java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
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时间：2020-08-13 06:57:20 来源:igfitidea点击:
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
提问by ILikeProgramming
I get a NullPointerException when I run the following program. Please note that I'm using Hibernate.
运行以下程序时出现 NullPointerException。请注意，我正在使用 Hibernate。
I can't figure out how to fix the Null Pointer error. This is the error:
我不知道如何修复空指针错误。这是错误：
Caused by: java.lang.NullPointerException
at wakiliproject.SampleController.setSettersLose(SampleController.java:22)
The KIWI_TABLE is created in the database by this class:
KIWI_TABLE 是由这个类在数据库中创建的：
import java.io.Serializable;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
@Entity(name = "KIWI_TABLE")
public class NewBeautifulKiwi implements Serializable {
@Id
@GeneratedValue
private int KiwiId;
private String Kiwi;
public int getKiwiId() {
return KiwiId;
}
public void setKiwiId(int KiwiId) {
this.KiwiId = KiwiId;
}
public String getKiwi() {
return Kiwi;
}
public void setKiwi(String Kiwi) {
this.Kiwi = Kiwi;
}
}
This is how I call the NewBeautifulKiwi to persist items into the table 'KIWI_TABLE': (partial extract of the class)
这就是我调用 NewBeautifulKiwi 将项目持久化到表“KIWI_TABLE”中的方式：（类的部分摘录）
public class SampleController implements Initializable, ControlledScreen {
@FXML
TextField KIWITextField;
@FXML
public void setSettersLose () {
NewBeautifulKiwi newBeautifulKiwi = new NewBeautifulKiwi();
newBeautifulKiwi.setKiwi(KIWITextField.getText());
SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();
Session session = sessionFactory.openSession();
session.beginTransaction();
session.save(newBeautifulKiwi);
session.getTransaction().commit();
}
More of the error:
更多错误：
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1449)
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:69)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:217)
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:170)
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:38)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:37)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92)
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35)
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92)
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:53)
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:33)
at javafx.event.Event.fireEvent(Event.java:171)
at javafx.scene.Scene$ClickGenerator.postProcess(Scene.java:3100)
at javafx.scene.Scene$ClickGenerator.access00(Scene.java:3038)
at javafx.scene.Scene$MouseHandler.process(Scene.java:3320)
at javafx.scene.Scene$MouseHandler.process(Scene.java:3151)
at javafx.scene.Scene$MouseHandler.access00(Scene.java:3106)
at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1563)
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2248)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:250)
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:173)
at java.security.AccessController.doPrivileged(Native Method)
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:292)
at com.sun.glass.ui.View.handleMouseEvent(View.java:530)
at com.sun.glass.ui.View.notifyMouse(View.java:924)
at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at com.sun.glass.ui.win.WinApplication.access0(WinApplication.java:17)
at com.sun.glass.ui.win.WinApplication.run(WinApplication.java:67)
at java.lang.Thread.run(Thread.java:744)
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:75)
at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:279)
at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1446)
... 30 more
Caused by: java.lang.NullPointerException
at wakiliproject.SampleController.setSettersLose(SampleController.java:23)
... 40 more
Thank you in advance.
先感谢您。
EDIT: The SampleController Class with everything else:
编辑：带有其他所有内容的 SampleController 类：
import java.net.URL;
import java.util.ResourceBundle;
import javafx.application.Platform;
import javafx.fxml.FXML;
import javafx.fxml.Initializable;
import javafx.scene.control.TextField;
import javafx.scene.layout.Pane;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import wakiliproject.Forms.AddNew.DB.NewBeautifulKiwi;
public class SampleController implements Initializable, ControlledScreen {
@FXML
TextField KIWITextField = null;
@FXML
public void setSettersLose () {
NewBeautifulKiwi newBeautifulKiwi = new NewBeautifulKiwi();
newBeautifulKiwi.setKiwi(KIWITextField.getText());
SessionFactory sessionFactory = new Configuration().configure().buildSessionFactory();
Session session = sessionFactory.openSession();
session.beginTransaction();
session.save(newBeautifulKiwi);
session.getTransaction().commit();
}
ScreensController myController;
// Initializes the controller class.
@Override
public void initialize(URL url, ResourceBundle rb) {
// TODO
}
@Override
public void setScreenParent(ScreensController screenParent) {
myController = screenParent;
}
@FXML
public void windowClose() {
Platform.exit();
}
// Pages
@FXML
private void goToClients() {
myController.setScreen(WakiliProject.clientsID);
}
@FXML
private void goToMatters() {
myController.setScreen(WakiliProject.mattersID);
}
@FXML
private void goToEvents() {
myController.setScreen(WakiliProject.eventsID);
}
@FXML
private void goToFirmProfileView() {
myController.setScreen(WakiliProject.firmProfileID);
}
// Hover menus
@FXML
Pane clientAccountsHoverMenu;
@FXML
private void clientAccountsHover() {
clientAccountsHoverMenu.setVisible(true);
}
@FXML
private void clientAccountsHoverOut() {
clientAccountsHoverMenu.setVisible(false);
}
// Hidden Panes
@FXML
Pane notesHomePane;
@FXML
Pane navItems;
@FXML
Pane mainHome;
@FXML
Pane homeContentDisplay;
@FXML
private void notesHomePaneShow() {
notesHomePane.setVisible(true);
mainHome.setVisible(false);
}
@FXML
private void goToHome() {
notesHomePane.setVisible(false);
mainHome.setVisible(true);
}
@FXML
private void navItemsShow() {
navItems.setVisible(true);
homeContentDisplay.setVisible(false);
}
@FXML
private void goToHomeFronNavAll() {
navItems.setVisible(false);
homeContentDisplay.setVisible(true);
}
}
采纳答案by aljipa
So since the line of interest is newBeautifulKiwi.setKiwi(KIWITextField.getText());and taking into account that newBeautifulKiwican never be null (it has just been created using default constructor) it's KIWITextFieldthat is null and thus not inject properly. make sure the id of this element in .fxml file exactlymatches this field's name (I'd made it private).
因此，由于感兴趣的线是newBeautifulKiwi.setKiwi(KIWITextField.getText());并且考虑到它newBeautifulKiwi永远不会为空（它刚刚使用默认构造函数创建）它KIWITextField是空的，因此不能正确注入。确保 .fxml 文件中此元素的 id与此字段的名称完全匹配（我已将其设为私有）。
Most probable cause is setSettersLoseannotated with @FXML. Check the similar thread.
最可能的原因是setSettersLose用@FXML 注释的。检查类似的线程。
