HtmlUnit异常
我无法理解此HTMLUnit异常的含义。当我在网页上的链接上调用click（）时会发生这种情况。
I am having trouble understanding the meaning of this HTMLUnit Exception. It happens when I call click() on a link on a webpage.
Exception class=[net.sourceforge.htmlunit.corejs.javascript.WrappedException]
com.gargoylesoftware.htmlunit.ScriptException: Wrapped com.gargoylesoftware.htmlunit.ScriptException: TypeError: Cannot read property "offsetWidth" from null (http://webapps6.doc.state.nc.us/opi/scripts/DHTMLmessages.js#95) (javascript url#297)
at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:534)
at net.sourceforge.htmlunit.corejs.javascript.Context.call(Context.java:537)
at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.call(ContextFactory.java:538)
at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:432)
at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine.execute(JavaScriptEngine.java:407)
at com.gargoylesoftware.htmlunit.html.HtmlPage.executeJavaScriptIfPossible(HtmlPage.java:965)
at com.gargoylesoftware.htmlunit.html.HtmlAnchor.doClickAction(HtmlAnchor.java:87)
at com.gargoylesoftware.htmlunit.html.HtmlAnchor.doClickAction(HtmlAnchor.java:121)
at com.gargoylesoftware.htmlunit.html.HtmlElement.click(HtmlElement.java:1329)
at com.gargoylesoftware.htmlunit.html.HtmlElement.click(HtmlElement.java:1288)
at com.gargoylesoftware.htmlunit.html.HtmlElement.click(HtmlElement.java:1257)
at testapp.TestApp.main(TestApp.java:61)
Caused by: net.sourceforge.htmlunit.corejs.javascript.WrappedException: Wrapped com.gargoylesoftware.htmlunit.ScriptException: TypeError: Cannot read property "offsetWidth" from null (http://webapps6.doc.state.nc.us.js#95) (javascript url#297)
at net.sourceforge.htmlunit.corejs.javascript.Context.throwAsScriptRuntimeEx(Context.java:1802)
at net.sourceforge.htmlunit.corejs.javascript.MemberBox.invoke(MemberBox.java:196)
at net.sourceforge.htmlunit.corejs.javascript.FunctionObject.call(FunctionObject.java:479)
at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpretLoop(Interpreter.java:1701)
at net.sourceforge.htmlunit.corejs.javascript.Interpreter.interpret(Interpreter.java:854)
at net.sourceforge.htmlunit.corejs.javascript.InterpretedFunction.call(InterpretedFunction.java:164)
at net.sourceforge.htmlunit.corejs.javascript.ContextFactory.doTopCall(ContextFactory.java:429)
at com.gargoylesoftware.htmlunit.javascript.HtmlUnitContextFactory.doTopCall(HtmlUnitContextFactory.java:267)
at net.sourceforge.htmlunit.corejs.javascript.ScriptRuntime.doTopCall(ScriptRuntime.java:3183)
at net.sourceforge.htmlunit.corejs.javascript.InterpretedFunction.exec(InterpretedFunction.java:175)
at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$5.doRun(JavaScriptEngine.java:423)
at com.gargoylesoftware.htmlunit.javascript.JavaScriptEngine$HtmlUnitContextAction.run(JavaScriptEngine.java:528)
... 11 more
当您单击并且此链接调用另一个页面时，htmlUnit在导航期间的异常可能非常详细。如果你点击你的浏览器并打开控制台，可能会看到那些错误，缺少链接或图像，调用脚本的错误..
When you click and this link call another page, htmlUnit can be very verbose on exceptions during navigation. If you click on your browser and open the console, probably will see those errors, missing links or images, errors on calling scripts..
那些不是必需的Javascript问题HtmlUnit。
Those are not necessary Javascript issues with HtmlUnit.
就像我在这里说的那样 HtmlUnit不创建HtmlPage对象您可以设置或修改htmlUnit以防止不必要的日志。你也可以设置log4j并禁用一些例外。
Like I said here HtmlUnit not creating HtmlPage object you can set or modify htmlUnit to prevent unecessary logs. You can also setup log4j and disable some exceptions.
所以我们使用这些选项来保持html navegating而不会停止我们使用的第一个错误/问题：
So we use those options to keep html navegating without stoping on first error/problem we use :
webClient.getOptions().setThrowExceptionOnScriptError(false);
webClient.getOptions().setThrowExceptionOnFailingStatusCode(false);
您还可以实现空类来阻止htmlUnity在控制台上详细说明css / javaScript错误： / p>
You can also implement empty classes to stop htmlUnity go verbose on console about css/javaScript errors with:
webClient.setCssErrorHandler(new SilentCssErrorHandler());
webClient.setJavaScriptErrorListener(new JavaScriptErrorListener(){});
小样本测试案例：
@Test
public void TestCall() throws FailingHttpStatusCodeException, MalformedURLException, IOException {
WebClient webClient = new WebClient(BrowserVersion.CHROME);
webClient.getOptions().setUseInsecureSSL(true); //ignore ssl certificate
webClient.getOptions().setThrowExceptionOnScriptError(false);
webClient.getOptions().setThrowExceptionOnFailingStatusCode(false);
String url = "https://www.wearvr.com/#game_id=game_4";
HtmlPage myPage = webClient.getPage(url);
webClient.waitForBackgroundJavaScriptStartingBefore(200);
webClient.waitForBackgroundJavaScript(20000);
//do stuff on page ex: myPage.getElementById("main")
//myPage.asXml() <- tags and elements
System.out.println(myPage.asText());
}
此外，你可以在这里看到更多关闭HtmlUnit警告
Also you can see more here Turning HtmlUnit Warnings off