implemented deleteion without validataion

src/main/java/at/ionas999/questioncatalog/controller/ViewController.java

@@ -1,27 +1,87 @@
 package at.ionas999.questioncatalog.controller;
 
 import at.ionas999.questioncatalog.model.Question;
+import at.ionas999.questioncatalog.model.QuestionCatalog;
+import at.ionas999.questioncatalog.services.QuestionCatalogService;
 import at.ionas999.questioncatalog.services.QuestionService;
+import at.ionas999.questioncatalog.services.ServiceBase;
+import javafx.collections.FXCollections;
+import javafx.collections.ObservableList;
+import javafx.event.ActionEvent;
 import javafx.fxml.FXML;
-import javafx.scene.control.Button;
+import javafx.scene.control.*;
-import javafx.scene.control.ListView;
-import javafx.scene.control.TextArea;
-import javafx.scene.control.TextField;
 
 import java.sql.SQLException;
+import java.util.ArrayList;
 import java.util.List;
 
 public class ViewController {
-    public Button editButton;
+    @FXML
-    public Button deleteButton;
+    private ComboBox selectBox;
-    public TextField answerField;
+    @FXML
-    public ListView questionListView;
+    private Button editButton;
-    public TextField questionField;
+    @FXML
+    private Button deleteButton;
+    @FXML
+    private TextField answerField;
+    @FXML
+    private ListView questionListView;
+    @FXML
+    private TextField questionField;
 
+    private Question currentQuestion = null;
+    private ObservableList<QuestionCatalog> catalogs;
+    private ObservableList<Question> questions;
 
     @FXML
     private void initialize() throws SQLException {
-        List<Question> questions = QuestionService.GetQuestionsFromCatalog(1);
+        this.catalogs = FXCollections.observableList(QuestionCatalogService.GetCatalogsWithoutQuestions());
-        System.out.println(questions);
+        selectBox.setItems(catalogs);
+        addObserverToSelectBox();
+        addListenerToListView();
+    }
+
+    private void addListenerToListView() {
+        questionListView.getSelectionModel().selectedItemProperty().addListener((observableValue, oldValue, newValue) -> {
+            currentQuestion = (Question) newValue;
+            if (newValue != null) {
+                Question q = (Question) newValue;
+                questionField.setText(q.getQuestion());
+                answerField.setText(q.getAnswer());
+            }
+        });
+    }
+
+    private void addObserverToSelectBox() {
+        selectBox.getSelectionModel().selectedItemProperty().addListener((observable, oldValue, newValue) -> {
+            if (newValue == null) {
+                return;
+            }
+
+            try {
+                setQuestionListView(((QuestionCatalog) newValue).getId());
+            } catch (SQLException e) {
+                throw new RuntimeException(e);
+            }
+        });
+    }
+
+    private void setQuestionListView(int catalogId) throws SQLException {
+        this.questions = FXCollections.observableList(QuestionService.GetQuestionsFromCatalog(catalogId));
+        questionListView.setItems(questions);
+    }
+
+
+    @FXML
+    private void deleteQuestion(ActionEvent actionEvent) {
+        questions.remove(currentQuestion);
+        QuestionService.DeleteQuestion(currentQuestion.getId());
+        this.questionListView.refresh();
+        this.currentQuestion = null;
+    }
+
+    @FXML
+    private void editQuestion(ActionEvent actionEvent) {
+
     }
 }

src/main/java/at/ionas999/questioncatalog/model/Question.java

@@ -32,4 +32,17 @@ public class Question {
     public void setAnswer(String answer) {
         this.answer = answer;
     }
+
+    public void setQuestionCatalogId(int questionCatalogId) {
+        this.questionCatalogId = questionCatalogId;
+    }
+
+    public int getId()
+    {
+        return id;
+    }
+    @Override
+    public String toString() {
+        return question;
+    }
 }

src/main/java/at/ionas999/questioncatalog/model/QuestionCatalog.java

@@ -11,7 +11,8 @@ public class QuestionCatalog {
     private ArrayList<Question> questions;
     private String name;
 
-    public QuestionCatalog(String name, ArrayList<Question> questions) {
+    public QuestionCatalog(int id, String name, ArrayList<Question> questions) {
+        this.id = id;
         this.name = name;
         this.questions = questions;
     }
@@ -20,8 +21,20 @@ public class QuestionCatalog {
         return FXCollections.observableList(questions);
     }
 
+    public void setQuestions(ArrayList<Question> questions){
+        this.questions = questions;
+    }
+
+    public int getId(){
+        return this.id;
+    }
+
     public String getName() {
         return name;
     }
 
+    @Override
+    public String toString() {
+        return this.getName();
+    }
 }

src/main/java/at/ionas999/questioncatalog/services/QuestionCatalogService.java

@@ -0,0 +1,75 @@
+package at.ionas999.questioncatalog.services;
+
+import at.ionas999.questioncatalog.model.Question;
+import at.ionas999.questioncatalog.model.QuestionCatalog;
+
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.List;
+
+public class QuestionCatalogService {
+    public static boolean AddQuestionCatalogToDb(QuestionCatalog catalog) throws SQLException {
+        try (Connection connection = ServiceBase.GetJDBCConnection()) {
+            String insertStmt = "insert into QUESTIONCATALOG (NAME) VALUES (?)";
+
+            try (PreparedStatement statement = connection.prepareStatement(insertStmt)) {
+                statement.setString(2, catalog.getName());
+                statement.execute();
+            }
+        }
+        int id = GetLastInsertedCatalogWithoutQuestions(catalog.getName()).getId();
+        for(Question q : catalog.getQuestions()) {
+            q.setQuestionCatalogId(id);
+            QuestionService.AddQuestionToDb(q);
+        }
+
+        return true;
+    }
+
+
+    public static QuestionCatalog GetLastInsertedCatalogWithoutQuestions(String name) throws SQLException {
+        String stmtString = "select id, name from QUESTIONCATALOG order by ID desc fetch first row only";
+        QuestionCatalog catalog;
+        try (Connection connection = ServiceBase.GetJDBCConnection()) {
+
+            try (PreparedStatement statement = connection.prepareStatement(stmtString)) {
+                ResultSet rs = statement.executeQuery();
+                List<Question> questions = new ArrayList<Question>();
+                rs.next();
+                catalog = new QuestionCatalog(
+                        rs.getInt(1),
+                        rs.getString(2),
+                        null
+                );
+
+            }
+        }
+        return catalog;
+    }
+
+    public static ArrayList<QuestionCatalog> GetCatalogsWithoutQuestions() throws SQLException {
+        String stmtString = "select id, name from QUESTIONCATALOG";
+
+        try (Connection connection = ServiceBase.GetJDBCConnection()) {
+
+            try (PreparedStatement statement = connection.prepareStatement(stmtString)) {
+                ResultSet rs = statement.executeQuery();
+                ArrayList<QuestionCatalog> catalogs = new ArrayList<>();
+
+                while (rs.next()) {
+                    QuestionCatalog catalog = new QuestionCatalog(
+                            rs.getInt(1),
+                            rs.getString(2),
+                            null
+                    );
+                    catalogs.add(catalog);
+                }
+
+                return catalogs;
+            }
+        }
+    }
+}

src/main/java/at/ionas999/questioncatalog/services/QuestionService.java

@@ -26,7 +26,7 @@ public class QuestionService {
         return true;
     }
 
-    public static List<Question> GetQuestionsFromCatalog(int catalogId) throws SQLException {
+    public static ArrayList<Question> GetQuestionsFromCatalog(int catalogId) throws SQLException {
         String stmtString = "select id, questionCatalogId, question, answer from Question where questionCatalogId = ?";
 
         try(Connection connection = ServiceBase.GetJDBCConnection()){
@@ -34,7 +34,7 @@ public class QuestionService {
             try (PreparedStatement statement = connection.prepareStatement(stmtString)){
                 statement.setInt(1, catalogId);
                 ResultSet rs = statement.executeQuery();
-                List<Question> questions = new ArrayList<Question>();
+                ArrayList<Question> questions = new ArrayList<Question>();
 
                 while (rs.next()){
                     Question question = new Question(
@@ -50,4 +50,20 @@ public class QuestionService {
             }
         }
     }
+
+    public static boolean DeleteQuestion(int id){
+        try(Connection connection = ServiceBase.GetJDBCConnection()){
+            String insertStmt = "delete from QUESTION where ID = ?";
+
+            try (PreparedStatement statement = connection.prepareStatement(insertStmt)){
+                statement.setInt(1, id);
+                statement.execute();
+            }
+        }
+        catch (SQLException _){
+            return false;
+        }
+
+        return true;
+    }
 }

src/main/java/at/ionas999/questioncatalog/services/ServiceBase.java

@@ -20,7 +20,7 @@ public abstract class ServiceBase {
                     create table QuestionCatalog
                     (
                         id INT PRIMARY KEY GENERATED ALWAYS AS IDENTITY (START WITH 1, INCREMENT BY 1),
-                        name varchar(10) not null
+                        name varchar(10) not null unique
                     )
                     """;
             try (Statement stmt = connection.createStatement()) {

src/main/resources/at/ionas999/questioncatalog/view.fxml

@@ -7,6 +7,15 @@
             fx:controller="at.ionas999.questioncatalog.controller.ViewController"
             prefHeight="400.0" prefWidth="600.0">
 
+    <top>
+        <HBox alignment="TOP_RIGHT" spacing="10.0">
+            <padding>
+                <Insets top="10.0" right="10.0" bottom="0.0" left="10.0"/>
+            </padding>
+            <ComboBox fx:id="selectBox" promptText="Select an Catalog" />
+        </HBox>
+    </top>
+
     <left>
         <ListView fx:id="questionListView" prefWidth="200.0" />
     </left>
@@ -19,8 +28,8 @@
             <TextField fx:id="questionField" editable="false" />
             <TextField fx:id="answerField" promptText="Answer" editable="false" />
             <HBox spacing="10.0" alignment="BOTTOM_RIGHT">
-                <Button fx:id="deleteButton" text="Delete" />
+                <Button fx:id="deleteButton" onAction="#deleteQuestion" text="Delete" />
-                <Button fx:id="editButton" text="Edit" />
+                <Button fx:id="editButton" text="Edit" onAction="#editQuestion"   />
             </HBox>
         </VBox>
     </center>