// License: GPL. For details, see LICENSE file.
package org.openstreetmap.josm.plugins.graphview.core.data;

/**
 * observer that will be informed about changes in a DataSource
 * if it has been registered using {@link DataSource#addObserver(DataSourceObserver)}.
 * Not every DataSource will send updates, because some don't change.
 */
public interface DataSourceObserver {

    /**
     * informs this observer about changes in an observed data source
     * @param dataSource  observed data source that has changed; != null
     */
    void update(DataSource<?, ?, ?, ?> dataSource);
}
