#27: WIP

Signed-off-by: Dominik Säume <Dominik.Saeume@hmmh.de>

.idea/dataSources.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="DataSourceManagerImpl" format="xml" multifile-model="true">
-    <data-source source="LOCAL" name="nursingHome.db" uuid="5a5b8be1-080b-4129-b89d-42f1ea832b90">
+    <data-source source="LOCAL" name="Database" uuid="5a5b8be1-080b-4129-b89d-42f1ea832b90">
       <driver-ref>sqlite.xerial</driver-ref>
       <synchronize>true</synchronize>
       <jdbc-driver>org.sqlite.JDBC</jdbc-driver>

src/main/java/de/hitec/nhplus/fixtures/MedicationFixture.java

@@ -1,17 +1,17 @@
 package de.hitec.nhplus.fixtures;
 
-import de.hitec.nhplus.Main;
-import de.hitec.nhplus.datastorage.DaoFactory;
-import de.hitec.nhplus.medication.Ingredient;
-import de.hitec.nhplus.medication.Medication;
-import de.hitec.nhplus.medication.database.MedicationDao;
-
 import java.io.InputStream;
 import java.nio.charset.StandardCharsets;
 import java.sql.Connection;
 import java.sql.SQLException;
 import java.util.*;
 
+import de.hitec.nhplus.Main;
+import de.hitec.nhplus.datastorage.DaoFactory;
+import de.hitec.nhplus.medication.Ingredient;
+import de.hitec.nhplus.medication.Medication;
+import de.hitec.nhplus.medication.database.MedicationDao;
+
 /**
  * {@link Fixture} for {@link Medication}.
  *
@@ -20,11 +20,13 @@ import java.util.*;
 public class MedicationFixture implements Fixture<Medication> {
     private static final String SCHEMA = "/de/hitec/nhplus/medication/database/Medication.sql";
     private static final String INGREDIENT_SCHEMA = "/de/hitec/nhplus/medication/database/Medication_Ingredient.sql";
+    private static final String ALTERNATIVE_SCHEMA = "/de/hitec/nhplus/medication/database/Medication_Alternative.sql";
 
     @Override
     public void dropTable(Connection connection) throws SQLException {
         connection.createStatement().execute("DROP TABLE IF EXISTS medication");
-        connection.createStatement().execute("DROP TABLE IF EXISTS  medication_ingredient");
+        connection.createStatement().execute("DROP TABLE IF EXISTS medication_ingredient");
+        connection.createStatement().execute("DROP TABLE IF EXISTS medication_alternative");
     }
 
     @Override
@@ -32,16 +34,25 @@ public class MedicationFixture implements Fixture<Medication> {
 
         final InputStream schema = Main.class.getResourceAsStream(SCHEMA);
         final InputStream ingredientSchema = Main.class.getResourceAsStream(INGREDIENT_SCHEMA);
+        final InputStream alternativeSchema = Main.class.getResourceAsStream(ALTERNATIVE_SCHEMA);
+
         assert schema != null;
         assert ingredientSchema != null;
+        assert alternativeSchema != null;
+
         String SQL = new Scanner(schema, StandardCharsets.UTF_8)
-                .useDelimiter("\\A")
+            .useDelimiter("\\A")
-                .next();
+            .next();
         String ingredientSQL = ";" + new Scanner(ingredientSchema, StandardCharsets.UTF_8)
-                .useDelimiter("\\A")
+            .useDelimiter("\\A")
-                .next();
+            .next();
+        String alternativeSQL = ";" + new Scanner(alternativeSchema, StandardCharsets.UTF_8)
+            .useDelimiter("\\A")
+            .next();
+
         connection.createStatement().execute(SQL);
         connection.createStatement().execute(ingredientSQL);
+        connection.createStatement().execute(alternativeSQL);
 
     }
 
@@ -67,86 +78,106 @@ public class MedicationFixture implements Fixture<Medication> {
         Ingredient warfarinnatrium = new Ingredient("Warfarinnatrium");
 
         medications.add(new Medication(
-                "Metformin",
+            "Metformin",
-                "AstraZeneca",
+            "AstraZeneca",
-                List.of(
+            List.of(
-                        metforminhydrochlorid,
+                metforminhydrochlorid,
-                        cellulose,
+                cellulose,
-                        povidon,
+                povidon,
-                        magnesiumstearat
+                magnesiumstearat
-                ),
+            ),
-                "Übelkeit, Durchfall, Laktatazidose (selten)",
+            "Übelkeit, Durchfall, Laktatazidose (selten)",
-                "Oral",
+            "Oral",
-                100
+            100,
+            new ArrayList<>()
         ));
         medications.add(new Medication(
-                "Lisinopril",
+            "Lisinopril",
-                "Teva Pharmaceuticals",
+            "Teva Pharmaceuticals",
-                List.of(
+            List.of(
-                        lisinoprilDihydrat,
+                lisinoprilDihydrat,
-                        mannitol,
+                mannitol,
-                        calciumphosphat,
+                calciumphosphat,
-                        magnesiumstearat
+                magnesiumstearat
-                ),
+            ),
-                "Schwindel, trockener Husten",
+            "Schwindel, trockener Husten",
-                "Oral",
+            "Oral",
-                150
+            150,
+            new ArrayList<>()
         ));
         medications.add(new Medication(
-                "Simvastatin",
+            "Simvastatin",
-                "Mylan",
+            "Mylan",
-                List.of(
+            List.of(
-                        simvastatin,
+                simvastatin,
-                        laktose,
+                laktose,
-                        cellulose,
+                cellulose,
-                        magnesiumstearat
+                magnesiumstearat
-                ),
+            ),
-                "Muskelschmerzen, Leberprobleme(selten)",
+            "Muskelschmerzen, Leberprobleme(selten)",
-                "Oral",
+            "Oral",
-                80
+            80,
+            new ArrayList<>()
         ));
         medications.add(new Medication(
-                "Enoxaparin",
+            "Enoxaparin",
-                "Sanofi",
+            "Sanofi",
-                List.of(
+            List.of(
-                        enoxaparinNatrium,
+                enoxaparinNatrium,
-                        benzylalkohol,
+                benzylalkohol,
-                        wasser
+                wasser
-                ),
+            ),
-                "Blutungen, Reaktionen an der Injektionsstelle",
+            "Blutungen, Reaktionen an der Injektionsstelle",
-                "Unterhautinjektion",
+            "Unterhautinjektion",
-                120
+            120,
+            new ArrayList<>()
         ));
         medications.add(new Medication(
-                "Levothyroxin",
+            "Levothyroxin",
-                "Sandoz",
+            "Sandoz",
-                List.of(
+            List.of(
-                        levothyroxinnatrium,
+                levothyroxinnatrium,
-                        laktose,
+                laktose,
-                        staerke,
+                staerke,
-                        akaziengummi
+                akaziengummi
-                ),
+            ),
-                "Herzrasen, Gewichtsverlust",
+            "Herzrasen, Gewichtsverlust",
-                "Oral",
+            "Oral",
-                90
+            90,
+            new ArrayList<>()
         ));
         medications.add(new Medication(
-                "Warfarin",
+            "Warfarin",
-                "Apotex Inc.",
+            "Apotex Inc.",
-                List.of(
+            List.of(
-                        warfarinnatrium,
+                warfarinnatrium,
-                        laktose,
+                laktose,
-                        staerke,
+                staerke,
-                        magnesiumstearat
+                magnesiumstearat
-                ),
+            ),
-                "Blutungen, Blutergüsse",
+            "Blutungen, Blutergüsse",
-                "Oral",
+            "Oral",
-                110
+            110,
+            new ArrayList<>()
         ));
         MedicationDao dao = DaoFactory.getInstance().createMedicationDAO();
-        Map<String, Medication> medicationsByName = new HashMap<>();
         for (Medication medication : medications) {
             dao.create(medication);
+        }
+        List<Medication> createdMedications = dao.readAll();
+        Map<String, Medication> medicationsByName = new HashMap<>();
+        for (Medication medication : createdMedications){
+            switch (medication.getName()){
+                case "Warfarin":
+                    medication.setAlternativeMedication(List.of(
+                            createdMedications.get(0),
+                            createdMedications.get(3)
+                    ));
+                    break;
+                default:
+                    break;
+            }
+            dao.update(medication);
             medicationsByName.put(medication.getName(), medication);
         }
         return medicationsByName;

src/main/java/de/hitec/nhplus/medication/AllMedicationController.java

@@ -48,6 +48,8 @@ public class AllMedicationController {
     private TableColumn<Medication, String> columnAdministrationMethod;
     @FXML
     private TableColumn<Medication, Integer> columnCurrentStock;
+    @FXML
+    public TableColumn<Medication, String> columnAlternativeMedication;
 
     private final ObservableList<Medication> medications = FXCollections.observableArrayList();
     private MedicationDao dao;
@@ -77,13 +79,29 @@ public class AllMedicationController {
                     return new SimpleStringProperty(
                             ingredients
                                     .stream()
-                                    .map(ingredient -> ingredient.getName())
+                                    .map(Ingredient::getName)
                                     .collect(Collectors.joining("\n"))
                     );
                 });
         this.columnPossibleSideEffects.setCellValueFactory(new PropertyValueFactory<>("possibleSideEffects"));
         this.columnAdministrationMethod.setCellValueFactory(new PropertyValueFactory<>("administrationMethod"));
         this.columnCurrentStock.setCellValueFactory(new PropertyValueFactory<>("currentStock"));
+        this.columnAlternativeMedication.setCellValueFactory(
+                cellData -> {
+                    Medication medication = cellData.getValue();
+                    List<Medication> alternatives = medication.getAlternativeMedication();
+                    if (alternatives.isEmpty()) {
+                        return new SimpleStringProperty("");
+                    }
+
+                    return new SimpleStringProperty(
+                            alternatives
+                                    .stream()
+                                    .map(med -> med.getName() + ", " + med.getManufacturer())
+                                    .collect(Collectors.joining("\n"))
+                    );
+                }
+        );
 
         this.tableView.setItems(this.medications);
     }

src/main/java/de/hitec/nhplus/medication/Medication.java

@@ -23,6 +23,7 @@ public class Medication {
     private final SimpleStringProperty possibleSideEffects;
     private final SimpleStringProperty administrationMethod;
     private final SimpleIntegerProperty currentStock;
+    private final SimpleListProperty<Medication> alternativeMedication;
 
     /**
      * This constructor allows instantiating a {@link Medication} object,
@@ -37,7 +38,8 @@ public class Medication {
             List<Ingredient> ingredients,
             String possibleSideEffects,
             String administrationMethod,
-            int currentStock
+            int currentStock,
+            List<Medication> alternativeMedication
     ) {
         this.name = new SimpleStringProperty(name);
         this.manufacturer = new SimpleStringProperty(manufacturer);
@@ -45,6 +47,7 @@ public class Medication {
         this.possibleSideEffects = new SimpleStringProperty(possibleSideEffects);
         this.administrationMethod = new SimpleStringProperty(administrationMethod);
         this.currentStock = new SimpleIntegerProperty(currentStock);
+        this.alternativeMedication = new SimpleListProperty<>(FXCollections.observableArrayList(alternativeMedication));
     }
 
     /**
@@ -57,7 +60,8 @@ public class Medication {
             List<Ingredient> ingredients,
             String possibleSideEffects,
             String administrationMethod,
-            int currentStock
+            int currentStock,
+            List<Medication> alternativeMedication
     ) {
         this.id = new SimpleIntegerProperty(id);
         this.name = new SimpleStringProperty(name);
@@ -66,6 +70,7 @@ public class Medication {
         this.possibleSideEffects = new SimpleStringProperty(possibleSideEffects);
         this.administrationMethod = new SimpleStringProperty(administrationMethod);
         this.currentStock = new SimpleIntegerProperty(currentStock);
+        this.alternativeMedication = new SimpleListProperty<>(FXCollections.observableArrayList(alternativeMedication));
     }
 
     public int getId() {
@@ -124,6 +129,18 @@ public class Medication {
         this.possibleSideEffects.set(possibleSideEffects);
     }
 
+    public ObservableList<Medication> getAlternativeMedication() {
+        return alternativeMedication.get();
+    }
+
+    public SimpleListProperty<Medication> alternativeMedicationProperty() {
+        return alternativeMedication;
+    }
+
+    public void setAlternativeMedication(List<Medication> alternativeMedication) {
+        this.alternativeMedication.set(FXCollections.observableArrayList(alternativeMedication));
+    }
+
     public String getAdministrationMethod() {
         return administrationMethod.get();
     }
@@ -162,6 +179,7 @@ public class Medication {
                 .add("Possible Side Effects: " + this.getPossibleSideEffects())
                 .add("Administration Method: " + this.getAdministrationMethod())
                 .add("Current Stock: " + this.getCurrentStock())
+                .add("Alternative Medication" + this.getAlternativeMedication())
                 .toString();
     }
 

src/main/java/de/hitec/nhplus/medication/MedicationListCell.java

@@ -1,7 +1,5 @@
 package de.hitec.nhplus.medication;
 
-import java.util.List;
-
 import javafx.beans.value.ObservableValue;
 import javafx.collections.FXCollections;
 import javafx.collections.ObservableList;
@@ -13,6 +11,8 @@ import javafx.scene.layout.BorderPane;
 import javafx.scene.text.Text;
 import org.controlsfx.control.SearchableComboBox;
 
+import java.util.List;
+
 /**
  * A custom implementation of the {@link ListCell} for {@link Ingredient}s.
  * This implementation contains an automatic resizing of the parent {@link ListView}.
@@ -21,20 +21,19 @@ import org.controlsfx.control.SearchableComboBox;
  */
 public class MedicationListCell extends ListCell<Medication> {
     private final Button deleteButton;
-    private SearchableComboBox<Medication> comboBox;
+    private final SearchableComboBox<Medication> comboBox;
     private static final double BUILTIN_BORDER_WIDTH = 1;
     private static final double CELL_SPACING = 4;
     private static final double CELL_PADDING = 4;
     private static final double BUTTON_PADDING_X = 8;
     private static final double BUTTON_PADDING_Y = 4;
     private final double totalSpacing;
-    private final List<Medication> allOtherMedications;
+    private boolean firstUpdate = true;
 
     public MedicationListCell(List<Medication> allOtherMedications) {
-        this.allOtherMedications = allOtherMedications;
         this.setPadding(new Insets(CELL_PADDING));
 
-        comboBox = new SearchableComboBox();
+        comboBox = new SearchableComboBox<>();
         ObservableList<Medication> list = FXCollections.observableArrayList();
         list.setAll(allOtherMedications);
         comboBox.setItems(list);
@@ -45,10 +44,10 @@ public class MedicationListCell extends ListCell<Medication> {
 
         deleteButton = new Button("-");
         deleteButton.setPadding(new Insets(
-            BUTTON_PADDING_Y,
+                BUTTON_PADDING_Y,
-            BUTTON_PADDING_X,
+                BUTTON_PADDING_X,
-            BUTTON_PADDING_Y,
+                BUTTON_PADDING_Y,
-            BUTTON_PADDING_X
+                BUTTON_PADDING_X
         ));
         deleteButton.setOnAction(event -> getListView().getItems().remove(getItem()));
 
@@ -58,34 +57,55 @@ public class MedicationListCell extends ListCell<Medication> {
         double calculatedDeleteButtonWidth = textNode.getLayoutBounds().getWidth() + BUTTON_PADDING_X * 2;
 
         totalSpacing = BUILTIN_BORDER_WIDTH * 2 // List View
-            + CELL_PADDING * 2
+                       + CELL_PADDING * 2
-            + CELL_SPACING
+                       + CELL_SPACING
-            + calculatedDeleteButtonWidth;
+                       + calculatedDeleteButtonWidth;
     }
 
+    
+    /**
+     * A Callback for use as a Listener for the {@link MedicationListCell#comboBox}.
+     */
     private void onComboBoxChange(
-        ObservableValue<? extends Medication> observableValue,
+            ObservableValue<? extends Medication> observableValue,
-        Medication oldValue,
+            Medication oldValue,
-        Medication newValue
+            Medication newValue
     ) {
+        Medication selectedMedication = comboBox.getValue();
         ListView<Medication> listView = getListView();
+
+        if (oldValue != null) {
+            listView.getItems().remove(getItem());
+            listView.getItems().add(selectedMedication);
+            setItem(selectedMedication);
+        }
+
         double max = listView.lookupAll("*")
-            .stream()
+                .stream()
-            .filter(node -> node instanceof  MedicationListCell)
+                .filter(node -> node instanceof MedicationListCell)
-            .mapToDouble(node -> getComboBoxWidth())
+                .mapToDouble(node -> comboBox.getWidth())
-            .max()
+                .max()
-            .orElse(0);
+                .orElse(0);
 
         listView.setMinWidth(max + totalSpacing);
     }
 
-
     @Override
     protected void updateItem(Medication item, boolean empty) {
         super.updateItem(item, empty);
         if (empty || item == null) {
             setGraphic(null);
         } else {
+            if (
+                    firstUpdate
+                    && comboBox.getSelectionModel().getSelectedItem() == null
+                    && item.getName() != null
+                    && comboBox.getItems().contains(item)
+            ) {
+                comboBox.getSelectionModel().select(item);
+            }
+            firstUpdate = false;
+
             BorderPane cellPane = new BorderPane();
             cellPane.setCenter(comboBox);
             cellPane.setRight(deleteButton);
@@ -94,10 +114,6 @@ public class MedicationListCell extends ListCell<Medication> {
         }
     }
 
-    private double getComboBoxWidth(){
-        return comboBox.getWidth();
-    }
-
     private ListCell comboBoxFactory(Object param) {
         return new ListCell<Medication>() {
 
@@ -105,9 +121,9 @@ public class MedicationListCell extends ListCell<Medication> {
             protected void updateItem(Medication med, boolean empty) {
                 super.updateItem(med, empty);
                 setText(
-                    empty || med == null
+                        empty || med == null
-                        ? null
+                                ? null
-                        : med.getComboBoxString()
+                                : med.getComboBoxString()
                 );
             }
         };
@@ -119,9 +135,9 @@ public class MedicationListCell extends ListCell<Medication> {
             protected void updateItem(Medication med, boolean empty) {
                 super.updateItem(med, empty);
                 setText(
-                    empty || med == null
+                        empty || med == null
-                        ? comboBox.getPromptText()
+                                ? comboBox.getPromptText()
-                        : med.getComboBoxString()
+                                : med.getComboBoxString()
                 );
             }
         };

src/main/java/de/hitec/nhplus/medication/MedicationModalController.java

@@ -4,7 +4,9 @@ import static de.hitec.nhplus.utils.Validator.*;
 
 import java.util.ArrayList;
 import java.util.List;
+import java.util.Map;
 import java.util.function.Predicate;
+import java.util.stream.Collectors;
 
 import javafx.beans.value.ChangeListener;
 import javafx.collections.FXCollections;
@@ -70,7 +72,8 @@ public class MedicationModalController {
                 new ArrayList<>(),
                 "",
                 "",
-                0
+                0,
+                new ArrayList<>()
             );
             this.buttonSave.setDisable(true);
         }
@@ -103,12 +106,17 @@ public class MedicationModalController {
      */
     private void showData() {
         ingredients.setAll(medication.getIngredients());
+        alternativeMediaction.setAll(medication.getAlternativeMedication());
+        Map<Integer, Medication> currentAlternatives = alternativeMediaction
+                .stream()
+                .collect(Collectors.toMap(Medication::getId, med -> med));
         try {
             allOtherMedications = controller.getDao().readAll();
             if (!isNewMedication) {
                 allOtherMedications = allOtherMedications
                     .stream()
                     .filter(med -> med.getId() != medication.getId())
+                        .map(med -> currentAlternatives.getOrDefault(med.getId(), med))
                     .toList();
             }
         } catch (Exception exception) {
@@ -137,6 +145,14 @@ public class MedicationModalController {
             .toList()
         );
 
+        List<Medication> meds = alternativeMediaction
+            .stream()
+            .distinct()
+            .toList();
+        this.medication.setAlternativeMedication(
+            meds
+        );
+
         if (isNewMedication) {
             controller.createMedication(medication);
         } else {
@@ -161,10 +177,11 @@ public class MedicationModalController {
         alternativeMediaction.add(new Medication(
             null,
             null,
-            List.of(),
+            new ArrayList<>(),
             null,
             null,
-            -1
+            -1,
+            new ArrayList<>()
         ));
     }
 }

src/main/java/de/hitec/nhplus/medication/database/MedicationDao.java

@@ -8,10 +8,7 @@ import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
-import java.util.ArrayList;
+import java.util.*;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
 
 /**
  * The {@link MedicationDao} is an implementation of the{@link de.hitec.nhplus.datastorage.Dao Dao}
@@ -63,36 +60,45 @@ public class MedicationDao implements Dao<Medication> {
             ingredientStatement.setString(2, ingredient.getName());
             ingredientStatement.execute();
         }
+
+        final String alternativeMedicationSQL = """
+                    INSERT INTO medication_alternative
+                    (id, alternativeId)
+                    VALUES (?, ?);
+                """;
+        for (Medication alternative : medication.getAlternativeMedication()) {
+            PreparedStatement alternativeStatement = this.connection.prepareStatement(alternativeMedicationSQL);
+            alternativeStatement.setInt(1, newId);
+            alternativeStatement.setInt(2, alternative.getId());
+            alternativeStatement.execute();
+        }
     }
 
     @Override
     public Medication read(int id) throws SQLException {
-        final String SQL = """
+        ResultSet result = getReadStatement(id).executeQuery();
-                        SELECT medication.*, medication_ingredient.id
-                        FROM medication
-                        LEFT JOIN medication_ingredient ON medication.id = medication_ingredient.id
-                        WHERE medication.id = ?
-                """;
-        PreparedStatement statement = this.connection.prepareStatement(SQL);
-        statement.setInt(1, id);
-        ResultSet result = statement.executeQuery();
         return getInstanceFromResultSet(result);
     }
 
     @Override
     public List<Medication> readAll() throws SQLException {
         final String SQL = """
-                    SELECT medication.*, medication_ingredient.name
+                    SELECT medication.*, medication_ingredient.name, medication_alternative.alternativeId
-                    FROM medication LEFT JOIN
+                    FROM medication
+                    LEFT JOIN
                     medication_ingredient ON medication.id = medication_ingredient.id
+                    LEFT JOIN
+                    medication_alternative ON medication.id = medication_alternative.id
                 """;
         ResultSet result = connection.prepareStatement(SQL).executeQuery();
 
-        List<Medication> medications = new ArrayList<>();
+        Map<Integer, Medication> medications = new HashMap<>();
         Map<Integer, List<Ingredient>> ingredientMap = new HashMap<>();
+        Map<Integer, Set<Integer>> alternativesMap = new HashMap<>();
 
         int currentMedicationId;
         int lastMedicationId = -1;
+        String latIngredient = "";
         while (result.next()) {
             currentMedicationId = result.getInt(1);
             if (currentMedicationId != lastMedicationId) {
@@ -103,27 +109,42 @@ public class MedicationDao implements Dao<Medication> {
                         new ArrayList<>(),
                         result.getString(4),
                         result.getString(5),
-                        result.getInt(6)
+                        result.getInt(6),
+                        new ArrayList<>()
                 );
-                medications.add(medication);
+                medications.put(currentMedicationId, medication);
             }
+
             List<Ingredient> ingredients = ingredientMap.computeIfAbsent(currentMedicationId, k -> new ArrayList<>());
             String ingredientName = result.getString(7);
-            if(ingredientName == null){
+            if (ingredientName != null && !latIngredient.equals(ingredientName)) {
-                continue;
+                ingredients.add(new Ingredient(ingredientName));
+                latIngredient = ingredientName;
             }
-            ingredients.add(new Ingredient(ingredientName));
+
+            Set<Integer> alternatives = alternativesMap.computeIfAbsent(currentMedicationId, k -> new HashSet<>());
+            int alternativeId = result.getInt(8);
+            if (alternativeId != 0) {
+                alternatives.add(alternativeId);
+            }
+
             lastMedicationId = currentMedicationId;
         }
-        for (Medication medication : medications) {
+        for (Medication medication : medications.values()) {
             List<Ingredient> ingredients = ingredientMap.get(medication.getId());
-            if(ingredients.isEmpty()){
+            if (ingredients.isEmpty()) {
                 continue;
             }
             medication.setIngredients(ingredientMap.get(medication.getId()));
+            Set<Integer> alternativeIds = alternativesMap.get(medication.getId());
+            List<Medication> alternatives = new ArrayList<>();
+            for (Integer alternativeId : alternativeIds) {
+                alternatives.add(medications.get(alternativeId));
+            }
+            medication.setAlternativeMedication(alternatives);
         }
 
-        return medications;
+        return medications.values().stream().toList();
     }
 
     @Override
@@ -164,6 +185,25 @@ public class MedicationDao implements Dao<Medication> {
             statement.setString(2, ingredient.getName());
             statement.execute();
         }
+
+        final String alternativeDeleteSQL = """
+                    DELETE FROM medication_alternative WHERE id = ?
+                """;
+        PreparedStatement alternativeStatement = this.connection.prepareStatement(alternativeDeleteSQL);
+        alternativeStatement.setInt(1, medication.getId());
+        alternativeStatement.executeUpdate();
+
+        final String alternativeCreateSQL = """
+                    INSERT INTO medication_alternative
+                    (id, alternativeId)
+                    VALUES (?, ?);
+                """;
+        for (Medication alternative : medication.getAlternativeMedication()) {
+            PreparedStatement statement = this.connection.prepareStatement(alternativeCreateSQL);
+            statement.setInt(1, medication.getId());
+            statement.setInt(2, alternative.getId());
+            statement.execute();
+        }
     }
 
     @Override
@@ -176,6 +216,23 @@ public class MedicationDao implements Dao<Medication> {
         preparedStatement.executeUpdate();
     }
 
+    /**
+     * @param id The ID of the database entry to read.
+     * @return A {@link PreparedStatement} to read a specific entry by its ID.
+     */
+    public PreparedStatement getReadStatement(int id) throws SQLException {
+        final String SQL = """
+                        SELECT medication.*, medication_ingredient.name, medication_alternative.alternativeId
+                        FROM medication
+                        LEFT JOIN medication_ingredient ON medication.id = medication_ingredient.id
+                        LEFT JOIN medication_alternative ON medication.id = medication_alternative.id
+                        WHERE medication.id = ?
+                """;
+        PreparedStatement statement = this.connection.prepareStatement(SQL);
+        statement.setInt(1, id);
+        return statement;
+    }
+
     /**
      * Constructs a {@link Medication} object from the {@link ResultSet} obtained after executing a database query.
      * This method is used internally to map the {@link ResultSet} data to a {@link Medication} object.
@@ -188,18 +245,40 @@ public class MedicationDao implements Dao<Medication> {
                 result.getInt(1),
                 result.getString(2),
                 result.getString(3),
-                List.of(),
+                new ArrayList<>(),
                 result.getString(4),
                 result.getString(5),
-                result.getInt(6)
+                result.getInt(6),
+                new ArrayList<>()
         );
 
         List<Ingredient> ingredients = new ArrayList<>();
+        List<Medication> alternatives = new ArrayList<>();
         while (result.next()) {
-            ingredients.add(new Ingredient(result.getString(2)));
+            String ingredientName = result.getString(7);
-
+            if (ingredientName != null) {
+                ingredients.add(new Ingredient(ingredientName));
+            }
+            int alternativeId = result.getInt(8);
+            if (alternativeId != 0) {
+                ResultSet alternativeResult = getReadStatement(alternativeId).executeQuery();
+                Medication alternativeMedication = new Medication(
+                        alternativeResult.getInt(1),
+                        alternativeResult.getString(2),
+                        alternativeResult.getString(3),
+                        new ArrayList<>(),
+                        alternativeResult.getString(4),
+                        alternativeResult.getString(5),
+                        alternativeResult.getInt(6),
+                        new ArrayList<>()
+                );
+                alternatives.add(alternativeMedication);
+            }
         }
         medication.setIngredients(ingredients);
+        medication.setAlternativeMedication(alternatives);
         return medication;
+
+
     }
 }

src/main/resources/de/hitec/nhplus/medication/database/Medication_Alternative.sql

@@ -0,0 +1,7 @@
+CREATE TABLE medication_alternative
+(
+    id   INTEGER NOT NULL ,
+    alternativeId   INTEGER NOT NULL ,
+    FOREIGN KEY (id) REFERENCES medication (id) ON DELETE CASCADE,
+    FOREIGN KEY (alternativeId) REFERENCES medication (id) ON DELETE CASCADE
+)