org.opentripplanner.ext.sorlandsbanen.PathKey Maven / Gradle / Ivy
package org.opentripplanner.ext.sorlandsbanen;
import org.opentripplanner.raptor.api.path.PathLeg;
import org.opentripplanner.raptor.api.path.RaptorPath;
/**
* The purpose of this class is to create a key to be able to compare paths so duplicate results
* can be ignored.
*
* Creating a good key for a path is not easy. For example, should a small variation in the street
* routing for an access/egress leg count as a significant difference? The solution here is
* straightforward. It creates a hash of the access-, egress- and transit-legs in the path,
* ignoring transfer legs. This approach may drop valid results if there are hash collisions,
* but since this is a Sandbox module and the investment in this code is minimal, we will accept
* the risk.
*/
final class PathKey {
private final int hash;
PathKey(RaptorPath path) {
this.hash = hash(path);
}
private static int hash(RaptorPath path) {
int result = 1;
PathLeg leg = path.accessLeg();
while (!leg.isEgressLeg()) {
result = 31 * result + leg.toStop();
result = 31 * result + leg.toTime();
if (leg.isTransitLeg()) {
result = 31 * result + leg.asTransitLeg().trip().pattern().debugInfo().hashCode();
}
leg = leg.nextLeg();
}
result = 31 * result + leg.toTime();
return result;
}
@Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o.getClass() != PathKey.class) {
return false;
}
return hash == ((PathKey) o).hash;
}
@Override
public int hashCode() {
return hash;
}
}