@Test
public void testDecode() {
// for all lat/lon pairs check decoded point is in the same bbox as the
// geohash formed by encoder
for (GeoHash gh : RandomGeohashes.fullRange()) {
BoundingBox bbox = gh.getBoundingBox();
GeoHash decodedHash = GeoHash.fromGeohashString(gh.toBase32());
WGS84Point decodedCenter = decodedHash.getBoundingBoxCenterPoint();
assertTrue(
"bbox " + bbox + " should contain the decoded center value " + decodedCenter,
bbox.contains(decodedCenter));
BoundingBox decodedBoundingBox = decodedHash.getBoundingBox();
assertEquals(bbox, decodedBoundingBox);
assertEquals(gh, decodedHash);
assertEquals(gh.toBase32(), decodedHash.toBase32());
}
}
@Test
public void testStepsBetween() {
GeoHash bl = GeoHash.withBitPrecision(37.7, -122.52, 35);
GeoHash ur = GeoHash.withBitPrecision(37.84, -122.35, 35);
long steps = GeoHash.stepsBetween(bl, bl);
assertEquals(steps, 0);
steps = GeoHash.stepsBetween(bl, bl.next(4));
assertEquals(steps, 4);
BoundingBoxGeoHashIterator iter =
new BoundingBoxGeoHashIterator(new TwoGeoHashBoundingBox(bl, ur));
int count = 0;
while (iter.hasNext()) {
iter.next();
count++;
}
assertEquals(12875, count);
int allHashes = 0;
int inBbox = 1;
int latMore = 0;
int lonMore = 0;
int bothMore = 0;
int latLess = 0;
int lonLess = 0;
int bothLess = 0;
int latLessLonMore = 0;
int latMoreLonLess = 0;
GeoHash idx = bl;
BoundingBox iterBbox = iter.getBoundingBox().getBoundingBox();
while (idx.compareTo(ur) < 0) {
idx = idx.next();
allHashes++;
if (iterBbox.contains(idx.getPoint())) {
inBbox++;
}
boolean latIsMore = false;
boolean latIsLess = false;
if (idx.getPoint().getLatitude() > iterBbox.getMaxLat()) {
latIsMore = true;
latMore++;
} else if (idx.getPoint().getLatitude() < iterBbox.getMinLat()) {
latIsLess = true;
latLess++;
}
if (idx.getPoint().getLongitude() > iterBbox.getMaxLon()) {
lonMore++;
if (latIsMore) {
bothMore++;
}
if (latIsLess) {
latLessLonMore++;
}
} else if (idx.getPoint().getLongitude() < iterBbox.getMinLon()) {
lonLess++;
if (latIsLess) {
bothLess++;
}
if (latIsMore) {
latMoreLonLess++;
}
}
}
// Just trying to understand where these GeoHashes are with regard to
// their bounding box.
steps = GeoHash.stepsBetween(bl, ur);
assertEquals(48472, steps);
assertEquals(steps, allHashes);
assertEquals(count, inBbox);
assertEquals(14938, latMore);
assertEquals(640, lonMore);
assertEquals(0, bothMore);
assertEquals(7680, latLess);
assertEquals(24391, lonLess);
assertEquals(0, bothLess);
assertEquals(240, latLessLonMore);
assertEquals(11811, latMoreLonLess);
assertEquals(
steps,
lonLess + latLess + latMore + lonMore + inBbox - latLessLonMore - latMoreLonLess - 1);
}