<code lang="groovy">
import java.awt.*
import java.awt.BorderLayout as BL

import javax.swing.WindowConstants as WC

import org.jdesktop.swingx.mapviewer.*
import org.jdesktop.swingx.JXMapViewer

import groovy.swing.SwingBuilder


def mapViewer = new JXMapViewer()
def tfi = new TileFactoryInfo(0, 20, 17, 256, true, true, "http://mt.google.com/mt?w=2.43", "x", "y", "zoom")

mapViewer.tileFactory = new DefaultTileFactory(tfi)
mapViewer.zoom = 9
mapViewer.centerPosition = [43.835, 2.329]
mapViewer.preferredSize = [800, 600]

frame = new SwingBuilder().frame(title: 'Groovy Maps', defaultCloseOperation: WC.DISPOSE_ON_CLOSE) {
    panel(layout: new BL()) {
        panel(constraints: BL.CENTER) { widget(mapViewer) }
        panel(constraints: BL.SOUTH) {
            button(text: "+", actionPerformed: { mapViewer.zoom -= 1 })
            button(text: "-", actionPerformed: { mapViewer.zoom += 1 })
        }
    }
}

frame.pack()
frame.visible = true
</code>