GWT/JAVA 未捕获异常转义
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时间：2020-10-30 15:29:38 来源:igfitidea点击:
GWT/JAVA Uncaught exception escaped
提问by Aegis
I have got a problem with my code and i cant seem to fix it. I want to add some customer data to a array list in java/GWT when submitting a button.
我的代码有问题，我似乎无法修复它。我想在提交按钮时将一些客户数据添加到 java/GWT 中的数组列表中。
the form from which i add the data.
我从中添加数据的表单。
ok.addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
if (!voornaamTB.getText().equalsIgnoreCase("") && !achternaamTB.getText().equalsIgnoreCase("") && !emailTB.getText().equalsIgnoreCase("") && !geboortedatumTB.getText().equalsIgnoreCase("")) {
boolean addVG;
System.out.println(voornaamTB.getText());
System.out.println(tussenvoegselTB.getText());
System.out.println(achternaamTB.getText());
System.out.println(emailTB.getText());
System.out.println(geboortedatumTB.getText());
--> the error is generated here addVG = VGC.addVakantieganger(voornaamTB.getText(), tussenvoegselTB.getText(), achternaamTB.getText(), emailTB.getText(), geboortedatumTB.getText());
if (addVG) {
Window.alert("Vakantieganger toegevoegd.");
} else {
Window.alert("Vakantieganger niet toegevoegd.");
}
} else {
voornaamTB.addStyleName("invalide-TextBox");
tussenvoegselTB.addStyleName("invalide-TextBox");
achternaamTB.addStyleName("invalide-TextBox");
emailTB.addStyleName("invalide-TextBox");
geboortedatumTB.addStyleName("invalide-TextBox");
}
}
});
the controller class.
控制器类。
import java.util.ArrayList;
import com.vakantievibes.client.domein.Vakantieganger;
public class VakantiegangerController {
private String msg;
private ArrayList<Vakantieganger> vakantiegangers = new ArrayList<Vakantieganger>();
public VakantiegangerController(){
}
@SuppressWarnings("static-access")
public boolean heeftVakantieganger(String email) {
boolean result = false;
for (Vakantieganger v : vakantiegangers) {
if (v.getEmail().equalsIgnoreCase(email)){
result = true;
}
}
return result;
}
public boolean addVakantieganger(String voornaam, String tussenvoegsel, String achternaam, String email, String geboortedatum) {
//boolean result = false;
//if (!heeftVakantieganger(email)) {
Vakantieganger v = new Vakantieganger(voornaam, tussenvoegsel, achternaam, email, geboortedatum);
vakantiegangers.add(v);
boolean result = true;
System.out.println("klant toegevoegd");
//}
return result;
}
}
with the methode addVakantieganger it should add the data to the arraylist. but it doesn't seem to do that it should then report true back to the form. the !heeftVakantieganger(email) should check if the person is already in the array list but is disabled now for testing purpose's
使用 addVakantieganger 方法，它应该将数据添加到数组列表中。但它似乎并没有这样做，然后它应该向表单报告 true。!heeftVakantieganger(email) 应该检查这个人是否已经在数组列表中，但现在为了测试目的而被禁用
the errors i recieve in eclipse.
我在 eclipse 中收到的错误。
14:17:03.207 [ERROR] [vakantie_vibes] Uncaught exception escaped
com.google.gwt.event.shared.UmbrellaException: One or more exceptions caught, see full set in UmbrellaException#getCauses
at com.google.gwt.event.shared.HandlerManager.fireEvent(HandlerManager.java:129)
at com.google.gwt.user.client.ui.Widget.fireEvent(Widget.java:124)
at com.google.gwt.event.dom.client.DomEvent.fireNativeEvent(DomEvent.java:116)
at com.google.gwt.user.client.ui.Widget.onBrowserEvent(Widget.java:172)
at com.google.gwt.user.client.DOM.dispatchEventImpl(DOM.java:1321)
at com.google.gwt.user.client.DOM.dispatchEvent(DOM.java:1277)
at sun.reflect.GeneratedMethodAccessor19.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:167)
at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessagesWhileWaitingForReturn(BrowserChannelServer.java:326)
at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:207)
at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:132)
at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:561)
at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:269)
at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91)
at com.google.gwt.core.client.impl.Impl.apply(Impl.java)
at com.google.gwt.core.client.impl.Impl.entry0(Impl.java:214)
at sun.reflect.GeneratedMethodAccessor16.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:167)
at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:281)
at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:531)
at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:352)
at java.lang.Thread.run(Thread.java:679)
Caused by: java.lang.NullPointerException: null
at com.vakantievibes.client.GUI.FormToevoegenVakantieganger.onClick(FormToevoegenVakantieganger.java:153)
at com.google.gwt.event.dom.client.ClickEvent.dispatch(ClickEvent.java:54)
at com.google.gwt.event.dom.client.ClickEvent.dispatch(ClickEvent.java:1)
at com.google.gwt.event.shared.GwtEvent.dispatch(GwtEvent.java:1)
at com.google.web.bindery.event.shared.SimpleEventBus.doFire(SimpleEventBus.java:193)
at com.google.web.bindery.event.shared.SimpleEventBus.fireEvent(SimpleEventBus.java:88)
at com.google.gwt.event.shared.HandlerManager.fireEvent(HandlerManager.java:127)
at com.google.gwt.user.client.ui.Widget.fireEvent(Widget.java:124)
at com.google.gwt.event.dom.client.DomEvent.fireNativeEvent(DomEvent.java:116)
at com.google.gwt.user.client.ui.Widget.onBrowserEvent(Widget.java:172)
at com.google.gwt.user.client.DOM.dispatchEventImpl(DOM.java:1321)
at com.google.gwt.user.client.DOM.dispatchEvent(DOM.java:1277)
at sun.reflect.GeneratedMethodAccessor19.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:167)
at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessagesWhileWaitingForReturn(BrowserChannelServer.java:326)
at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:207)
at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:132)
at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:561)
at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:269)
at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91)
at com.google.gwt.core.client.impl.Impl.apply(Impl.java)
at com.google.gwt.core.client.impl.Impl.entry0(Impl.java:214)
at sun.reflect.GeneratedMethodAccessor16.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:616)
at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)
at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)
at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:167)
at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:281)
at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:531)
at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:352)
at java.lang.Thread.run(Thread.java:679)
回答by Peter Knego
You get a NullPointerException. This happens because you are using a reference which is null. In your case this is one of the fields in the line that you marked.
你得到一个NullPointerException. 发生这种情况是因为您使用的是null. 在您的情况下，这是您标记的行中的字段之一。
Use a debugger, put a breakpoint on that line, and inspect which field in null.
使用调试器，在该行上放置一个断点，然后检查null.
回答by Aaron Digulla
Since you use all the variables, only VGCcan be nullat this time.
既然你使用了所有的变量，VGC就只能null在这个时候了。
But I suspect this is a class name. My first guess is that the type VGCis part of the server API and not of the client API or something along these lines.
但我怀疑这是一个类名。我的第一个猜测是该类型VGC是服务器 API 的一部分，而不是客户端 API 或类似的东西。
