Added first sql-queries into the SimpleDatabaseManager.java (Still failing / Red Errors)

src/main/java/hhn/temp/project/provider/SimpleDatabaseManager.java

@@ -1,34 +1,75 @@
 package hhn.temp.project.provider;
 
+import hhn.temp.project.Task;
+import hhn.temp.project.TaskState;
 import jdk.jshell.spi.ExecutionControl;
 
-import java.io.File;
 import java.io.IOException;
-import java.nio.file.Files;
-import java.nio.file.Path;
 import java.sql.Connection;
 import java.sql.DriverManager;
+import java.sql.PreparedStatement;
 import java.sql.SQLException;
 import java.util.Collection;
-import java.util.List;
 
 public class SimpleDatabaseManager<E> implements DatabaseManager<E> {
 
   private Connection connection;
 
-  @Override
-  public void saveObjects(Collection<E> objects) {
-
+  private enum QueryMode {
+    SELECT, INSERT, DELETE, UPDATE
   }
 
+  private int taskStateToInt(TaskState taskState) {
+    return (taskState == TaskState.FINISHED) ? 1 : 0;
+  }
+
+  private TaskState intToTaskState(int i) {
+    if (i < 0 || i > 1) {
+      throw new IllegalArgumentException("Integer may only bet 0 or 1");
+    }
+
+    return (i == 1) ? TaskState.FINISHED : TaskState.IN_PROGRESS;
+  }
+
+  private String getQuery(QueryMode query) throws IOException {
+    String queryString = null;
+
+    switch (query) {
+      case INSERT -> queryString = "INSERT INTO Task (name, description, workerid, taskstate) VALUES (?, ?, ?, ?)";
+      case UPDATE -> queryString = "UPDATE Task SET name = ?, description = ?, taskstate = ? WHERE taskid = ?";
+      case DELETE -> queryString = "DELETE FROM Task WHERE taskid = ?";
+      case SELECT -> queryString = "SELECT * FROM Task WHERE workerid = ?";
+    }
+
+    return queryString;
+  }
+
+  @Override
+  public void saveObjects(Collection<E> objects) throws IOException, SQLException {
+    for (E obj : objects) {
+      saveObject(obj);
+    }
+  }
+
+
   @Override
   public Collection<E> getObjects() throws ExecutionControl.NotImplementedException {
     throw new ExecutionControl.NotImplementedException("Not Implemented!");
   }
 
   @Override
-  public void saveObject(E object) throws ExecutionControl.NotImplementedException {
-    throw new ExecutionControl.NotImplementedException("Not Implemented!");
+  public void saveObject(E object) throws IOException, SQLException {
+    String query = getQuery(QueryMode.INSERT);
+
+    if (object instanceof Task task) {
+      try (PreparedStatement ps = connection.prepareStatement(query)) {
+        ps.setInt(1, task.getTaskId());
+        ps.setString(2, task.getName());
+        ps.setString(3, task.getDescription());
+        ps.setInt(4, task.getWorkerId());
+        ps.setInt(5, taskStateToInt(task.getTaskState()));
+      }
+    }
   }
 
   @Override