/*
 * #%L
 * Netarchivesuite - harvester
 * %%
 * Copyright (C) 2005 - 2014 The Royal Danish Library, the Danish State and University Library,
 *             the National Library of France and the Austrian National Library.
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 2.1 of the
 * License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Lesser Public License for more details.
 * 
 * You should have received a copy of the GNU General Lesser Public
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/lgpl-2.1.html>.
 * #L%
 */

package dk.netarkivet.harvester.datamodel;

import java.sql.Connection;
import java.sql.SQLException;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import dk.netarkivet.common.CommonSettings;
import dk.netarkivet.common.exceptions.ArgumentNotValid;
import dk.netarkivet.common.exceptions.IOFailure;
import dk.netarkivet.common.exceptions.IllegalState;
import dk.netarkivet.common.exceptions.NotImplementedException;
import dk.netarkivet.common.utils.DBUtils;
import dk.netarkivet.common.utils.SettingsFactory;

/**
 * Defines database specific implementations used by the Harvester.
 * <p>
 * The actual actual implementation which is loaded is defined by the {@link CommonSettings#DB_SPECIFICS_CLASS} setting.
 * See the sub class list for available implementations
 */
public abstract class DBSpecifics extends SettingsFactory<DBSpecifics> {

    /** The instance of the DBSpecifics class. */
    private static DBSpecifics instance;

    private static final Logger log = LoggerFactory.getLogger(DBSpecifics.class);

    /**
     * Get the singleton instance of the DBSpecifics implementation class.
     *
     * @return An instance of DBSpecifics with implementations for a given DB.
     */
    public static synchronized DBSpecifics getInstance() {
        if (instance == null) {
            instance = getInstance(CommonSettings.DB_SPECIFICS_CLASS);
        }
        return instance;
    }

    /**
     * Get a temporary table for short-time use. The table should be disposed of with dropTemporaryTable. The table has
     * two columns domain_name varchar(Constants.MAX_NAME_SIZE) + config_name varchar(Constants.MAX_NAME_SIZE) All rows
     * in the table must be deleted at commit or rollback.
     *
     * @param c The DB connection to use.
     * @return The name of the created table
     * @throws SQLException if there is a problem getting the table.
     */
    public abstract String getJobConfigsTmpTable(Connection c) throws SQLException;

    /**
     * Dispose of a temporary table gotten with getTemporaryTable. This can be expected to be called from within a
     * finally clause, so it mustn't throw exceptions.
     *
     * @param c The DB connection to use.
     * @param tableName The name of the temporarily created table.
     */
    public abstract void dropJobConfigsTmpTable(Connection c, String tableName);

    /**
     * Get the name of the JDBC driver class that handles interfacing to this server.
     *
     * @return The name of a JDBC driver class
     */
    public abstract String getDriverClassName();

    /**
     * Update a table to a newer version, if necessary. This will check the schemaversions table to see the current
     * version and perform a table-specific update if required.
     *
     * @param tableName The table to update
     * @param toVersion The version to update the table to.
     * @throws IllegalState If the table is an unsupported version, and the toVersion is less than the current version
     * of the table
     * @throws NotImplementedException If no method exists for migration from current version of the table to the
     * toVersion of the table.
     * @throws IOFailure in case of problems in interacting with the database
     */

    public synchronized void updateTable(String tableName, int toVersion) {
        ArgumentNotValid.checkNotNullOrEmpty(tableName, "String tableName");
        ArgumentNotValid.checkPositive(toVersion, "int toVersion");

        Connection c = HarvestDBConnection.get();
        int currentVersion = -1;
        try {
            currentVersion = DBUtils.getTableVersion(c, tableName);
        } finally {
            HarvestDBConnection.release(c);
        }
        if (currentVersion == toVersion) {
            // Nothing to do. Version of table is already correct.
            return;
        }
        log.info("Trying to migrate table '" + tableName + "' from version '" + currentVersion + "' to version '"
                + toVersion + "'.");

        if (currentVersion > toVersion) {
            throw new IllegalState("Database is in an illegalState: The current version of table '" + tableName
                    + "' is not acceptable (current version is greater than requested version).");
        }

        if (tableName.equals(HarvesterDatabaseTables.JOBS.getTablename())) {
            upgradeJobsTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.FULLHARVESTS.getTablename())) {
            upgradeFullharvestsTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.CONFIGURATIONS.getTablename())) {
            upgradeConfigurationsTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.GLOBALCRAWLERTRAPLISTS.getTablename())) {
            upgradeGlobalcrawlertraplistsTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.GLOBALCRAWLERTRAPEXPRESSIONS.getTablename())) {
            upgradeGlobalcrawlertrapexpressionsTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.RUNNINGJOBSHISTORY.getTablename())) {
            upgradeRunningjobshistoryTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.RUNNINGJOBSMONITOR.getTablename())) {
            upgradeRunningjobsmonitor(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.FRONTIERREPORTMONITOR.getTablename())) {
            upgradeFrontierreportmonitorTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.EXTENDEDFIELD.getTablename())) {
            upgradeExtendedFieldTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.EXTENDEDFIELDVALUE.getTablename())) {
            upgradeExtendedFieldValueTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.EXTENDEDFIELDTYPE.getTablename())) {
            upgradeExtendedFieldTypeTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.DOMAINS.getTablename())) {
            upgradeDomainsTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.HARVESTDEFINITIONS.getTablename())) {
            upgradeHarvestdefinitionsTable(currentVersion, toVersion);
        } else if (tableName.equals(HarvesterDatabaseTables.HARVESTCHANNELS.getTablename())) {
            upgradeHarvestchannelTable(currentVersion, toVersion);
            // Add new if else when other tables need to be upgraded
        } else {
            throw new NotImplementedException("No method exists for migrating table '" + tableName + "' to version "
                    + toVersion);
        }
    }

    private void upgradeHarvestdefinitionsTable(int currentVersion, int toVersion) {
        if (currentVersion < 2) {
            throw new IllegalState("Database is in an illegalState: The current version " + currentVersion
                    + " of table '" + HarvesterDatabaseTables.HARVESTDEFINITIONS.getTablename()
                    + "' is not acceptable. The current table version is less than open source version 2. "
                    + "Probably a wrong entry in the schemaversions table");
        }
        if (currentVersion == 2 && toVersion >= 3) {
            migrateHarvestdefinitionsv2tov3();
            currentVersion = 3;
        }
        if (currentVersion == 3 && toVersion >= 4) {
            migrateHarvestdefinitionsv3tov4();
            currentVersion = 4;
        }
        // insert new migrations here
        if (currentVersion != HarvesterDatabaseTables.HARVESTDEFINITIONS.getRequiredVersion()) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.HARVESTDEFINITIONS.getTablename() + "' from version " + currentVersion
                    + " to version " + toVersion);
        }

    }

    private void upgradeExtendedFieldTypeTable(int currentVersion, int toVersion) {
        if (currentVersion == 0 && toVersion >= 1) {
            createExtendedFieldTypeTable();
            currentVersion = 1;
        }
        if (currentVersion > HarvesterDatabaseTables.EXTENDEDFIELDTYPE.getRequiredVersion()) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.EXTENDEDFIELDTYPE.getTablename() + "' from version " + currentVersion
                    + " to version " + toVersion);
        }
    }

    private void upgradeExtendedFieldValueTable(int currentVersion, int toVersion) {
        if (currentVersion == 0 && toVersion >= 1) {
            createExtendedFieldValueTable();
            currentVersion = 1;
        }
        if (currentVersion == 1 && toVersion >= 2) {
            migrateExtendedFieldTableValueV1toV2();
            currentVersion = 2;
        }

        if (currentVersion > HarvesterDatabaseTables.EXTENDEDFIELDVALUE.getRequiredVersion()) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.EXTENDEDFIELDVALUE.getTablename() + "' from version " + currentVersion
                    + " to version " + toVersion);
        }
    }

    private void upgradeExtendedFieldTable(int currentVersion, int toVersion) {
        if (currentVersion == 0 && toVersion >= 1) {
            createExtendedFieldTable();
            currentVersion = 1;
        }
        if (currentVersion == 1 && toVersion >= 2) {
            migrateExtendedFieldTableV1toV2();
            currentVersion = 2;
        }
        if (currentVersion > HarvesterDatabaseTables.EXTENDEDFIELD.getRequiredVersion()) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.EXTENDEDFIELD.getTablename() + "' from version " + currentVersion
                    + " to version " + toVersion);
        }
    }

    /**
     * Migrate the frontierreportmonitor table.
     *
     * @param currentVersion the current version of the frontierreportmonitor table
     * @param toVersion the required version of the frontierreportmonitor table
     */
    private void upgradeFrontierreportmonitorTable(int currentVersion, int toVersion) {
        if (currentVersion == 0 && toVersion == 1) {
            createFrontierReportMonitorTable();
            currentVersion = 1;
        }
        // insert new migrations here
        if (currentVersion > HarvesterDatabaseTables.FRONTIERREPORTMONITOR.getRequiredVersion()) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.FRONTIERREPORTMONITOR.getTablename() + "' from version " + currentVersion
                    + " to version " + toVersion);
        }
    }

    /**
     * Migrate the runningjobsmonitor table.
     *
     * @param currentVersion the current version of the runningjobsmonitor table
     * @param toVersion the required version of the runningjobsmonitor table
     */
    private void upgradeRunningjobsmonitor(int currentVersion, int toVersion) {
        if (currentVersion == 0 && toVersion >= 1) {
            createRunningJobsMonitorTable();
            currentVersion = 1;
        }
        if (currentVersion == 1 && toVersion >= 2) {
            migrateRunningJobsMonitorTableV1ToV2();
            currentVersion = 2;
        }
        if (currentVersion > HarvesterDatabaseTables.RUNNINGJOBSMONITOR.getRequiredVersion()) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.RUNNINGJOBSMONITOR.getTablename() + "' from version " + currentVersion
                    + " to version " + toVersion);
        }
    }

    /**
     * Migrate the runningjobshistory table.
     *
     * @param currentVersion the current version of the runningjobshistory table
     * @param toVersion The required version of the runningjobshistory table
     */
    private void upgradeRunningjobshistoryTable(int currentVersion, int toVersion) {
        if (currentVersion == 0 && toVersion >= 1) {
            createRunningJobsHistoryTable();
            currentVersion = 1;
        }
        if (currentVersion == 1 && toVersion >= 2) {
            migrateRunningJobsHistoryTableV1ToV2();
            currentVersion = 2;
        }
        // insert new migrations here
        if (currentVersion > HarvesterDatabaseTables.RUNNINGJOBSHISTORY.getRequiredVersion()) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.RUNNINGJOBSHISTORY.getTablename() + "' from version " + currentVersion
                    + " to version " + toVersion);
        }

    }

    /**
     * Migrate the globalecrawlertrapexpressions table.
     *
     * @param currentVersion the current version of the jobs table
     * @param toVersion The required version of the jobs table
     */
    private void upgradeGlobalcrawlertrapexpressionsTable(int currentVersion, int toVersion) {
        if (currentVersion == 0 && toVersion >= 1) {
            createGlobalCrawlerTrapExpressions();
            currentVersion = 1;
        }
        // insert new migrations here
        if (currentVersion > HarvesterDatabaseTables.GLOBALCRAWLERTRAPEXPRESSIONS.getRequiredVersion()) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.GLOBALCRAWLERTRAPEXPRESSIONS.getTablename() + "' from version "
                    + currentVersion + " to version " + toVersion);
        }

    }

    /**
     * Migrate the globalecrawlertraplists table.
     *
     * @param currentVersion the current version of the globalecrawlertraplists table
     * @param toVersion The required version of the globalecrawlertraplists table
     */
    private void upgradeGlobalcrawlertraplistsTable(int currentVersion, int toVersion) {
        if (currentVersion == 0 && toVersion >= 1) {
            createGlobalCrawlerTrapLists();
            currentVersion = 1;
        }
        // insert new migrations here
        if (currentVersion > HarvesterDatabaseTables.GLOBALCRAWLERTRAPLISTS.getRequiredVersion()) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.GLOBALCRAWLERTRAPLISTS.getTablename() + "' from version "
                    + currentVersion + " to version " + toVersion);
        }

    }

    /**
     * Migrate the jobs table.
     *
     * @param currentVersion the current version of the jobs table
     * @param toVersion The required version of the jobs table
     */
    private void upgradeJobsTable(int currentVersion, int toVersion) {
        if (currentVersion < 3) {
            throw new IllegalState("Database is in an illegalState: " + "The current version " + currentVersion
                    + " of table '" + HarvesterDatabaseTables.JOBS.getTablename() + "' is not acceptable. "
                    + "(current version is less than open source version).");
        }
        if (currentVersion == 3 && toVersion >= 4) {
            migrateJobsv3tov4();
            currentVersion = 4;
        }
        if (currentVersion == 4 && toVersion >= 5) {
            migrateJobsv4tov5();
            currentVersion = 5;
        }
        if (currentVersion == 5 && toVersion >= 6) {
            migrateJobsv5tov6();
            currentVersion = 6;
        }
        if (currentVersion == 6 && toVersion >= 7) {
            migrateJobsv6tov7();
            currentVersion = 7;
        }
        if (currentVersion == 7 && toVersion >= 8) {
            migrateJobsv7tov8();
            currentVersion = 8;
        }
        if (currentVersion == 8 && toVersion >= 9) {
            migrateJobsv8tov9();
            currentVersion = 9;
        }
        if (currentVersion == 9 && toVersion >= 10) {
            migrateJobsv9tov10();
            currentVersion = 10;
        }
        // future updates of the jobs table are inserted here
        if (currentVersion == HarvesterDatabaseTables.JOBS.getRequiredVersion()
                && toVersion >= HarvesterDatabaseTables.JOBS.getRequiredVersion() + 1) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.JOBS.getTablename() + "' from version " + currentVersion + " to version "
                    + toVersion);
        }

        if (currentVersion > HarvesterDatabaseTables.JOBS.getRequiredVersion()) {
            throw new IllegalState("Database is in an illegalState: " + "The current version (" + currentVersion
                    + ") of table '" + HarvesterDatabaseTables.JOBS.getTablename()
                    + "' is not an acceptable/known version. ");
        }
    }

    /**
     * Migrate the configurations table.
     *
     * @param currentVersion the current version of the configurations table
     * @param toVersion the required version of the configurations table
     */
    private void upgradeConfigurationsTable(int currentVersion, int toVersion) {
        if (currentVersion < 3) {
            throw new IllegalState("Database is in an illegalState: " + "The current version " + currentVersion
                    + " of table '" + HarvesterDatabaseTables.CONFIGURATIONS.getTablename() + "' is not acceptable. "
                    + "(current version is less than open source version).");
        }
        if (currentVersion == 3 && toVersion >= 4) {
            migrateConfigurationsv3ov4();
            currentVersion = 4;
        }

        if (currentVersion == 4 && toVersion >= 5) {
            migrateConfigurationsv4tov5();
            currentVersion = 5;
        }
        // insert future migrations here
        if (currentVersion == HarvesterDatabaseTables.CONFIGURATIONS.getRequiredVersion()
                && toVersion >= HarvesterDatabaseTables.CONFIGURATIONS.getRequiredVersion() + 1) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.CONFIGURATIONS.getTablename() + "' from version " + currentVersion
                    + " to version " + toVersion);
        }

        if (currentVersion > HarvesterDatabaseTables.CONFIGURATIONS.getRequiredVersion()) {
            throw new IllegalState("Database is in an illegalState: " + "The current version (" + currentVersion
                    + ") of table '" + HarvesterDatabaseTables.CONFIGURATIONS.getTablename()
                    + "' is not an acceptable/known version. ");
        }
    }

    private void upgradeDomainsTable(int currentVersion, int toVersion) {
        if (currentVersion < 2) {
            throw new IllegalState("Database is in an illegalState: " + "The current version " + currentVersion
                    + " of table '" + HarvesterDatabaseTables.DOMAINS.getTablename() + "' is not acceptable. "
                    + "(current version is less than open source version).");
        }
        if (currentVersion == 2 && toVersion >= 3) {
            migrateDomainsv2tov3();
            currentVersion = 3;
        }
    }

    /**
     * Migrate the fullharvests table.
     *
     * @param currentVersion the current version of the fullharvests table
     * @param toVersion the required version of the fullharvests table
     */
    private void upgradeFullharvestsTable(int currentVersion, int toVersion) {
        if (currentVersion < 2) {
            throw new IllegalState("Database is in an illegalState: " + "The current version " + currentVersion
                    + " of table '" + HarvesterDatabaseTables.FULLHARVESTS.getTablename() + "' is not acceptable. "
                    + "(current version is less than open source version).");
        }
        if (currentVersion == 2 && toVersion >= 3) {
            migrateFullharvestsv2tov3();
            currentVersion = 3;
        }

        if (currentVersion == 3 && toVersion >= 4) {
            migrateFullharvestsv3tov4();
            currentVersion = 4;
        }

        if (currentVersion == 4 && toVersion >= 5) {
            migrateFullharvestsv4tov5();
            currentVersion = 5;
        }

        // insert future migrations here
        if (currentVersion == HarvesterDatabaseTables.FULLHARVESTS.getRequiredVersion()
                && toVersion >= HarvesterDatabaseTables.FULLHARVESTS.getRequiredVersion() + 1) {
            throw new NotImplementedException("No method exists for migrating table '"
                    + HarvesterDatabaseTables.FULLHARVESTS.getTablename() + "' from version " + currentVersion
                    + " to version " + toVersion);
        }
    }

    /**
     * Migrate the harvestchannel table.
     *
     * @param currentVersion the current version of the harvestchannel table
     * @param toVersion the required version of the harvestchannel table
     */
    private void upgradeHarvestchannelTable(int currentVersion, int toVersion) {
        if (currentVersion == 0 && toVersion >= 1) {
            createHarvestChannelTable();
            currentVersion = 1;
        }
    }

    protected abstract void createHarvestChannelTable();

    /**
     * Migrates the 'jobs' table from version 3 to version 4 consisting of a change of the field forcemaxbytes from int
     * to bigint and setting its default to -1. Furthermore the default value for field num_configs is set to 0.
     *
     * @throws IOFailure in case of problems in interacting with the database
     */
    protected abstract void migrateJobsv3tov4();

    /**
     * Migrates the 'jobs' table from version 4 to version 5 consisting of adding new fields 'resubmitted_as_job' and
     * 'submittedDate'.
     *
     * @throws IOFailure in case of problems in interacting with the database
     */
    protected abstract void migrateJobsv4tov5();

    /**
     * Migrates the 'configurations' table from version 3 to version 4. This consists of altering the default value of
     * field 'maxbytes' to -1.
     */
    protected abstract void migrateConfigurationsv3ov4();

    /**
     * Migrates the 'fullharvests' table from version 2 to version 3. This consists of altering the default value of
     * field 'maxbytes' to -1.
     */
    protected abstract void migrateFullharvestsv2tov3();

    /**
     * Migrates the 'runningjobshistory' table from version 1 to version 2. This consists of adding the new column
     * 'retiredQueuesCount'.
     */
    protected abstract void migrateRunningJobsHistoryTableV1ToV2();

    /**
     * Migrates the 'runningjobsmonitor' table from version 1 to version 2. This consists of adding the new column
     * 'retiredQueuesCount'.
     */
    protected abstract void migrateRunningJobsMonitorTableV1ToV2();

    /**
     * Migrates the 'domains' table from version 2 to version 3. This consists of altering the type of the crawlertraps
     * column to "text" in postgres, and noop in derbyDB
     */
    protected abstract void migrateDomainsv2tov3();

    /**
     * Creates the initial (version 1) of table 'global_crawler_trap_lists'.
     */
    protected abstract void createGlobalCrawlerTrapLists();

    /**
     * Creates the initial (version 1) of table 'global_crawler_trap_expressions'.
     */
    protected abstract void createGlobalCrawlerTrapExpressions();

    /**
     * Formats the LIMIT sub-clause of an SQL order clause. This sub-clause allows to paginate query results and its
     * syntax might be dependant on the target RDBMS
     *
     * @param limit the maximum number of rows to fetch.
     * @param offset the starting offset in the full query results.
     * @return the proper sub-clause.
     */
    public abstract String getOrderByLimitAndOffsetSubClause(long limit, long offset);

    /**
     * Returns true if the target RDBMS supports CLOBs. If possible seedlists will be stored as CLOBs.
     *
     * @return true if CLOBs are supported, false otherwise.
     */
    public abstract boolean supportsClob();

    /**
     * Create the frontierReportMonitor table in the database.
     */
    public abstract void createFrontierReportMonitorTable();

    /**
     * Create the frontierReportMonitor table in the database.
     */
    public abstract void createRunningJobsHistoryTable();

    /**
     * Create the frontierReportMonitor table in the database.
     */
    public abstract void createRunningJobsMonitorTable();

    /**
     * Migrates the 'jobs' table from version 5 to version 6. Adds the field 'forcemaxrunningtime'.
     *
     * @throws IOFailure in case of problems in interacting with the database
     */
    protected abstract void migrateJobsv5tov6();

    /**
     * Migrates the 'configurations' table from version 4 to version 5. This consists of altering the field 'maxobjects'
     * from being an int to a bigint.
     */
    protected abstract void migrateConfigurationsv4tov5();

    /**
     * Migrates the 'fullharvests' table from version 3 to version 4. This consists of adding the field
     * 'maxjobrunningtime'.
     */
    protected abstract void migrateFullharvestsv3tov4();

    /**
     * Migrates the 'fullharvests' table from version 4 to version 5. This consists of adding the field 'isindexready'.
     */
    protected abstract void migrateFullharvestsv4tov5();

    /**
     * Create the extendedfieldtype table in the database.
     */
    protected abstract void createExtendedFieldTypeTable();

    /**
     * Create the extendedfield table in the database.
     */
    protected abstract void createExtendedFieldTable();

    /**
     * Create the extendedfieldvalue table in the database.
     */
    protected abstract void createExtendedFieldValueTable();

    /**
     * Migrates the 'jobs' table from version 6 to version 7 consisting of adding the bigint fieldcontinuationof with
     * null as default.
     */
    protected abstract void migrateJobsv6tov7();

    /**
     * Migrates the 'jobs' table from version 7 to version 8 consisting of adding the date creationdate with null as
     * default.
     */
    protected abstract void migrateJobsv7tov8();

    /**
     * Migrates the 'jobs' table from version 8 to version 9 consisting of adding the string harvestname_prefix with
     * null as default.
     */
    protected abstract void migrateJobsv8tov9();

    /**
     * Migrates the 'harvestdefinitions' table from version 2 to version 3 consisting of adding the string audience with
     * null as default.
     */
    protected abstract void migrateHarvestdefinitionsv2tov3();

    /**
     * Migrates the 'harvestdefinitions' table from version 3 to version 4 consisting of adding the bigint channel_id
     * field.
     */
    protected abstract void migrateHarvestdefinitionsv3tov4();

    /**
     * Migrates the 'jobs' table from version 9 to version 10 consisting of adding the channel (varchar 300) and a
     * 'snapshot'
     */
    protected abstract void migrateJobsv9tov10();

    /**
     * Migrates the 'ExtendedFieldTable' from version 1 to version 2 consisting of adding the maxlen field
     */
    protected abstract void migrateExtendedFieldTableV1toV2();

    /**
     * Migrates the 'ExtendedFieldValueTable' from version 1 to version 2 changing the maxlen of content to 30000
     */
    protected abstract void migrateExtendedFieldTableValueV1toV2();

    /**
     * Update all tables in the enum class {@link HarvesterDatabaseTables} to the required version. There is no attempt
     * to undo the update.
     */
    public void updateTables() {
        for (HarvesterDatabaseTables table : HarvesterDatabaseTables.values()) {
            updateTable(table.getTablename(), table.getRequiredVersion());
        }
    }

}