newsgroupimporter.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 421 行

/**
 * $RCSfile: NewsgroupImporter.java,v $
 * $Revision: 1.5 $
 * $Date: 2002/07/16 15:35:18 $
 *
 * 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.gateway;

import com.jivesoftware.forum.Forum;
import com.jivesoftware.forum.ForumFactory;
import com.jivesoftware.forum.ForumNotFoundException;
import com.jivesoftware.forum.UnauthorizedException;
import dog.mail.nntp.NNTPStore;

import javax.mail.*;
import java.text.SimpleDateFormat;
import java.util.*;

/**
 * A gateway for the import of messages from a newsgroup.
 *
 * @author Bruce Ritchie
 */
public class NewsgroupImporter implements GatewayImporter {

    private NNTPGateway gateway;
    private int lastMessageNumberSeen = -1;

    /**
     * Used to flag messages in the forum with a message id
     * specific to this gateway.
     */
    public static final String GATEWAY_MESSAGE_ID = "NNTP-Message-ID";

    /**
     * Used to flag messages in the forum with a parent id
     * specific to this gateway.
     */
    public static final String GATEWAY_PARENT_ID = "NNTP-Parent-ID";

    /**
     * Used for defining for the NNTP gateway from when to do the import.
     */
    private static final SimpleDateFormat DATEFORMATTER =
            new SimpleDateFormat("yyyy.MM.dd hh:mm:ss");

    private static Map forumLock = Collections.synchronizedMap(new HashMap());

    /**
     * Create an instance
     */
    public NewsgroupImporter(ForumFactory factory, Forum forum) {
        gateway = new NNTPGateway(factory, forum);

        synchronized(forumLock) {
            if (forumLock.get(new Long(gateway.forumID)) == null) {
                forumLock.put(new Long(gateway.forumID), new Long(gateway.forumID));
            }
        }
    }

    //FROM THE GATEWAYIMPORTER INTERFACE//

    public void importData(Date afterDate) throws GatewayException
    {
        synchronized (forumLock.get(new Long(gateway.forumID))) {
            gateway.importData(afterDate);
        }
    }

    public void stop()
            throws GatewayException
    {
        gateway.stop();
    }

    //GATEWAY PROPERTIES//

    /**
     * Retrieves the username set for this gateway. Default is null.
     *
     * @return username the username to be used in connecting to the NNTP server.
     */
    public String getUsername() {
        return gateway.getUsername();
    }

    /**
     * Sets the username to be used in connecting to the NNTP server.
     *
     * @param username the username to be used in connecting to the NNTP server.
     */
    public void setUsername(String username) {
        if ("".equals(username)) {
            username = null;
        }
        gateway.setUsername(username);
    }

    /**
     * Retrieves the password to be used in connecting to the NNTP server.
     * Default is null.
     *
     * @return the password to be used in connecting to the NNTP server.
     */
    public String getPassword() {
        return gateway.getPassword();
    }

    /**
     * Sets the password to be used in connecting to the NNTP server.
     *
     * @param password the password to use be used in connecting to the
     *        NNTP server.
     */
    public void setPassword(String password) {
        if ("".equals(password)) {
            password = null;
        }
        gateway.setPassword(password);
    }

    /**
     * Returns the port number that will be used when connecting to the NNTP
     * server. The default is 119, the standard NNTP port number.
     *
     * @return the port number that will be used when connecting to the NNTP
     *         server.
     */
    public int getPort() {
        return gateway.getPort();
    }

    /**
     * Set the port to use when connecting to the NNTP server. The default is
     * port 119; for ssl the normal port to use is 993.
     *
     * @param port the port to use when connecting to the NNTP server. The
     *        default is port 119.
     */
    public void setPort(int port) {
        gateway.setPort(port);

        // Old session no longer valid so set to null.
        gateway.session = null;
    }

    /**
     * Returns the NNTP host (eg news.example.com). The host is null by
     * default, but must be set before gateway imports can execute.
     *
     * @return the NNTP host (eg news.example.com).
     */
    public String getHost() {
        return gateway.getHost();
    }

    /**
     * Sets the NNTP host (eg news.example.com). The host is null by
     * default, but must be set before gateway imports can execute.
     *
     * @param host the NNTP host (eg news.example.com) to use.
     */
    public void setHost(String host) {
        gateway.setHost(host);

        // Old session no longer valid so set to null.
        gateway.session = null;
    }

    /**
     * Retrieves the newsgroup that the gateway is going to use.
     *
     * @return the newsgroup that the gateway will use.
     */
    public String getNewsgroup() {
        return gateway.getMailbox();
    }

    /**
     * Sets the newsgroup that this gateway is going to use.
     *
     * @param newsgroup the newsgroup the gateway is going to use.
     */
    public void setNewsgroup(String newsgroup) {
        gateway.setMailbox(newsgroup);

        // Old session no longer valid so set to null.
        gateway.session = null;
    }

    /**
     * Returns the body that will be used when creating temporary parent
     * messages. It's possible with email accounts and mailing
     * lists to get a response to a message before getting the original message.
     * If this happens and only the child message is available at the time of
     * the gateway import, Jive must still have a way to establish a correct
     * parent/child relationship. Therefore, a temporary fake parent message is
     * created using an extrapolated subject from the child, and a body with the
     * value <tt>temporaryParentBody</tt>. By default, this value will be
     * the empty String. However, you may wish to create a short message that
     * explains the nature of the fake parent message to the user.<p>
     *
     * On subsequent imports when a real parent message is found, the fake
     * data will be replaced with the correct subject and body.<p>
     *
     * @return the message body that will be used for temporary fake parent
     *      messages.
     */
    public String getTemporaryParentBody() {
        return gateway.getTemporaryParentBody();
    }

    /**
     * Sets the body that will be used when creating temporary parent
     * messages. It's possible with email accounts and mailing
     * lists to get a response to a message before getting the original message.
     * If this happens and only the child message is available at the time of
     * the gateway import, Jive must still have a way to establish a correct
     * parent/child relationship. Therefore, a temporary fake parent message is
     * created using an extrapolated subject from the child, and a body with the
     * value <tt>temporaryParentBody</tt>. By default, this value will be
     * the empty String. However, you may wish to create a short message that
     * explains the nature of the fake parent message to the user.<p>
     *
     * On subsequent imports when a real parent message is found, the fake
     * data will be replaced with the correct subject and body.<p>
     *
     * @param temporaryParentBody the message body that will be used for
     *      temporary fake parent messages.
     */
    public void setTemporaryParentBody(String temporaryParentBody) {
        gateway.setTemporaryParentBody(temporaryParentBody);
    }

    /**
     * Returns true if debugging is turned on for the NNTP transport layer.
     * Debug information is written to <tt>System.out.err</tt>.
     *
     * @return true if NNTP debugging is turned on, false otherwise.
     */
    public boolean isDebugEnabled() {
        return gateway.isDebugEnabled();
    }

    /**
     * Toggles NNTP transport layer debugging on or off. Debug information is
     * written to <tt>System.out<p>
     *
     * @param debugEnabled true if NNTP debugging should be enabled, false otherwise.
     */
    public void setDebugEnabled(boolean debugEnabled) {
        gateway.setDebugEnabled(debugEnabled);

        // Old session no longer valid so set to null.
        gateway.session = null;
    }

    /**
     * Used by the gateway to keep track of the last message seen.
     * This allows for fast updates since we can ask the NNTP
     * server for only the messages newer than the message associated
     * with this message number.<p>
     *
     * It is *highly* recommended not to set this yourself.
     *
     * @param messageNumber the last message number seen by this gateway.
     */
    public void setLastMessageNumberSeen(int messageNumber) {
        if (messageNumber > 0) {
            lastMessageNumberSeen = messageNumber;
        }
    }

    /**
     * Used by the gateway to keep track of the last message seen.
     * This allows for fast updates since we can ask the NNTP
     * server for only the messages newer than the message associated
     * with this message number.<p>
     *
     * It is *highly* recommended not to set this but rather let the
     * gateway handle it itself.
     *
     * @return the last message number seen by this gateway.
     */
    public int getLastMessageNumberSeen() {
        return lastMessageNumberSeen;
    }

    /**
     * By default attachments are allowed by this gateway.
     *
     * @return whether this gateway will allow attachments or not.
     */
    public boolean isAttachmentsEnabled() {
        return gateway.isAttachmentsEnabled();
    }

    /**
     * Sets whether this gateway allows the import of attachments or not.
     * If true attachments are allowed, otherwise attachments will be
     * stripped before importing a message.
     *
     * @param attachmentsEnabled true is attachments are allowed,
     *        false otherwise.
     */
    public void setAttachmentsEnabled(boolean attachmentsEnabled) {
        gateway.setAttachmentsEnabled(attachmentsEnabled);
    }

    /**
     * Returns whether parentage checks will be done using subject line matching or not.
     *
     * @return whether parentage checks will be done using subject line matching or not.
     */
    public boolean isSubjectParentageCheckEnabled() {
        return gateway.subjectParentageCheckEnabled;
    }

    /**
     * Sets whether parentage checks will be done using subject line matching or not.
     *
     * @param subjectParentageCheckEnabled true if parentage checks will be done using
     * subject line matching, false otherwise.
     */
    public void setSubjectParentageCheckEnabled(boolean subjectParentageCheckEnabled) {
        gateway.subjectParentageCheckEnabled = subjectParentageCheckEnabled;
    }

    /**
     * An extension of the JavaMailGateway class
     */
    private class NNTPGateway extends JavaMailGateway {

        protected Session session = null;

        public NNTPGateway(ForumFactory factory, Forum forum) {
            super(factory, forum);
            this.setPort(119); // use the default port of 119
            setProtocol("nntp");

            gatewayMessageId = GATEWAY_MESSAGE_ID;
            gatewayParentId  = GATEWAY_PARENT_ID;
        }

        /**
         * Override base class to set a system property and then
         * get the JavaMail store.
         *
         * @param afterDate the date after which we'll import a message.
         * @return Store a connected store object.
         * @throws MessagingException if error occurred establishing the connection.
         */
        protected Store getStore(Date afterDate) throws MessagingException {
            if (afterDate == null) {
                afterDate = new Date(0L);
            }

            Properties props = new Properties();
            props.put("mail.nntp.useNewNews", "false");
            props.put("mail.nntp.SimpleDateFormat", DATEFORMATTER.toPattern());
            props.put("mail.nntp.afterDate", DATEFORMATTER.format(afterDate));
            props.put("mail.nntp.memoryOptimisation", Boolean.TRUE.toString());
            props.put("mail.nntp.checkNewTimeout", "10");
            props.put("mail.store.protocol", "nntp");
            props.put("mail.transport.protocol", "nntp-post");
            if (lastMessageNumberSeen > 0) {
                props.put("mail.nntp.lastArticleIdSeen", String.valueOf(lastMessageNumberSeen));
            }

            URLName url = new URLName(protocol, host, port, mailbox, username, password);

            session = Session.getInstance(props, null);
            session.setDebug(debugEnabled);
            Store store = new NNTPStore(session, url);
            store.connect();

            return store;
        }

        /**
         * Overridden so that we can grab the article number from the provider.
         */
        protected String getMessageID(Message message) throws MessagingException {
            if (message.getMessageNumber() > 0) {
                int messageNumber = message.getMessageNumber();
                if (messageNumber != lastMessageNumberSeen) {
                    lastMessageNumberSeen = messageNumber;
                }
            }

            return super.getMessageID(message);
        }

        /**
         * Overridden so that we save the latest article number for the next
         * run.
         */
        protected void cleanup() {
            try {
                GatewayManager gatewayManager = factory.getForum(forumID).getGatewayManager();

                for (int i=0; i < gatewayManager.getGatewayCount(); i++) {
                    GatewayImporter gateway = gatewayManager.getGateway(i).getGatewayImporter();
                    if (gateway != null && gateway instanceof NewsgroupImporter) {
                        ((NewsgroupImporter) gateway).setLastMessageNumberSeen(lastMessageNumberSeen);
                    }
                }

                gatewayManager.saveGateways(false);
            }
            catch (ForumNotFoundException e) { /* do nothing */ }
            catch (UnauthorizedException e) { /* do nothing */ }
        }
    }
}