added shortest path finder with dijkstras alg

src/City.java

@@ -1,22 +1,37 @@
+import java.util.ArrayList;
+import java.util.List;
+
 public class City {
   private String name;
   private Station trainStation;
   private Station busStation;
-  private int row;
+  private Location location;
-  private int col;
 
-  City(String name, String train, String bus, int row, int col) {
+  City(String name, String bus, String train, int row, int col) {
     this.name = name;
     this.trainStation = new Station(TransportType.TRAIN, train);
     this.busStation = new Station(TransportType.BUS, bus);
+    this.location = new Location(row, col);
   }
 
-  City(String name, Station train, Station bus, int row, int col) {
+  City(String name, Station bus, Station train, int row, int col) {
     this.name = name;
     this.trainStation = train;
     this.busStation = bus;
-    this.row = row;
+    this.location = new Location(row, col);
-    this.col = col;
+  }
+
+  public List<Departure> getDestinations() {
+    List<Departure> departures = new ArrayList<>();
+
+    for (Departure dep : busStation.getDepartures()) {
+      departures.add(dep);
+    }
+    for (Departure dep : trainStation.getDepartures()) {
+      departures.add(dep);
+    }
+
+    return departures;
   }
 
   public String getName() {
@@ -43,20 +58,8 @@ public class City {
     this.busStation = busStation;
   }
 
-  public int getRow() {
+  public Location getLocation() {
-    return row;
+    return this.location;
-  }
-
-  public void setRow(int row) {
-    this.row = row;
-  }
-
-  public int getCol() {
-    return col;
-  }
-
-  public void setCol(int col) {
-    this.col = col;
   }
 
   @Override

src/CityManager.java

@@ -0,0 +1,14 @@
+import java.util.HashMap;
+import java.util.Map;
+
+public class CityManager {
+  private static Map<String, City> cities = new HashMap<>();
+
+  public static void addCity(City city) {
+    cities.put(city.getName(), city);
+  }
+
+  public static City getCityByName(String cityName) {
+    return cities.get(cityName);
+  }
+}

src/Departure.java

@@ -27,6 +27,11 @@ public class Departure {
     this.minTransferTime = minTransferTime;
   }
 
+  public City getDestinationCity() {
+
+    return CityManager.getCityByName(to);
+  }
+
   public TransportType getType() {
     return type;
   }
@@ -70,6 +75,6 @@ public class Departure {
         + price
         + ", minTransferTime="
         + minTransferTime
-        + '}';
+        + "}";
   }
 }

src/Graph.java

@@ -0,0 +1,89 @@
+import java.util.Comparator;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.PriorityQueue;
+
+public class Graph {
+  private City[][] matrix;
+
+  public static void main(String[] args) {
+    List<City> cities = JsonParser.parseCities("transport_data.json", "stations");
+    List<Departure> departures = JsonParser.getDeparturesList("transport_data.json", "departures");
+    cities = JsonParser.loadDepartures(cities, departures);
+    City[][] map = JsonParser.loadMap("transport_data.json", "countryMap", cities);
+
+    Graph graph = new Graph(map);
+    cities = JsonParser.loadDepartures(cities, departures);
+    System.out.println(cities.getFirst().getName() + " do " + cities.getLast().getName());
+    for (City city : cities) {
+      CityManager.addCity(city);
+    }
+    Map<Location, Double> result =
+        graph.calculateShortestPath(cities.getFirst(), cities.get(3), "price");
+    System.out.println(
+        cities.getLast().getName() + " = " + result.get(cities.get(3).getLocation()));
+  }
+
+  public Map<Location, Double> calculateShortestPath(City startCity, City endCity, String type) {
+    int n = matrix.length;
+    int m = matrix[0].length;
+
+    Map<Location, Double> distances = new HashMap<>();
+    for (int i = 0; i < n; i++) {
+      for (int j = 0; j < m; j++) {
+        distances.put(new Location(i, j), Double.MAX_VALUE);
+      }
+    }
+
+    distances.put(startCity.getLocation(), 0.0);
+
+    PriorityQueue<City> pq =
+        new PriorityQueue<>(Comparator.comparingDouble(city -> distances.get(city.getLocation())));
+    pq.add(startCity);
+
+    while (!pq.isEmpty()) {
+      City current = pq.poll();
+
+      // If we reached the end city, we can stop early
+      if (current == endCity) {
+        break;
+      }
+
+      for (Departure dep : current.getDestinations()) {
+        City neighborCity = dep.getDestinationCity();
+        Location neighborLocation = neighborCity.getLocation();
+
+        double newCost = 0.0;
+        if (type.equals("price")) {
+          newCost = distances.get(current.getLocation()) + dep.getPrice();
+        } else if (type.equals("time")) {
+          newCost = distances.get(current.getLocation()) + dep.getDuration();
+        }
+
+        if (newCost < distances.get(neighborLocation)) {
+          distances.put(neighborLocation, newCost);
+          pq.add(neighborCity);
+        }
+      }
+    }
+
+    return distances;
+  }
+
+  public Graph(City[][] matrix) {
+    this.matrix = matrix;
+  }
+
+  public void updateMatrix(City[][] matrix) {
+    this.matrix = matrix;
+  }
+
+  public City[][] getMatrix() {
+    return matrix;
+  }
+
+  public City getCity(Location loc) {
+    return matrix[loc.getX()][loc.getY()];
+  }
+}

src/JsonParser.java

@@ -2,20 +2,26 @@ import java.io.BufferedReader;
 import java.io.FileReader;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 
 public class JsonParser {
-
+  /*
     public static void main(String[] args) {
-    // String[][] map = JsonParser.parseCountryMap("transport_data.json", "countryMap");
+      String[][] map = JsonParser.parseCountryMap("transport_data.json", "countryMap");
-    // JsonParser.parseCities("transport_data.json", "stations");
+      List<City> cities = JsonParser.parseCities("transport_data.json", "stations");
-    JsonParser.getDeparturesList("transport_data.json", "departures");
+      List<Departure> departures = JsonParser.getDeparturesList("transport_data.json", "departures");
-  }
 
+      cities = JsonParser.loadDepartures(cities, departures);
+      for (City city : cities) {
+        System.out.println(city);
+      }
+    }
+  */
   public static String getValue(String fileName, String key) {
     StringBuilder json = new StringBuilder();
-    try {
+    try (BufferedReader reader = new BufferedReader(new FileReader(fileName))) {
-      BufferedReader reader = new BufferedReader(new FileReader(fileName));
       String line;
       while ((line = reader.readLine()) != null) {
         json.append(line.trim());
@@ -39,6 +45,17 @@ public class JsonParser {
     return jsonString.substring(startIndex, endIndex);
   }
 
+  public static City[][] loadMap(String fileName, String key, List<City> cities) {
+    String[][] cityMap = parseCountryMap(fileName, key);
+    City[][] map = new City[cityMap.length][cityMap[0].length];
+
+    for (City city : cities) {
+      map[city.getLocation().getX()][city.getLocation().getY()] = city;
+    }
+
+    return map;
+  }
+
   public static String[][] parseCountryMap(String fileName, String key) {
 
     String mapData = getValue(fileName, key);
@@ -55,9 +72,6 @@ public class JsonParser {
               .map(s -> s.replaceAll("\"", "").trim())
               .filter(s -> !s.isEmpty())
               .toArray(String[]::new);
-      for (String city : cities) {
-        System.out.println(city);
-      }
       if (cities.length > 0) matrixList.add(cities);
     }
     String[][] result = new String[matrixList.size()][];
@@ -65,13 +79,13 @@ public class JsonParser {
 
       result[i] = matrixList.get(i);
     }
-
+    /*
         for (int i = 0; i < result.length; i++) {
           for (int j = 0; j < result[i].length; j++) {
             System.out.println("result[" + i + "][" + j + "] = " + result[i][j]);
           }
         }
-
+    */
     return result;
   }
 
@@ -79,7 +93,6 @@ public class JsonParser {
     List<Departure> departures = new ArrayList<>();
 
     String departuresJson = getValue(fileName, key);
-    System.out.println(departuresJson);
 
     String res =
         departuresJson
@@ -91,8 +104,6 @@ public class JsonParser {
                 "type:\\s|\\sfrom:\\s|\\sto:\\s|\\sdepartureTime:\\s|\\sduration:\\s|\\sprice:\\s|\\sminTransferTime:\\s",
                 "");
 
-    System.out.println(res);
-
     String[] arr = res.split("\\|");
     for (String a : arr) {
       String[] temp = a.split(",");
@@ -105,16 +116,13 @@ public class JsonParser {
               Integer.parseInt(temp[4]),
               Double.parseDouble(temp[5]),
               Integer.parseInt(temp[6])));
-      System.out.println(a);
     }
 
-    for (Departure dep : departures) System.out.println(dep);
     return departures;
   }
 
   public static List<City> parseCities(String fileName, String key) {
     String cityData = getValue(fileName, key);
-    System.out.println(cityData);
     String res =
         cityData
             .replaceAll("[\\[\\]]+", "")
@@ -130,38 +138,82 @@ public class JsonParser {
       String[] temp = arr[i].split(",");
       list.add(temp);
     }
-    int i = 0;
     List<String> temp = new ArrayList<>();
     List<String> formatedList = new ArrayList<>();
     for (String[] a : list) {
       temp.clear();
       formatedList.clear();
-      System.out.println(i);
-      i++;
       for (String b : a) {
         temp.add(b);
       }
       for (String item : temp) {
         item = (item.replaceAll("\\\"[a-zA-Z]+\\\":\\s", "").trim().replaceAll("\\\"", ""));
-        System.out.println(item);
       }
 
       for (int j = 0; j < temp.size(); j++) {
         formatedList.add(
             temp.get(j).replaceAll("\\\"[a-zA-Z]+\\\":\\s", "").trim().replaceAll("\\\"", ""));
-        System.out.println(formatedList.get(j));
       }
 
-      cities.add(
+      String[] parts = formatedList.get(0).split("_");
-          new City(
+      String name = formatedList.get(0);
-              formatedList.get(0),
+      String bus = formatedList.get(1);
-              formatedList.get(1),
+      String train = formatedList.get(2);
-              formatedList.get(2),
+      int x = Integer.parseInt(parts[1]);
-              Integer.parseInt(String.valueOf(formatedList.get(0).charAt(2))),
+      int y = Integer.parseInt(parts[2]);
-              Integer.parseInt(String.valueOf(formatedList.get(0).charAt(4)))));
+      cities.add(new City(name, bus, train, x, y));
     }
+    return cities;
+  }
+
+  // Way to slow for big sets of data because it has O(n*m)
+  public static List<City> loadDeparturesOld(List<City> cities, List<Departure> departures) {
+
+    for (Departure dep : departures) {
+
       for (City city : cities) {
-      System.out.println(city);
+
+        if (dep.getType() == TransportType.BUS) {
+          if (dep.getFrom().equals(city.getBusStation().getName())) {
+            city.getBusStation().addDeparture(dep);
+          }
+        } else if (dep.getType() == TransportType.TRAIN) {
+
+          if (dep.getFrom().equals(city.getTrainStation().getName())) {
+            city.getTrainStation().addDeparture(dep);
+          }
+        }
+      }
+    }
+    return cities;
+  }
+
+  public static List<City> loadDepartures(List<City> cities, List<Departure> departures) {
+
+    Map<String, City> stationToCityMap = new HashMap();
+
+    for (City city : cities) {
+      if (city.getBusStation() != null) {
+        stationToCityMap.put(city.getBusStation().getName(), city);
+      }
+      if (city.getBusStation() != null) {
+        stationToCityMap.put(city.getTrainStation().getName(), city);
+      }
+    }
+
+    for (Departure dep : departures) {
+      City city = stationToCityMap.get(dep.getFrom());
+
+      if (city != null) {
+        if (dep.getType() == TransportType.BUS
+            && city.getBusStation().getName().equals(dep.getFrom())) {
+
+          city.getBusStation().addDeparture(dep);
+        } else if (dep.getType() == TransportType.TRAIN
+            && city.getTrainStation().getName().equals(dep.getFrom())) {
+          city.getTrainStation().addDeparture(dep);
+        }
+      }
     }
     return cities;
   }
@@ -169,7 +221,6 @@ public class JsonParser {
   private static int findPair(String str, int startIndex) {
 
     char open = str.charAt(startIndex);
-    System.out.println(open);
     char closed = (open == '[') ? ']' : '}';
 
     int depth = 0;

src/Location.java

@@ -0,0 +1,41 @@
+import java.util.Objects;
+
+public class Location {
+
+  private int x;
+  private int y;
+
+  public Location(int x, int y) {
+    this.x = x;
+    this.y = y;
+  }
+
+  public int getX() {
+    return x;
+  }
+
+  public void setX(int x) {
+    this.x = x;
+  }
+
+  public int getY() {
+    return y;
+  }
+
+  public void setY(int y) {
+    this.y = y;
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) return true;
+    if (o == null || getClass() != o.getClass()) return false;
+    Location location = (Location) o;
+    return x == location.x && y == location.y;
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(x, y);
+  }
+}

src/Station.java

@@ -13,4 +13,24 @@ public class Station {
     this.type = type;
     this.name = name;
   }
+
+  public TransportType getType() {
+    return type;
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  public List<Departure> getDepartures() {
+    return departures;
+  }
+
+  public void addDeparture(Departure departure) {
+    departures.add(departure);
+  }
+  @Override
+  public String toString() {
+    return "Station{" + "type=" + type + ", name=" + name + ", departures=" + departures;
+  }
 }

src/TransportDataGenerator.java

@@ -7,11 +7,11 @@ public class TransportDataGenerator {
   private int n;
   private int m;
 
-  private static final int DEPARTURES_PER_STATION = 3;
+  private static final int DEPARTURES_PER_STATION = 1;
   private static final Random random = new Random();
 
   public static void main(String[] args) {
-    TransportDataGenerator generator = new TransportDataGenerator(3, 4);
+    TransportDataGenerator generator = new TransportDataGenerator(2, 2);
     TransportData data = generator.generateData();
     generator.saveToJson(data, "transport_data.json");
     System.out.println("Podaci su generisani i sacuvani kao transport_data.json");

src/User.java

@@ -0,0 +1,48 @@
+public class User {
+  private String name;
+  private int id;
+  private Location location;
+  private Location destination;
+
+  private static int idCounter = 1;
+  // :TODO:
+  private static final String ID_FILE = "id_counter.txt";
+
+  public User(String name) {
+    this.name = name;
+    this.id = idCounter++;
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  public void setName(String name) {
+    this.name = name;
+  }
+
+  public int getId() {
+    return id;
+  }
+
+  public Location getLocation() {
+    return location;
+  }
+
+  public void setLocation(Location location) {
+    this.location = location;
+  }
+
+  public Location getDestination() {
+    return destination;
+  }
+
+  public void setDestination(Location destination) {
+    this.destination = destination;
+  }
+
+  @Override
+  public String toString() {
+    return "User{id=" + id + ", name='" + name + "'}";
+  }
+}