GWT Multiple Modules causes '$wnd.alert is not a function'

I am investigating adding GWT to an existing Spring MVC project. I successfully went through a tutorial using spring4gwt and got communication running between the client entry point and the service.

I added a new module in eclipse and left as the hello world default. Now when I press any buttons (either the new hello world button, or one from the previous example) I get a stacktrace.

To add the additional entrypoint I just added the extra script include.

What is causing this? do I need to add entrypoint modules to my project in a different way?

Here is the cause.

Caused by: com.google.gwt.core.client.JavaScriptException: (TypeError): $wnd.alert is not a function
 fileName: LOCALHOST
 lineNumber: 146
 stack: ("Hello, GWT World!")@LOCALHOST:146
@:0
(null,458830,[object MouseEvent],[object HTMLButtonElement],[object GWTJavaObject])@LOCALHOST/clariti-gwt/alert/hosted.html?alert:56
([object MouseEvent])@LOCALHOST:38
((function (evt) {var listener, curElem = this;while (curElem && !(listener = curElem.__listener)) {curElem = curElem.parentNode;}if (curElem && curElem.nodeType != 1) {curElem = null;}if (listener) {if (__gwt_makeJavaInvoke(1)(null, 393334, listener)) {__gwt_makeJavaInvoke(3)(null, 458830, evt, curElem, listener);}}}),[object HTMLButtonElement],[object Object])@LOCALHOST:18
@:0
(null,106,(function (evt) {var listener, curElem = this;while (curElem && !(listener = curElem.__listener)) {curElem = curElem.parentNode;}if (curElem && curElem.nodeType != 1) {curElem = null;}if (listener) {if (__gwt_makeJavaInvoke(1)(null, 393334, listener)) {__gwt_makeJavaInvoke(3)(null, 458830, evt, curElem, listener);}}}),[object HTMLButtonElement],[object Object])@LOCALHOST/clariti-gwt/alert/hosted.html?alert:56
([object MouseEvent])@LOCALHOST:43


17:04:32.466 [ERROR] [alert] 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.SimpleEventBus.doFire(SimpleEventBus.java:214)
    at com.google.gwt.event.shared.SimpleEventBus.fireEvent(SimpleEventBus.java:103)
    at com.google.gwt.event.shared.HandlerManager.fireEvent(HandlerManager.java:96)
    at com.google.gwt.user.client.ui.Widget.fireEvent(Widget.java:107)
    at com.google.gwt.event.dom.client.DomEvent.fireNativeEvent(DomEvent.java:116)
    at com.google.gwt.user.client.ui.Widget.onBrowserEvent(Widget.java:155)
    at com.google.gwt.user.client.DOM.dispatchEventImpl(DOM.java:1308)
    at com.google.gwt.user.client.DOM.dispatchEvent(DOM.java:1264)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    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:157)
    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:126)
    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.GeneratedMethodAccessor27.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    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:157)
    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:619)
Caused by: com.google.gwt.core.client.JavaScriptException: (TypeError): $wnd.alert is not a function
 fileName: LOCALHOST
 lineNumber: 146
 stack: ("Hello, GWT World!")@LOCALHOST:146
@:0
(null,458830,[object MouseEvent],[object HTMLButtonElement],[object GWTJavaObject])@LOCALHOST/clariti-gwt/alert/hosted.html?alert:56
([object MouseEvent])@LOCALHOST:38
((function (evt) {var listener, curE开发者_如何学编程lem = this;while (curElem && !(listener = curElem.__listener)) {curElem = curElem.parentNode;}if (curElem && curElem.nodeType != 1) {curElem = null;}if (listener) {if (__gwt_makeJavaInvoke(1)(null, 393334, listener)) {__gwt_makeJavaInvoke(3)(null, 458830, evt, curElem, listener);}}}),[object HTMLButtonElement],[object Object])@LOCALHOST:18
@:0
(null,106,(function (evt) {var listener, curElem = this;while (curElem && !(listener = curElem.__listener)) {curElem = curElem.parentNode;}if (curElem && curElem.nodeType != 1) {curElem = null;}if (listener) {if (__gwt_makeJavaInvoke(1)(null, 393334, listener)) {__gwt_makeJavaInvoke(3)(null, 458830, evt, curElem, listener);}}}),[object HTMLButtonElement],[object Object])@LOCALHOST/clariti-gwt/alert/hosted.html?alert:56
([object MouseEvent])@LOCALHOST:43
    at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:237)
    at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:126)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:561)
    at com.google.gwt.dev.shell.ModuleSpace.invokeNativeVoid(ModuleSpace.java:289)
    at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeVoid(JavaScriptHost.java:107)
    at com.google.gwt.user.client.Window.alert(Window.java)
    at com.energyintellect.alert.client.AlertView$1.onClick(AlertView.java:23)
    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.SimpleEventBus.doFire(SimpleEventBus.java:204)
    at com.google.gwt.event.shared.SimpleEventBus.fireEvent(SimpleEventBus.java:103)
    at com.google.gwt.event.shared.HandlerManager.fireEvent(HandlerManager.java:96)
    at com.google.gwt.user.client.ui.Widget.fireEvent(Widget.java:107)
    at com.google.gwt.event.dom.client.DomEvent.fireNativeEvent(DomEvent.java:116)
    at com.google.gwt.user.client.ui.Widget.onBrowserEvent(Widget.java:155)
    at com.google.gwt.user.client.DOM.dispatchEventImpl(DOM.java:1308)
    at com.google.gwt.user.client.DOM.dispatchEvent(DOM.java:1264)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    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:157)
    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:126)
    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.GeneratedMethodAccessor27.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    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:157)
    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:619)

You can try below sample example..

It works..

public class JSNITest  {


public void test() {
    setShowTrigger(this);
}

public void runApp() {
    SC.say("I am called...");
}

public native void setShowTrigger(JSNITest obj)/*-{
$wnd.alert('I am a GWT JSNI function');
$wnd.showBlueApp = function () {
obj.@com.example.client.JSNITest::runApp()();

};

}-*/;

}