dbforummessage.java

来自「Jive是基于JSP/JAVA技术构架的一个大型BBS论坛系统,这是Jive论坛」· Java 代码 · 共 1,052 行 · 第 1/3 页

/**
 * $RCSfile: DbForumMessage.java,v $
 * $Revision: 1.19 $
 * $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.sql.*;
import java.util.*;
import java.io.*;

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

/**
 * Database implementation of the ForumMessage interface. It stores messages
 * in the jiveMessage database table, and message properties in JiveMessageProp
 * table.<p>
 *
 * Messages are not inserted into the database until they are added
 * to a thread. Therefore, it is best to set all properties of the message
 * before adding it to a thread in order to avoid extra database operations.<p>
 *
 * One key feature of the Jive message architecture is the ability to apply
 * dynamic filters to messages (specified at the global and forum level).
 * However, computing the filtered value of a message can be fairly expensive.
 *
 * @author Matt Tucker
 */
public final class DbForumMessage implements ForumMessage, Cacheable {

    /** DATABASE QUERIES **/
    private static final String LOAD_ATTACHMENTS =
        "SELECT attachmentID FROM jiveAttachment WHERE messageID=?";
    private static final String LOAD_PROPERTIES =
        "SELECT name, propValue FROM jiveMessageProp WHERE messageID=?";
    private static final String INSERT_PROPERTY =
        "INSERT INTO jiveMessageProp(messageID,name,propValue) VALUES(?,?,?)";
    private static final String UPDATE_PROPERTY =
        "UPDATE jiveMessageProp SET propValue=? WHERE name=? AND messageID=?";
    private static final String DELETE_PROPERTY =
        "DELETE FROM jiveMessageProp WHERE messageID=? AND name=?";
    private static final String LOAD_MESSAGE =
        "SELECT threadID, forumID, userID, subject, body, modValue, rewardPoints, "+
        "creationDate, modifiedDate FROM jiveMessage WHERE messageID=?";
    private static final String INSERT_MESSAGE =
        "INSERT INTO jiveMessage(messageID, parentMessageID, threadID, forumID, " +
        "userID, subject, body, modValue, rewardPoints, creationDate, modifiedDate) " +
        "VALUES(?,?,?,?,?,?,?,?,?,?,?)";
    private static final String UPDATE_PARENT_ID =
        "UPDATE jiveMessage SET parentMessageID=? WHERE messageID=?";
    private static final String SAVE_MESSAGE =
        "UPDATE jiveMessage SET subject=?, body=?, modValue=?, " +
        "rewardPoints=?, creationDate=?, modifiedDate=? WHERE messageID=?";
    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.
     *
     * NOTE: lazy loading turned off by default for now since new filter
     * caching code always calls properties. This may be optimized in the
     * future so that lazy property loading makes sense again.
     */
    private static final boolean LAZY_PROP_LOADING = false;

    private static final long serialVersionUID = 01L;

    private long id = -1;
    private java.util.Date creationDate;
    private java.util.Date modifiedDate;
    private String subject = "";
    private String body = "";
    private long userID;
    protected long threadID = -1;
    protected long forumID = -1;
    // 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.
    protected int moderationValue = Integer.MIN_VALUE;
    private int rewardPoints = 0;
    private Map properties = null;

    private long [] attachmentIDs;

    // Variables to hold filtered values.
    protected transient boolean filtersCached = false;
    protected transient String filteredSubject = null;
    protected transient String filteredBody = null;
    protected transient Map filteredProperties = null;

    private transient DbForumFactory factory;

    /**
     * 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.
     */
    protected transient boolean readyToSave = false;

    /**
     * Creates a new DbForumMessage object. If the User object is null, we'll
     * assume that the message has an anonymous author.
     */
    protected DbForumMessage(User user) {
        if (user != null) {
            this.userID = user.getID();
        }
        else {
            this.userID = -1;
        }

        this.id = SequenceManager.nextID(JiveGlobals.MESSAGE);
        long now = System.currentTimeMillis();
        creationDate = new java.util.Date(now);
        modifiedDate = new java.util.Date(now);
        properties = new Hashtable();
        factory = DbForumFactory.getInstance();
    }

    /**
     * Loads the specified DbForumMessage by its message id.
     */
    protected DbForumMessage(long id) throws ForumMessageNotFoundException {
        if (id < 0) {
            throw new ForumMessageNotFoundException("ID " + id + " is not valid.");
        }
        this.id = id;
        loadFromDb();
        readyToSave = true;
        factory = DbForumFactory.getInstance();
    }

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

    //FROM THE FORUMMESSAGE INTERFACE//

    public long getID() {
        return id;
    }

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

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

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

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

    public String getSubject() {
        // Return cached filter value if it exists.
        if (filteredSubject != null) {
            return filteredSubject;
        }
        // Otherwise, return normal value.
        else {
            return subject;
        }
    }

    public String getUnfilteredSubject() {
        return subject;
    }

    public void setSubject(String subject) throws UnauthorizedException {
        this.subject = subject;
        // Only save to the db if the object is read
        if (!readyToSave) {
            return;
        }
        // Update modifiedDate to the current time.
        modifiedDate.setTime(System.currentTimeMillis());
        saveToDb();
        // Reset the cached filter output.
        filtersCached = false;
        filteredSubject = null;
        filteredBody = null;
        filteredProperties = null;
        // Re-add message to cache.
        factory.cacheManager.messageCache.put(new Long(this.id), this);
    }

    public String getBody() {
        // Return cached filter value if it exists.
        if (filteredBody != null) {
            return filteredBody;
        }
        // Otherwise, return normal value.
        else {
            return body;
        }
    }

    public String getUnfilteredBody() {
        return body;
    }

    public void setBody(String body) throws UnauthorizedException {
        this.body = body;
        // Only save to the db if the object is read
        if (!readyToSave) {
            return;
        }
        // Update modifiedDate to the current time.
        modifiedDate.setTime(System.currentTimeMillis());
        saveToDb();
        // Reset the cached filter output.
        filtersCached = false;
        filteredSubject = null;
        filteredBody = null;
        filteredProperties = null;
        // Re-add message to cache.
        factory.cacheManager.messageCache.put(new Long(this.id), this);
    }

    public User getUser() {
        if (userID == -1) {
            return null;
        }
        User user = null;
        try {
            user = factory.getUserManager().getUser(userID);
        }
        catch (UserNotFoundException unfe) {
            unfe.printStackTrace();
        }
        return user;
    }

    public Attachment createAttachment(String name, String contentType,
            InputStream data) throws IllegalStateException, AttachmentException
    {
        // If the message has not yet been added to a thread, don't allow
        // attachment to be created.
        if (this.threadID == -1) {
            throw new IllegalStateException("Cannot create an attachment before " +
                "message is added to a thread.");
        }

        AttachmentManager attachmentManager = factory.getAttachmentManager();
        // See if we're allowed to add another attachment.

        if (getAttachmentCount() > attachmentManager.getMaxAttachmentsPerMessage()) {
            throw new AttachmentException(AttachmentException.TOO_MANY_ATTACHMENTS);
        }

        DbAttachment attachment = new DbAttachment(id, name, contentType, data);
        this.attachmentIDs = null;
        // Re-add object to cache.
        factory.cacheManager.messageCache.put(new Long(id), this);
        return attachment;
    }

    public int getAttachmentCount() {
        if (attachmentIDs == null) {
            // load the attachment ID's
            attachments();
        }
        return attachmentIDs.length;
    }

    public void deleteAttachment(Attachment attachment) throws AttachmentException {
        // See if the attachment belongs to this message.
        DbAttachment dbAttachment = (DbAttachment)attachment;
        if (dbAttachment.getMessageID() != this.id) {
            throw new IllegalArgumentException("Attachment does not belong " +
                "to message.");
        }
        Connection con = null;
        try {
            con = ConnectionManager.getConnection();
            dbAttachment.delete(con);
            this.attachmentIDs = null;
            // Re-add object to cache.
            factory.cacheManager.messageCache.put(new Long(id), this);
        }
        catch (Exception e) {
            throw new AttachmentException(AttachmentException.GENERAL_ERROR, e);
        }
        finally {
            try {  con.close();   }
            catch (Exception e) { e.printStackTrace(); }
        }
    }

    public Iterator attachments() {
        if (attachmentIDs == null) {
            LongList attachments = new LongList();
            Connection con = null;
            PreparedStatement pstmt = null;
            try {
                con = ConnectionManager.getConnection();
                pstmt = con.prepareStatement(LOAD_ATTACHMENTS);
                pstmt.setLong(1,  this.id);
                ResultSet rs = pstmt.executeQuery();
                while (rs.next()) {
                    attachments.add(rs.getLong(1));
                }
                this.attachmentIDs = attachments.toArray();
                // Re-add object to cache.
                factory.cacheManager.messageCache.put(new Long(id), this);
            }
            catch(SQLException sqle) {
                sqle.printStackTrace();
            }
            finally {
                try {  pstmt.close();   }
                catch (Exception e) { e.printStackTrace(); }