RevertableConfiguration.java

/**
 * Copyright (c) 2008-2011 Sonatype, Inc.
 * All rights reserved. Includes the third-party code listed at http://www.sonatype.com/products/nexus/attributions.
 *
 * This program is free software: you can redistribute it and/or modify it only under the terms of the GNU Affero General
 * Public License Version 3 as published by the Free Software Foundation.
 *
 * 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 Affero General Public License Version 3
 * for more details.
 *
 * You should have received a copy of the GNU Affero General Public License Version 3 along with this program.  If not, see
 * http://www.gnu.org/licenses.
 *
 * Sonatype Nexus (TM) Open Source Version is available from Sonatype, Inc. Sonatype and Sonatype Nexus are trademarks of
 * Sonatype, Inc. Apache Maven is a trademark of the Apache Foundation. M2Eclipse is a trademark of the Eclipse Foundation.
 * All other trademarks are the property of their respective owners.
 */
package org.sonatype.nexus.configuration;

import org.sonatype.configuration.ConfigurationException;

/**
 * Revertable configuration is a configuration that is changeable, but may be be reverted (rollback the changes). The
 * changes are "visible" only after applyChanges() call.
 * 
 * @author cstamas
 */
public interface RevertableConfiguration
{
    /**
     * Returns true if this configuration holds some changes that are not persisted.
     * 
     * @return
     */
    boolean isDirty();

    /**
     * Validatyes the changes, if any.
     */
    void validateChanges()
        throws ConfigurationException;
    
    /**
     * Commits the changes. Resets the state of config "back to normal" (saved). Will call validateChanges() if needed.
     */
    void commitChanges()
        throws ConfigurationException;

    /**
     * Rollbacks the changes. Resets the state of config "back to normal" (saved).
     */
    void rollbackChanges();
}