schemamanager.java

基于Jabber协议的即时消息服务器

/**
 * $Revision$
 * $Date$
 *
 * Copyright (C) 2006 Jive Software. All rights reserved.
 *
 * This software is published under the terms of the GNU Public License (GPL),
 * a copy of which is included in this distribution.
 */

package org.jivesoftware.database;

import org.jivesoftware.util.JiveGlobals;
import org.jivesoftware.util.LocaleUtils;
import org.jivesoftware.util.Log;
import org.jivesoftware.wildfire.XMPPServer;
import org.jivesoftware.wildfire.container.Plugin;
import org.jivesoftware.wildfire.container.PluginManager;

import java.io.*;
import java.sql.*;
import java.util.Arrays;

/**
 * Manages database schemas for Wildfire and Wildfire plugins. The manager uses the
 * jiveVersion database table to figure out which database schema is currently installed
 * and then attempts to automatically apply database schema changes as necessary.<p>
 *
 * Running database schemas automatically requires appropriate database permissions.
 * Without those permissions, the automatic installation/upgrade process will fail
 * and users will be prompted to apply database changes manually.
 *
 * @see DbConnectionManager#getSchemaManager()
 *
 * @author Matt Tucker
 */
public class SchemaManager {

    private static final String CHECK_VERSION_OLD =
            "SELECT minorVersion FROM jiveVersion";
    private static final String CHECK_VERSION =
            "SELECT version FROM jiveVersion WHERE name=?";

    /**
     * Current Wildfire database schema version.
     */
    private static final int DATABASE_VERSION = 10;

    /**
     * Creates a new Schema manager.
     */
    SchemaManager() {

    }

    /**
     * Checks the Wildfire database schema to ensure that it's installed and up to date.
     * If the schema isn't present or up to date, an automatic update will be attempted.
     *
     * @param con a connection to the database.
     * @return true if database schema checked out fine, or was automatically installed
     *      or updated successfully.
     */
    public boolean checkWildfireSchema(Connection con) {
        try {
            return checkSchema(con, "wildfire", DATABASE_VERSION,
                    new ResourceLoader() {
                        public InputStream loadResource(String resourceName) {
                            File file = new File(JiveGlobals.getHomeDirectory() + File.separator +
                                    "resources" + File.separator + "database", resourceName);
                            try {
                                return new FileInputStream(file);
                            }
                            catch (FileNotFoundException e) {
                                return null;
                            }
                        }
                    });
        }
        catch (Exception e) {
            Log.error(LocaleUtils.getLocalizedString("upgrade.database.failure"), e);
            System.out.println(LocaleUtils.getLocalizedString("upgrade.database.failure"));
        }
        return false;
    }

    /**
     * Checks the plugin's database schema (if one is required) to ensure that it's
     * installed and up to date. If the schema isn't present or up to date, an automatic
     * update will be attempted.
     *
     * @param plugin the plugin.
     * @return true if database schema checked out fine, or was automatically installed
     *      or updated successfully, or if it isn't needed. False will only be returned
     *      if there is an error.
     */
    public boolean checkPluginSchema(final Plugin plugin) {
        final PluginManager pluginManager = XMPPServer.getInstance().getPluginManager();
        String schemaKey = pluginManager.getDatabaseKey(plugin);
        int schemaVersion = pluginManager.getDatabaseVersion(plugin);
        // If the schema key or database version aren't defined, then the plugin doesn't
        // need database tables.
        if (schemaKey == null || schemaVersion == -1) {
            return true;
        }
        Connection con = null;
        try {
            con = DbConnectionManager.getConnection();
            return checkSchema(con, schemaKey, schemaVersion, new ResourceLoader() {
                public InputStream loadResource(String resourceName) {
                    File file = new File(pluginManager.getPluginDirectory(plugin) +
                            File.separator + "database", resourceName);
                    try {
                        return new FileInputStream(file);
                    }
                    catch (FileNotFoundException e) {
                        return null;
                    }
                }
            });
        }
        catch (Exception e) {
            Log.error(LocaleUtils.getLocalizedString("upgrade.database.failure"), e);
            System.out.println(LocaleUtils.getLocalizedString("upgrade.database.failure"));
        }
        finally {
            DbConnectionManager.closeConnection(con);
        }
        return false;
    }

    /**
     * Checks to see if the database needs to be upgraded. This method should be
     * called once every time the application starts up.
     *
     * @param con the database connection to use to check the schema with.
     * @param schemaKey the database schema key (name).
     * @param requiredVersion the version that the schema should be at.
     * @param resourceLoader a resource loader that knows how to load schema files.
     * @throws Exception if an error occured.
     */
    private boolean checkSchema(Connection con, String schemaKey, int requiredVersion,
            ResourceLoader resourceLoader) throws Exception
    {
        int currentVersion = -1;
        PreparedStatement pstmt = null;
        ResultSet rs = null;
        try {
            pstmt = con.prepareStatement(CHECK_VERSION);
            pstmt.setString(1, schemaKey);
            rs = pstmt.executeQuery();
            if (rs.next()) {
                currentVersion = rs.getInt(1);
            }
        }
        catch (SQLException sqle) {
            DbConnectionManager.closeResultSet(rs);
            DbConnectionManager.closeStatement(pstmt);
            // Releases of Wildfire before 2.6.0 stored a major and minor version
            // number so the normal check for version can fail. Check for the
            // version using the old format in that case.
            if (schemaKey.equals("wildfire")) {
                try {
                    if (pstmt != null) {
                        pstmt.close();
                    }
                    pstmt = con.prepareStatement(CHECK_VERSION_OLD);
                    rs = pstmt.executeQuery();
                    if (rs.next()) {
                        currentVersion = rs.getInt(1);
                    }
                }
                catch (SQLException sqle2) {
                    // The database schema must not be installed.
                    Log.debug("Error verifying server version", sqle2);
                }
            }
        }
        finally {
            DbConnectionManager.closeResultSet(rs);
            DbConnectionManager.closeStatement(pstmt);
        }
        // If already up to date, return.
        if (currentVersion == requiredVersion) {
            return true;
        }
        // If the database schema isn't installed at all, we need to install it.
        else if (currentVersion == -1) {