refactor: extract interfaces for TransferService and TransferRepository

Author: jessicaKoehnke

application/src/main/java/org/opentripplanner/routing/algorithm/raptoradapter/transit/mappers/RaptorTransitDataMapper.java

@@ -48,23 +48,25 @@ public class RaptorTransitDataMapper {
 
   private final TransitService transitService;
   private final SiteRepository siteRepository;
-  private final TransferRepository transferService;
+  private final TransferRepository transferRepository;
 
   private RaptorTransitDataMapper(
     TimetableRepository timetableRepository,
-    TransferRepository transferService
+    TransferRepository transferRepository
   ) {
     this.transitService = new DefaultTransitService(timetableRepository);
     this.siteRepository = timetableRepository.getSiteRepository();
-    this.transferService = transferService;
+    this.transferRepository = transferRepository;
   }
 
   public static RaptorTransitData map(
     TransitTuningParameters tuningParameters,
     TimetableRepository timetableRepository,
-    TransferRepository transferService
+    TransferRepository transferRepository
   ) {
-    return new RaptorTransitDataMapper(timetableRepository, transferService).map(tuningParameters);
+    return new RaptorTransitDataMapper(timetableRepository, transferRepository).map(
+      tuningParameters
+    );
   }
 
   private RaptorTransitData map(TransitTuningParameters tuningParameters) {
@@ -78,7 +80,7 @@ private RaptorTransitData map(TransitTuningParameters tuningParameters) {
 
     tripPatternsByStopByDate = mapTripPatterns(allTripPatterns);
 
-    transfersByStopIndex = mapTransfers(siteRepository, transferService);
+    transfersByStopIndex = mapTransfers(siteRepository, transferRepository);
 
     TransferIndexGenerator transferIndexGenerator = null;
     if (OTPFeature.TransferConstraints.isOn()) {

application/src/main/java/org/opentripplanner/routing/algorithm/raptoradapter/transit/mappers/TransfersMapper.java

@@ -16,7 +16,7 @@ class TransfersMapper {
    */
   static List<List<Transfer>> mapTransfers(
     SiteRepository siteRepository,
-    TransferRepository transferService
+    TransferRepository transferRepository
   ) {
     List<List<Transfer>> transfersByStopIndex = new ArrayList<>();
 
@@ -29,7 +29,7 @@ static List<List<Transfer>> mapTransfers(
 
       ArrayList<Transfer> list = new ArrayList<>();
 
-      for (PathTransfer pathTransfer : transferService.getTransfersByStop(stop)) {
+      for (PathTransfer pathTransfer : transferRepository.getTransfersByStop(stop)) {
         if (pathTransfer.to instanceof RegularStop) {
           int toStopIndex = pathTransfer.to.getIndex();
           Transfer newTransfer;

application/src/main/java/org/opentripplanner/standalone/configure/ConstructApplication.java

@@ -233,7 +233,7 @@ private void initEllipsoidToGeoidDifference() {
    */
   public static void createRaptorTransitData(
     TimetableRepository timetableRepository,
-    TransferRepository transferService,
+    TransferRepository transferRepository,
     TransitTuningParameters tuningParameters
   ) {
     if (!timetableRepository.hasTransit() || !timetableRepository.isIndexed()) {
@@ -243,7 +243,7 @@ public static void createRaptorTransitData(
     }
     LOG.info("Creating transit layer for Raptor routing.");
     timetableRepository.setRaptorTransitData(
-      RaptorTransitDataMapper.map(tuningParameters, timetableRepository, transferService)
+      RaptorTransitDataMapper.map(tuningParameters, timetableRepository, transferRepository)
     );
     timetableRepository.setRealtimeRaptorTransitData(
       new RaptorTransitData(timetableRepository.getRaptorTransitData())

application/src/main/java/org/opentripplanner/standalone/configure/ConstructApplicationFactory.java

@@ -56,7 +56,7 @@
 import org.opentripplanner.street.StreetRepository;
 import org.opentripplanner.street.service.StreetLimitationParametersServiceModule;
 import org.opentripplanner.transfer.TransferRepository;
-import org.opentripplanner.transfer.TransferServiceModule;
+import org.opentripplanner.transfer.configure.TransferServiceModule;
 import org.opentripplanner.transit.configure.TransitModule;
 import org.opentripplanner.transit.service.TimetableRepository;
 import org.opentripplanner.transit.service.TransitService;

application/src/main/java/org/opentripplanner/standalone/configure/LoadApplicationFactory.java

@@ -29,7 +29,7 @@
 import org.opentripplanner.street.StreetRepository;
 import org.opentripplanner.street.configure.StreetRepositoryModule;
 import org.opentripplanner.transfer.TransferRepository;
-import org.opentripplanner.transfer.TransferRepositoryModule;
+import org.opentripplanner.transfer.configure.TransferRepositoryModule;
 import org.opentripplanner.transit.service.TimetableRepository;
 
 /**

application/src/main/java/org/opentripplanner/transfer/TransferRepository.java

@@ -1,71 +1,32 @@
 package org.opentripplanner.transfer;
 
-import com.google.common.collect.HashMultimap;
 import com.google.common.collect.Multimap;
 import java.io.Serializable;
 import java.util.Collection;
-import java.util.Collections;
 import java.util.List;
 import org.opentripplanner.model.PathTransfer;
 import org.opentripplanner.routing.api.request.StreetMode;
 import org.opentripplanner.transit.model.site.StopLocation;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
-public class TransferRepository implements Serializable {
+/**
+ * This repository holds all transfers that are calculated between different stops for different
+ * modes. It is populated during the graph build process and saved into the serialized graph object.
+ * It should only be accessed directly during graph building, not during OTP server runtime. Use the
+ * {@link TransferService} instead, once transfer updates are implemented it will handle mutability
+ * correctly.
+ */
+public interface TransferRepository extends Serializable {
+  Collection<PathTransfer> getTransfersByStop(StopLocation stop);
 
-  // ToDo: I would prefer if this was package private, but right now the graph builder needs to
-  // write in here
+  List<PathTransfer> findTransfers(StreetMode mode);
 
-  private static final Logger LOG = LoggerFactory.getLogger(TransferRepository.class);
+  Collection<PathTransfer> getAllPathTransfers();
 
-  private final Multimap<StopLocation, PathTransfer> transfersByStop = HashMultimap.create();
+  void addAllTransfersByStops(Multimap<StopLocation, PathTransfer> transfersByStop);
 
-  private transient TransferIndex index;
+  void index();
 
-  public TransferRepository() {
-    LOG.info("Initializing TransferRepository");
-  }
+  Collection<PathTransfer> getTransfersToStop(StopLocation stopLocation);
 
-  public Collection<PathTransfer> getTransfersByStop(StopLocation stop) {
-    return transfersByStop.get(stop);
-  }
-
-  /** Pre-generated transfers between all stops filtered based on the modes in the PathTransfer. */
-  public List<PathTransfer> findTransfers(StreetMode mode) {
-    return transfersByStop
-      .values()
-      .stream()
-      .filter(pathTransfer -> pathTransfer.getModes().contains(mode))
-      .toList();
-  }
-
-  public Collection<PathTransfer> getAllPathTransfers() {
-    return transfersByStop.values();
-  }
-
-  public void addAllTransfersByStops(Multimap<StopLocation, PathTransfer> transfersByStop) {
-    // invalidateIndex();
-    this.transfersByStop.putAll(transfersByStop);
-  }
-
-  public void index() {
-    if (index == null) {
-      index = new TransferIndex(this);
-    }
-  }
-
-  public Collection<PathTransfer> getTransfersToStop(StopLocation stopLocation) {
-    if (index == null) {
-      return Collections.emptyList();
-    }
-    return index.getTransfersToStop(stopLocation);
-  }
-
-  public Collection<PathTransfer> getTransfersFromStop(StopLocation stopLocation) {
-    if (index == null) {
-      return Collections.emptyList();
-    }
-    return index.getTransfersFromStop(stopLocation);
-  }
+  Collection<PathTransfer> getTransfersFromStop(StopLocation stopLocation);
 }

application/src/main/java/org/opentripplanner/transfer/TransferRepositoryModule.java

@@ -1,46 +1,19 @@
 package org.opentripplanner.transfer;
 
 import java.util.Collection;
-import java.util.List;
 import org.opentripplanner.model.PathTransfer;
-import org.opentripplanner.routing.api.request.StreetMode;
 import org.opentripplanner.transit.model.site.StopLocation;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 /**
- * This class provides read access to transfers. Maybe this will be a TransferSnapshot or similar
- * once we implement the concurrency management for updates
+ * Access transfers during OTP server runtime. It provides a frozen view of all these elements at a
+ * point in time, which is not affected by ongoing transfer updates, allowing results to remain
+ * stable over the course of a request.
  */
-public class TransferService {
+public interface TransferService {
 
-  private static final Logger LOG = LoggerFactory.getLogger(TransferService.class);
+  Collection<PathTransfer> getTransfersByStop(StopLocation stop);
 
-  private final TransferRepository transferRepository;
+  Collection<PathTransfer> getTransfersFromStop(StopLocation stopLocation);
 
-  public TransferService(TransferRepository transferRepository) {
-    this.transferRepository = transferRepository;
-    LOG.info("Initializing TransferService");
-  }
-
-  public Collection<PathTransfer> getTransfersByStop(StopLocation stop) {
-    return transferRepository.getTransfersByStop(stop);
-  }
-
-  /** Pre-generated transfers between all stops filtered based on the modes in the PathTransfer. */
-  public List<PathTransfer> findTransfers(StreetMode mode) {
-    return transferRepository.findTransfers(mode);
-  }
-
-  public Collection<PathTransfer> getAllPathTransfers() {
-    return transferRepository.getAllPathTransfers();
-  }
-
-  public Collection<PathTransfer> getTransfersToStop(StopLocation stopLocation) {
-    return transferRepository.getTransfersToStop(stopLocation);
-  }
-
-  public Collection<PathTransfer> getTransfersFromStop(StopLocation stopLocation) {
-    return transferRepository.getTransfersFromStop(stopLocation);
-  }
+  Collection<PathTransfer> getTransfersToStop(StopLocation stopLocation);
 }

application/src/main/java/org/opentripplanner/transfer/TransferService.java

@@ -0,0 +1,17 @@
+package org.opentripplanner.transfer.configure;
+
+import dagger.Module;
+import dagger.Provides;
+import jakarta.inject.Singleton;
+import org.opentripplanner.transfer.TransferRepository;
+import org.opentripplanner.transfer.internal.DefaultTransferRepository;
+
+@Module
+public class TransferRepositoryModule {
+
+  @Provides
+  @Singleton
+  public TransferRepository provideTransferRepository() {
+    return new DefaultTransferRepository();
+  }
+}