question: public static void putDataPrefixToLayerList ( String dataPrefix , Properties props , String layerListProperty ) { Vector < String > layersValue = parseSpacedMarkers ( props . getProperty ( layerListProperty ) ) ; for ( Iterator < String > it = layersValue . iterator ( ) ; it . hasNext ( ) ; ) { String markerName = getScopedPropertyPrefix ( it . next ( ) ) ; props . setProperty ( markerName + Layer . DataPathPrefixProperty , dataPrefix ) ; } }
target:  If the layer has a dataPathPrefix attribute set, that attribute value can be used as a common path to prepend to any layer's data path. This allows you to set a relative path to files in the layer's properties, and then prepend the absolute path later at runtime. <p> The dataPathPrefix can be set in the properties for a layer, where it is pushed to the layer's attributes in Layer.setProperties(). This method is intended for layers that have sub-layers, so the parent layer can set that dataPathPrefix property on it's children automatically.