage.modValue >= " +
        "jiveForum.modMinMsgVal GROUP BY threadID ORDER BY msgCount DESC";
    private static final String POPULAR_THREADS_ORACLE =
        "SELECT /*+ INDEX (jiveMessage jiveMessage_mDate_idx) */ threadID, " +
        "count(1) AS msgCount FROM jiveMessage, jiveForum WHERE jiveMessage.modifiedDate > ? " +
        "AND jiveMessage.forumID=? AND jiveMessage.forumID=jiveForum.forumID AND " +
        "jiveMessage.modValue >= jiveForum.modMinMsgVal GROUP BY threadID " +
        "ORDER BY msgCount DESC";
     /*
        // Note, the above query includes hints for Oracle, which are necessary
        // so that modified date index will always be used. This is a great
        // tradeoff when the time window you're looking at is not excessively
        // large. MySQL also handles the query very quickly. If your own db
        // needs a hint, you may want to edit the sql logic to add it.
    */

    /**
     * Controls whether extended properties should be lazily loaded (not loaded
     * until requested). If the properties are infrequently used, this provides
     * a great speedup in initial object loading time. However, if your
     * application does use extended properties all the time, you may wish to
     * turn lazy loading off, as it's actually faster in total db lookup time
     * to load everything at once.
     */
    private static final boolean LAZY_PROP_LOADING = true;

    /**
     * Number of ID's per cache block.
     */
    protected static final int BLOCK_SIZE = 400;

    // Constant for an empty bock. This is returned in the case that there are
    // no results when trying to load a thread or message block.
    private static final long[] EMPTY_BLOCK = new long[0];

    // A ResultFilter is used to filter and sort the values that are returned
    // from the threads() and messages() methods. We use a default
    private static final ResultFilter DEFAULT_THREAD_FILTER =
            ResultFilter.createDefaultThreadFilter();
    private static final ResultFilter DEFAULT_MESSAGE_FILTER =
            ResultFilter.createDefaultMessageFilter();

    private static final long serialVersionUID = 01L;

    private long id = -1;
    private long categoryID;
    private String name;
    private String description;
    private java.util.Date creationDate;
    private java.util.Date modifiedDate;
    private int modDefaultThreadValue = 1;
    private int modDefaultMessageValue = 1;
    private int modMinThreadValue = 1 ;
    private int modMinMessageValue = 1;
    private Map properties;

    private transient DbForumFactory factory;
    private transient DbFilterManager filterManager;

    private long [] popularThreads = null;
    // List to keep track of the keys that we insert into global caches.
    // Keeping track of the keys allows us to delete them from the caches
    // as necessary.
    private LinkedList queryKeys = new LinkedList();

    /**
     * Creates a new forum with the specified name and description.
     *
     * @param name the name of the forum.
     * @param description the description of the forum.
     * @param category the ForumCategory the forum is a part of.
     */
    protected DbForum(String name, String description, ForumCategory category) {
        this.id = SequenceManager.nextID(JiveGlobals.FORUM);
        this.categoryID = category.getID();
        this.name = name;
        this.description = description;
        long now = System.currentTimeMillis();
        creationDate = new java.util.Date(now);
        modifiedDate = new java.util.Date(now);
        insertIntoDb(category.getForumCount());
        properties = new Hashtable();
        init();
    }

    /**
     * Loads a forum with the specified id.
     */
    protected DbForum(long id) throws ForumNotFoundException {
        if (id < 0) {
            throw new ForumNotFoundException("ID " + id + " is not valid.");
        }
        this.id = id;
        loadFromDb();
        init();
    }

    private void init() {
        factory = DbForumFactory.getInstance();
        filterManager = new DbFilterManager(this.id, factory);
    }

    private void readObject(java.io.ObjectInputStream in)
            throws IOException, ClassNotFoundException
    {
        in.defaultReadObject();
        init();
    }

    // FROM THE FORUM INTERFACE //

    public long getID() {
        return id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) throws ForumAlreadyExistsException {
        // If the new name is the same as the current name, do nothing.
        if (this.name.equals(name)) {
            return;
        }
        // If a forum with the new name already exists, throw an exception.
        try {
            // Check to make sure that's it's not just a case change. If we
            // don't do this check, the db lookup may give us a false-positive
            // that the name is already in use.
            if (!this.name.toLowerCase().equals(name.toLowerCase())) {
                factory.getForum(name);
                // If we get here, the forum must already exist, so throw exception.
                throw new ForumAlreadyExistsException();
            }
        }
        catch (ForumNotFoundException e) { }

        // Before changing the name of the forum to the new name, we need to
        // remove the old name-to-id mapping.
        factory.cacheManager.forumIDCache.remove(new Long(this.id));

        this.name = name;
        saveToDb();
    }

    public String getDescription() {
        return description;
    }

    public void setDescription(String description) {
        this.description = description;
        saveToDb();
    }

    public java.util.Date getCreationDate() {
        return creationDate;
    }

    public void setCreationDate(java.util.Date creationDate) {
       this.creationDate = creationDate;
       saveToDb();
    }

    public java.util.Date getModifiedDate() {
        return modifiedDate;
    }

    public void setModifiedDate(java.util.Date modifiedDate) {
        this.modifiedDate = modifiedDate;
        saveToDb();
    }

    public int getModerationDefaultThreadValue() {
        return modDefaultThreadValue;
    }

    public void setModerationDefaultThreadValue(int value) {
        this.modDefaultThreadValue = value;
        saveToDb();
    }

    public int getModerationDefaultMessageValue() {
        return modDefaultMessageValue;
    }

    public void setModerationDefaultMessageValue(int value) {
        this.modDefaultMessageValue = value;
        saveToDb();
    }

    public int getModerationMinThreadValue() {
        return modMinThreadValue;
    }

    public void setModerationMinThreadValue(int value) {
        this.modMinThreadValue = value;
        saveToDb();
    }

    public int getModerationMinMessageValue() {
        return modMinMessageValue;
    }

    public void setModerationMinMessageValue(int value) {
        this.modMinMessageValue = value;
        saveToDb();
    }

    public String getProperty(String name) {
        if (LAZY_PROP_LOADING && properties == null) {
            loadPropertiesFromDb();
        }
        return (String)properties.get(name);
    }

    public void setProperty(String name, String value) {
        if (LAZY_PROP_LOADING && properties == null) {
            loadPropertiesFromDb();
        }
        // Make sure the property name and value aren't null.
        if (name == null || value == null || "".equals(name) || "".equals(value)) {
            throw new NullPointerException("Cannot set property with empty or null value.");
        }
        // See if we need to update a property value or insert a new one.
        if (properties.containsKey(name)) {
            // Only update the value in the database if the property value
            // has changed.
            if (!(value.equals(properties.get(name)))) {
                properties.put(name, value);
                updatePropertyInDb(name, value);
                // Re-add forum to cache.
                factory.cacheManager.forumCache.put(new Long(this.id), this);
            }
        }
        else {
            properties.put(name, value);
            insertPropertyIntoDb(name, value);
            // Re-add forum to cache.
            factory.cacheManager.forumCache.put(new Long(this.id), this);
        }
    }

    public void deleteProperty(String name) {
        if (LAZY_PROP_LOADING && properties == null) {
            loadPropertiesFromDb();
        }
        // Only delete the property if it exists.
        if (properties.containsKey(name)) {
            properties.remove(name);
            deletePropertyFromDb(name);
            // Re-add forum to cache.
            factory.cacheManager.forumCache.put(new Long(this.id), this);
        }
    }