public function testJson()
{
$expected = '{"type":"MultiPolygon","coordinates":[[[[0,0],[10,0],[10,10],[0,10],[0,0]]],[[[5,5],[7,5],[7,7],[5,7],[5,5]]]]}';
$polygons = array(array(array(array(0, 0), array(10, 0), array(10, 10), array(0, 10), array(0, 0))), array(array(array(5, 5), array(7, 5), array(7, 7), array(5, 7), array(5, 5))));
$multiPolygon = new MultiPolygon($polygons);
$this->assertEquals($expected, $multiPolygon->toJson());
}