dbforumthread.java

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/**
 * $RCSfile: DbForumThread.java,v $
 * $Revision: 1.36 $
 * $Date: 2002/08/06 22:03:42 $
 *
 * 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 java.sql.*;
import java.util.*;
import java.util.Date;
import java.util.LinkedList;
import java.io.IOException;

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

/**
 * Database implementation of the ForumThread interface. It stores thread
 * data in the jiveThread table, and thread properties in jiveThreadProp.
 *
 * @see ForumThread
 */
public class DbForumThread implements ForumThread, Cacheable {

    /** DATABASE QUERIES **/
    private static final String UPDATE_THREAD_MODIFIED_DATE =
        "UPDATE jiveThread SET modifiedDate=? WHERE threadID=?";
    private static final String DELETE_MESSAGE =
        "DELETE FROM jiveMessage WHERE messageID=?";
    private static final String DELETE_MESSAGE_PROPERTIES =
        "DELETE FROM jiveMessageProp WHERE messageID=?";
    private static final String LOAD_THREAD =
        "SELECT forumID, rootMessageID, modValue, rewardPoints, creationDate, " +
        "modifiedDate FROM jiveThread WHERE threadID=?";
    private static final String INSERT_THREAD =
        "INSERT INTO jiveThread(threadID,forumID,rootMessageID,modValue, " +
        "rewardPoints,creationDate,modifiedDate) VALUES(?,?,?,?,?,?,?)";
    private static final String SAVE_THREAD =
        "UPDATE jiveThread SET rootMessageID=?, modValue=?, rewardPoints=?, " +
        "creationDate=?, modifiedDate=? WHERE threadID=?";
    private static final String LOAD_PROPERTIES =
        "SELECT name, propValue FROM jiveThreadProp WHERE threadID=?";
    private static final String INSERT_PROPERTY =
        "INSERT INTO jiveThreadProp(threadID,name,propValue) VALUES(?,?,?)";
    private static final String UPDATE_PROPERTY =
        "UPDATE jiveThreadProp SET propValue=? WHERE name=? AND threadID=?";
    private static final String DELETE_PROPERTY =
        "DELETE FROM jiveThreadProp WHERE threadID=? AND name=?";
    private static final String INSERT_MODERATION_ENTRY =
        "INSERT INTO jiveModeration(objectID, objectType, userID, modDate, " +
        "modValue) VALUES(?,?,?,?,?)";

    /**
     * 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;

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

    // Default filter for messages, called with messages() method.
    private static final ResultFilter DEFAULT_MESSAGE_FILTER =
            ResultFilter.createDefaultMessageFilter();

    private static final long serialVersionUID = 01L;

    private long id = -1;
    private long rootMessageID;
    private java.util.Date creationDate;
    private java.util.Date modifiedDate;
    private DbTreeWalker treeWalker = null;
    // Default the moderation point value to Integer.MIN_VALUE. Then, if the
    // moderation value gets changed before being inserted into the db, we'll know.
    private int moderationValue = Integer.MIN_VALUE;
    private int rewardPoints = 0;
    private Map properties;
    protected long forumID = -1;

    private LinkedList queryKeys = new LinkedList();

    /**
     * Temporarily store a rootMessage object pointer when the thread is being
     * initially created. After creation, the object will remain null.
     */
    private transient ForumMessage rootMessage = null;

    /**
     * Indicates if the object is ready to be saved or not. An object is not
     * ready to be saved if it has just been created and has not yet been added
     * to its container. For example, a message added to a thread, etc.
     */
    private transient boolean readyToSave = false;

    private transient DbForumFactory factory;

    /**
     * Creates a new DbForumThread. The supplied message object is used to
     * derive the name of the thread (subject of message), as well as the
     * creation date and modified date of thread.
     *
     * @param rootMessage the root message of the thread.
     */
    protected DbForumThread(ForumMessage rootMessage) {
        factory = DbForumFactory.getInstance();
        this.id = SequenceManager.nextID(JiveGlobals.THREAD);
        this.rootMessage = rootMessage;
        this.rootMessageID = rootMessage.getID();
        // Set the creation and modified dates to be the same as those of
        // root message.
        long rootMessageTime = rootMessage.getCreationDate().getTime();
        this.creationDate = new java.util.Date(rootMessageTime);
        this.modifiedDate = new java.util.Date(rootMessageTime);
        properties = new Hashtable();
    }

    /**
     * Loads a DbForumThread from the database based on its id.
     *
     * @param id in unique id of the ForumThread to load.
     */
    protected DbForumThread(long id) throws ForumThreadNotFoundException {
        if (id < 0) {
            throw new ForumThreadNotFoundException("ID " + id + " is not valid.");
        }
        factory = DbForumFactory.getInstance();
        this.id = id;
        loadFromDb();
        readyToSave = true;
    }

    private void readObject(java.io.ObjectInputStream in)
            throws IOException, ClassNotFoundException
    {
        in.defaultReadObject();
        readyToSave = true;
        factory = DbForumFactory.getInstance();
    }

    public long getID() {
        return id;
    }

    public String getName() {
        String name = null;
        try {
            name = getMessage(rootMessageID).getSubject();
        }
        catch (Exception e) { }
        return name;
    }

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

    public void setCreationDate(java.util.Date creationDate) {
        this.creationDate = creationDate;
        // Only save to the db if the object is ready
        if (!readyToSave) {
            return;
        }
        saveToDb();
        // Re-add thread to cache.
        factory.cacheManager.threadCache.put(new Long(this.id), this);
    }

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

    public void setModifiedDate(java.util.Date modifiedDate) {
        this.modifiedDate = modifiedDate;
        // Only save to the db if the object is ready
        if (!readyToSave) {
            return;
        }
        saveToDb();
        // Re-add thread to cache.
        factory.cacheManager.threadCache.put(new Long(this.id), this);
    }

    public int getModerationValue() {
        return moderationValue;
    }

    public void setModerationValue(int value, Authorization auth) {
        // If the new value is the same as the old value, return.
        if (moderationValue == value) {
            return;
        }
        setModValue(value, auth);

        // We must also set the moderation value of the root message since
        // the two values must be linked. If the thread is not already added to
        // the database, then we must use the rootMessage object, otherwise
        // we use the getRootMessage() method.
        DbForumMessage message = null;
        if (readyToSave) {
            message = (DbForumMessage)getRootMessage();
        }
        else {
            // The root message object may be a proxy.
            if (rootMessage instanceof ForumMessageProxy) {
                ForumMessageProxy proxyMsg = (ForumMessageProxy)rootMessage;
                try {
                    message = (DbForumMessage)proxyMsg.getProxiedForumMessage();
                }
                catch (UnauthorizedException ue) {
                    // The thread hasn't been added to the db if we're in
                    // this branch of logic, so exception shouldn't happen.
                    ue.printStackTrace();
                }
            }
            // Otherwise, we'll assume it's a DbForumMessage already.
            else {
                message = (DbForumMessage)rootMessage;
            }
        }
        message.setModValue(value, auth);
    }

    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);
                if (readyToSave) {
                    updatePropertyInDb(name, value);
                    // Re-add thread to cache.
                    factory.cacheManager.threadCache.put(new Long(this.id), this);
                    try {
                        factory.cacheManager.getForum(forumID).clearCache();
                    } catch (Exception e) { }
                }
            }
        }
        else {
            properties.put(name, value);
            if (readyToSave) {
                Connection con = null;
                try {
                    con = ConnectionManager.getConnection();
                    insertPropertyIntoDb(name, value, con);
                }
                catch( SQLException sqle ) {
                    sqle.printStackTrace();
                }
                finally {
                    try {  con.close();   }
                    catch (Exception e) { e.printStackTrace(); }
                }
                // Re-add thread to cache.
                factory.cacheManager.threadCache.put(new Long(this.id), this);
                try {
                    factory.cacheManager.getForum(forumID).clearCache();
                } catch (Exception e) { }
            }
        }
    }

    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);
            // Only save to the db if the object is ready
            if (readyToSave) {
                deletePropertyFromDb(name);
                // Update objects in cache.
                factory.cacheManager.threadCache.put(new Long(this.id), this);
                try {
                    factory.cacheManager.getForum(forumID).clearCache();
                } catch (Exception e) { }
            }
        }
    }

    public Iterator propertyNames() {
        if (LAZY_PROP_LOADING && properties == null) {
            loadPropertiesFromDb();
        }
        return Collections.unmodifiableSet(properties.keySet()).iterator();
    }

    public Forum getForum() {
        // If the thread hasn't been added to a forum yet, return null.
        if (forumID == -1) {
            return null;
        }
        try {
            return factory.getForum(forumID);
        }
        catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    public ForumMessage getMessage(long messageID) throws ForumMessageNotFoundException {
        return factory.getMessage(messageID, this.id, forumID);
    }

    public ForumMessage getRootMessage()  {
        ForumMessage rootMessage = null;
        try {
            rootMessage = getMessage(rootMessageID);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        return rootMessage;
    }

    public int getMessageCount() {
        return getMessageCount(DEFAULT_MESSAGE_FILTER);
    }

    public int getMessageCount(ResultFilter resultFilter) {
        String sql = getMessageListSQL(resultFilter, true);
        QueryCacheKey key = new QueryCacheKey(JiveGlobals.THREAD, id, sql, -1);
        return getCount(key);
    }