title: NullPointerException in JavaFX initialize in TableView
body: <p>I have this controller class for showing a database query in a TableView, but i am having error of NullPointerException with the "setCellValueFactory(new PropertyValueFactory" </p>
  
  <pre><code>package aplicativo;
  
  import java.net.URL;
  import java.util.ResourceBundle;
  
  import javafx.collections.FXCollections;
  import javafx.collections.ObservableList;
  import javafx.fxml.FXML;
  import javafx.fxml.Initializable;
  import javafx.scene.control.Button;
  import javafx.scene.control.TableColumn;
  import javafx.scene.control.TableView;
  import javafx.scene.control.TextField;
  import javafx.scene.control.cell.PropertyValueFactory;
  
  public class Controle implements Initializable{
      @FXML
      private TextField txtCampo,txtCampo2;
      @FXML
      private Button btAdicionar,btConsultar;
      @FXML
      private TableView&lt;Pessoa&gt; tabValues;
      @FXML
      private TableColumn&lt;Pessoa, Integer&gt; tbcCod;
      private TableColumn&lt;Pessoa, String&gt;tbcNome;
      ObservableList&lt;Pessoa&gt; List = FXCollections.observableArrayList();
      @FXML
      private void btAdd(){
          insertBD a = new insertBD(txtCampo.getText());
          consultaBD b = new consultaBD();
          List = b.consultaTudo();
          tabValues.setItems(List);
          txtCampo.clear();
      }
      @FXML
  
      private void btCons(){
          String tx = txtCampo2.getText();
          if(tx.isEmpty()){
  
          }else{
          consultaBD a = new consultaBD();
          a.consultaParecido(tx, "nome");
          txtCampo2.clear();
          }
      }
      @Override
      public void initialize(URL arg0, ResourceBundle arg1) {
  
          // TODO Auto-generated method stub
          tbcCod.setCellValueFactory(new PropertyValueFactory&lt;Pessoa, Integer&gt;("cod"));
          tbcNome.setCellValueFactory(new PropertyValueFactory&lt;Pessoa, String&gt;("nome"));
          tabValues.setItems(List);
          tabValues.getColumns().addAll(tbcCod,tbcNome);
      }
  }
  </code></pre>
  
  <p>The NullPointerExcepetion:</p>
  
  <pre><code>Exception in Application start method
  java.lang.reflect.InvocationTargetException
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
      at java.lang.reflect.Method.invoke(Unknown Source)
      at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(Unknown Source)
      at com.sun.javafx.application.LauncherImpl.launchApplication(Unknown Source)
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
      at java.lang.reflect.Method.invoke(Unknown Source)
      at sun.launcher.LauncherHelper$FXHelper.main(Unknown Source)
  Caused by: java.lang.RuntimeException: Exception in Application start method
      at com.sun.javafx.application.LauncherImpl.launchApplication1(Unknown Source)
      at com.sun.javafx.application.LauncherImpl.lambda$launchApplication$152(Unknown Source)
      at com.sun.javafx.application.LauncherImpl$$Lambda$50/1645995473.run(Unknown Source)
      at java.lang.Thread.run(Unknown Source)
  Caused by: javafx.fxml.LoadException: 
  /C:/Users/lucas/workspace/BDFX/bin/aplicativo/Tela.fxml
  
      at javafx.fxml.FXMLLoader.constructLoadException(Unknown Source)
      at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
      at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
      at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
      at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
      at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
      at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
      at javafx.fxml.FXMLLoader.loadImpl(Unknown Source)
      at javafx.fxml.FXMLLoader.load(Unknown Source)
      at aplicativo.Main.start(Main.java:13)
      at com.sun.javafx.application.LauncherImpl.lambda$launchApplication1$159(Unknown Source)
      at com.sun.javafx.application.LauncherImpl$$Lambda$53/1031257736.run(Unknown Source)
      at com.sun.javafx.application.PlatformImpl.lambda$runAndWait$172(Unknown Source)
      at com.sun.javafx.application.PlatformImpl$$Lambda$45/186276003.run(Unknown Source)
      at com.sun.javafx.application.PlatformImpl.lambda$null$170(Unknown Source)
      at com.sun.javafx.application.PlatformImpl$$Lambda$48/1529876784.run(Unknown Source)
      at java.security.AccessController.doPrivileged(Native Method)
      at com.sun.javafx.application.PlatformImpl.lambda$runLater$171(Unknown Source)
      at com.sun.javafx.application.PlatformImpl$$Lambda$47/237061348.run(Unknown Source)
      at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(Unknown Source)
      at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
      at com.sun.glass.ui.win.WinApplication.lambda$null$145(Unknown Source)
      at com.sun.glass.ui.win.WinApplication$$Lambda$36/2117255219.run(Unknown Source)
      ... 1 more
  Caused by: java.lang.NullPointerException
      at aplicativo.Controle.initialize(Controle.java:52)
      ... 23 more
  Exception running application aplicativo.Main
  </code></pre>
  
  <p>Any solution?</p>