В Java – как получить полную трассировку стека? ⇐ JAVA

[Anonymous]

В настоящее время при запуске кода я получаю следующий результат
Caused by: java.lang.NullPointerException
at com.gargoylesoftware.htmlunit.html.HtmlScript$2.execute(HtmlScript.java:227)
at com.gargoylesoftware.htmlunit.html.HtmlScript.onAllChildrenAddedToPage(HtmlScript.java:256)
at com.gargoylesoftware.htmlunit.html.parser.neko.HtmlUnitNekoDOMBuilder.endElement(HtmlUnitNekoDOMBuilder.java:560)
at org.apache.xerces.parsers.AbstractSAXParser.endElement(Unknown Source)
at com.gargoylesoftware.htmlunit.html.parser.neko.HtmlUnitNekoDOMBuilder.endElement(HtmlUnitNekoDOMBuilder.java:514)
at net.sourceforge.htmlunit.cyberneko.HTMLTagBalancer.callEndElement(HTMLTagBalancer.java:1192)
at net.sourceforge.htmlunit.cyberneko.HTMLTagBalancer.endElement(HTMLTagBalancer.java:1132)
at net.sourceforge.htmlunit.cyberneko.filters.DefaultFilter.endElement(DefaultFilter.java:219)
at net.sourceforge.htmlunit.cyberneko.filters.NamespaceBinder.endElement(NamespaceBinder.java:312)
at net.sourceforge.htmlunit.cyberneko.HTMLScanner$ContentScanner.scanEndElement(HTMLScanner.java:3189)
at net.sourceforge.htmlunit.cyberneko.HTMLScanner$ContentScanner.scan(HTMLScanner.java:2114)
at net.sourceforge.htmlunit.cyberneko.HTMLScanner.scanDocument(HTMLScanner.java:937)
at net.sourceforge.htmlunit.cyberneko.HTMLConfiguration.parse(HTMLConfiguration.java:443)
at net.sourceforge.htmlunit.cyberneko.HTMLConfiguration.parse(HTMLConfiguration.java:394)
at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
at com.gargoylesoftware.htmlunit.html.parser.neko.HtmlUnitNekoDOMBuilder.parse(HtmlUnitNekoDOMBuilder.java:760)
at com.gargoylesoftware.htmlunit.html.parser.neko.HtmlUnitNekoHtmlParser.parseFragment(HtmlUnitNekoHtmlParser.java:158)
at com.gargoylesoftware.htmlunit.html.parser.neko.HtmlUnitNekoHtmlParser.parseFragment(HtmlUnitNekoHtmlParser.java:112)
at com.gargoylesoftware.htmlunit.javascript.host.Element.parseHtmlSnippet(Element.java:868)
at com.gargoylesoftware.htmlunit.javascript.host.Element.setInnerHTML(Element.java:920)
at com.gargoylesoftware.htmlunit.javascript.host.html.HTMLElement.setInnerHTML(HTMLElement.java:676)
at sun.reflect.GeneratedMethodAccessor17.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at net.sourceforge.htmlunit.corejs.javascript.MemberBox.invoke(MemberBox.java:188)
... 30 more

Вышеупомянутое... еще 30 означает, что я не знаю строку моего кода, которая вызывает проблему. Как я могу получить полную трассировку стека?
Кроме того, если кажется, что он не выполняет ни один из моих операторов catch с помощью printStackTrace, но если я отключу ведение журнала с помощью команды ниже
java.util.logging.Logger.getLogger("com.gargoylesoftware.htmlunit").setLevel(java.util.logging.Level.OFF);

java.util.logging.Logger.getLogger("org.apache.http").setLevel(java.util.logging.Level.OFF);

**Have put in my full code below as suggested by the comments below . Did not put in the actual URL though**

import com.gargoylesoftware.htmlunit.html.*;
import java.io.File;
import com.gargoylesoftware.htmlunit.WebClient;
import com.gargoylesoftware.htmlunit.html.HtmlPage;

public class download_to_send_to_stackoverflow
{
public static void main(String args[])
{

String url = "did not want to include the actual web site ";

HtmlPage page = null;

WebClient webClient = new WebClient();
webClient.getOptions().setRedirectEnabled(true);
webClient.getOptions().setJavaScriptEnabled(true); // tried making false - but didnt work
webClient.getOptions().setCssEnabled(false);
webClient.getOptions().setUseInsecureSSL(true);
webClient.getOptions().setTimeout(30000);
webClient.setJavaScriptTimeout(30000); //e.g. 50s
webClient.waitForBackgroundJavaScript(15000) ; // added 2017/1/24
webClient.waitForBackgroundJavaScriptStartingBefore(30000) ; // added 2017/1/24

try
{
page = webClient.getPage( url );
savePage_just_html(page );
}

catch( Exception e )
{
System.out.println( "Exception thrown:----------------------------------------" + e.getMessage() );
e.printStackTrace();
}
}

protected static String savePage_just_html(HtmlPage page)
{
try
{
File saveFolder = new File("spool/_");
page.save(saveFolder); // this is the line causing the error with limit stack trace
}

catch ( Exception e )
{
System.out.println( "IOException was thrown: ---------------------------------- " + e.getMessage() );
e.printStackTrace();
}

return "file.html";
}

}

------------------------------------------------------

page.save(saveFolder); above is the problem line. if I take it out I dont get the limited statcktrace errors but I also dont save the html page - which I want to do

- The question is - why does this line only print a limited stacktrace


Подробнее здесь: https://stackoverflow.com/questions/634 ... tack-trace