@Test
public void testNext() {
double lat = 37.7;
double lon = -122.52;
GeoHash hash = GeoHash.withBitPrecision(lat, lon, 10);
GeoHash next = hash.next();
assertTrue(hash.compareTo(next) < 0);
}
@Test
public void testNextPrev() {
double lat = 37.7;
double lon = -122.52;
GeoHash hash = GeoHash.withBitPrecision(lat, lon, 35);
GeoHash next = hash.next(2);
assertTrue(hash.compareTo(next) < 0);
GeoHash prev1 = next.prev();
GeoHash prev2 = prev1.next(-1);
assertTrue(prev1.compareTo(next) < 0);
System.out.println("hash: " + hash.toBase32());
System.out.println("next: " + next.toBase32());
System.out.println("prev1: " + prev1.toBase32());
System.out.println("prev2: " + prev2.toBase32());
assertTrue(prev2.compareTo(prev1) < 0);
assertTrue(prev2.compareTo(hash) == 0);
}
@Test
public void testToLongAndBack() {
double lat = 40.390943;
double lon = -75.9375;
GeoHash hash = GeoHash.withCharacterPrecision(lat, lon, 10);
long lv = hash.longValue();
assertEquals(lv + (1 << (64 - hash.significantBits())), hash.next().longValue());
GeoHash hashFromLong = GeoHash.fromLongValue(lv, hash.significantBits());
assertEquals("dr4jb0bn21", hashFromLong.toBase32());
assertEquals(hash, hashFromLong);
}
@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);
}
