compareTo method
Compares two envelopes using lexicographic ordering. The ordering comparison is based on the usual numerical comparison between the sequence of ordinates. Null envelopes are less than all non-null envelopes.
@param o an Envelope object
Implementation
int compareTo(Object o) {
Envelope env = o as Envelope;
// compare nulls if present
if (isNull()) {
if (env.isNull()) return 0;
return -1;
} else {
if (env.isNull()) return 1;
}
// compare based on numerical ordering of ordinates
if (_minx < env._minx) return -1;
if (_minx > env._minx) return 1;
if (_miny < env._miny) return -1;
if (_miny > env._miny) return 1;
if (_maxx < env._maxx) return -1;
if (_maxx > env._maxx) return 1;
if (_maxy < env._maxy) return -1;
if (_maxy > env._maxy) return 1;
return 0;
}