com.linuxbox.enkive.Main.java Source code

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Here is the source code for com.linuxbox.enkive.Main.java

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/*******************************************************************************
 * Copyright 2013 The Linux Box Corporation.
 *
 * This file is part of Enkive CE (Community Edition).
 *
 * Enkive CE is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 *
 * Enkive CE 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public
 * License along with Enkive CE. If not, see
 * <http://www.gnu.org/licenses/>.
 *******************************************************************************/
package com.linuxbox.enkive;

import java.io.IOException;
import java.util.Map;
import java.util.Map.Entry;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.AbstractApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.linuxbox.enkive.audit.AuditService;
import com.linuxbox.enkive.audit.AuditServiceException;
import com.linuxbox.enkive.audit.NullAuditService;
import com.linuxbox.enkive.tool.mongodb.MongoDbIndexManager;
import com.linuxbox.util.DirectoryManagement;
import com.linuxbox.util.dbmigration.DbMigrationService;

public abstract class Main {
    protected static final Log LOGGER;
    private static final String USER = AuditService.USER_SYSTEM;
    private static final String[] VERSION_CHECK_CONFIG_FILES = { "enkive-version-check.xml" };
    protected static final String[] NO_ARGS = {};

    protected AbstractApplicationContext context;
    protected AuditService auditService = null;

    final protected String[] arguments;
    final protected String[] configFiles;
    final protected boolean runVersionCheck;
    final protected boolean runIndexCheck;
    final protected boolean runAuditService;
    final protected String description;

    protected abstract void runCoreFunctionality(ApplicationContext context) throws Exception;

    protected abstract void preStartup();

    protected abstract void postStartup();

    protected abstract void preShutdown();

    protected abstract void postShutdown();

    static {
        try {
            DirectoryManagement.verifyDirectory(GeneralConstants.DEFAULT_LOG_DIRECTORY,
                    "default logging directory");
        } catch (IOException e) {
            throw new Error(e);
        }
        LOGGER = LogFactory.getLog("com.linuxbox.enkive");
    }

    public Main(String[] arguments, String[] configFiles, String description) {
        this(arguments, configFiles, description, true, true, true);
    }

    public Main(String[] arguments, String[] configFiles, String description, boolean runVersionCheck,
            boolean runIndexCheck, boolean runAuditService) {
        this.arguments = arguments;
        this.configFiles = configFiles;
        this.description = description;
        this.runVersionCheck = runVersionCheck;
        this.runIndexCheck = runIndexCheck;
        this.runAuditService = runAuditService;
    }

    protected void runVersionCheck() throws Exception {
        final AbstractApplicationContext versionCheckingContext = new ClassPathXmlApplicationContext(
                VERSION_CHECK_CONFIG_FILES);
        try {
            Map<String, DbMigrationService> migrationServices = versionCheckingContext
                    .getBeansOfType(DbMigrationService.class);
            if (migrationServices.isEmpty()) {
                final String message = "no version checking / migration services configured";
                LOGGER.fatal(message);
                throw new Exception(message);
            }
            for (Entry<String, DbMigrationService> service : migrationServices.entrySet()) {
                service.getValue().isUpToDate();
            }
        } finally {
            versionCheckingContext.close();
        }
    }

    public void start() throws Exception {
        preStartup();

        if (runVersionCheck) {
            runVersionCheck();
        }

        /*
         * IF WE GET HERE AND runVersionCheck IS TRUE, THE DATABASE IS
         * APPARENTLY UP TO DATE
         */

        context = new ClassPathXmlApplicationContext(configFiles);
        context.registerShutdownHook();

        if (runAuditService) {
            auditService = context.getBean("AuditLogService", AuditService.class);
        } else {
            // since no audit service is wanted, simply instantiate the null
            // version and let it throw away the log entries
            auditService = new NullAuditService();
        }

        auditService.addEvent(AuditService.SYSTEM_STARTUP, USER, description);

        if (runIndexCheck) {
            final MongoDbIndexManager mongoIndexManager = context.getBean(MongoDbIndexManager.class);
            mongoIndexManager.runCheckAndAutoEnsure();
        }

        postStartup();
    }

    public void stop() throws Exception {
        try {
            auditService.addEvent(AuditService.SYSTEM_SHUTDOWN, USER, description);
        } catch (AuditServiceException e) {
            LOGGER.error("received AuditServiceException: " + e.getMessage(), e);
        }

        preShutdown();

        context.close();

        postShutdown();
    }

    public void run() throws Exception {
        start();
        try {
            runCoreFunctionality(context);
        } finally {
            stop();
        }
    }
}