clean up

src/main/java/de/thdeg/grademanager/gui/CourseModificationController.java

@@ -13,8 +13,6 @@ import javafx.scene.control.*;
 import java.io.IOException;
 import java.util.Optional;
 
-import static de.thdeg.grademanager.gui.CoursesOfStudyDetailsController.courseList;
-
 public class CourseModificationController {
     @FXML
     protected ComboBox<BachelorSemester> bachelorSemesterComboBox;

src/main/java/de/thdeg/grademanager/gui/CoursesOfStudyDetailsController.java

 package de.thdeg.grademanager.gui;
 
 import de.thdeg.grademanager.model.Course;
-import de.thdeg.grademanager.model.CoursesOfStudy;
 import javafx.collections.FXCollections;
 import javafx.collections.ObservableList;
 import javafx.event.ActionEvent;
 import javafx.fxml.FXML;
 import javafx.scene.control.ListView;
-import javafx.scene.control.TextField;
 
 import java.io.IOException;
 
 public class CoursesOfStudyDetailsController {
-
-
-    @FXML
-    protected TextField courses;
-
     @FXML
     protected ListView<Course> courseListView;
 

src/main/java/de/thdeg/grademanager/gui/MainController.java

@@ -6,13 +6,8 @@ import javafx.collections.FXCollections;
 import javafx.collections.ObservableList;
 import javafx.event.ActionEvent;
 import javafx.fxml.FXML;
-import javafx.fxml.FXMLLoader;
 import javafx.scene.control.ComboBox;
 
-import javafx.scene.*;
-import javafx.scene.Node;
-import javafx.stage.*;
-
 import java.io.IOException;
 
 public class MainController {
@@ -33,11 +28,6 @@ public class MainController {
         }
     }
 
-    @FXML
-    protected void switchToMain(ActionEvent event) throws IOException {
-        SwitchWindowHelper.switchTo("Main", event);
-    }
-
     @FXML
     protected void switchToStudentDetails(ActionEvent event) throws IOException {
         SwitchWindowHelper.switchTo("Student Details", event);

src/main/java/de/thdeg/grademanager/gui/StudentDetailsController.java

 package de.thdeg.grademanager.gui;
 
 import de.thdeg.grademanager.model.CoursesOfStudy;
-import de.thdeg.grademanager.model.Student;
 import javafx.event.ActionEvent;
 import javafx.fxml.FXML;
 import javafx.scene.control.ComboBox;
@@ -9,7 +8,6 @@ import javafx.scene.control.ComboBox;
 import java.io.IOException;
 
 import static de.thdeg.grademanager.gui.MainController.coursesOfStudyList;
-import static de.thdeg.grademanager.gui.MainController.studentList;
 
 public class StudentDetailsController {