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
*/
public void update(DataSource<?, ?, ?, ?> dataSource);
}