Axis Server.userException NullPointerException

Exception in thread "main" AxisFault
faultCode: {http://schemas.xmlsoap.org/soap/envelope/}Server.userException
faultSubcode:
faultString: java.lang.NullPointerException
faultActor:
faultNode:
faultDetail:

java.lang.NullPointerException
at org.apache.axis.message.SOAPFaultBuilder.createFault(SOAPFaultBuilder
.java:260)
at org.apache.axis.message.SOAPFaultBuilder.endElement(SOAPFaultBuilder.
java:169)
at org.apache.axis.encoding.DeserializationContextImpl.endElement(Deseri
alizationContextImpl.java:1015)
at org.apache.xerces.parsers.AbstractSAXParser.endElement(Unknown Source
)
at org.apache.xerces.impl.XMLNSDocumentScannerImpl.scanEndElement(Unknow
n Source)
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl$FragmentContent
Dispatcher.dispatch(Unknown Source)
at org.apache.xerces.impl.XMLDocumentFragmentScannerImpl.scanDocument(Un
known Source)
at org.apache.xerces.parsers.XML11Configuration.parse(Unknown Source)
at org.apache.xerces.parsers.DTDConfiguration.parse(Unknown Source)
at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
at javax.xml.parsers.SAXParser.parse(Unknown Source)
at org.apache.axis.encoding.DeserializationContextImpl.parse(Deserializa
tionContextImpl.java:242)
at org.apache.axis.SOAPPart.getAsSOAPEnvelope(SOAPPart.java:538)
at org.apache.axis.Message.getSOAPEnvelope(Message.java:376)
at org.apache.axis.client.Call.invokeEngine(Call.java:2583)
at org.apache.axis.client.Call.invoke(Call.java:2553)
at org.apache.axis.client.Call.invoke(Call.java:2248)
at org.apache.axis.client.Call.invoke(Call.java:2171)
at org.apache.axis.client.Call.invoke(Call.java:1691)


Googled. Thousands of matched pages returned. Checked the previous pages, nothing helpful.

Finally, through debugging server side codes, found the root cause, it's just common Exception. Just because used third party framework or tools, it hides the low level exceptions, it makes debug painful :(

Google can really help in work, but it's not enough. It returned too many results and not accurate. It wasted a lot of time.

Where can I found such a search engine, it purely collect all kinds of problems and it's accurate solutions?

I think the knowledge search engine should have three features:
1) Understand questions.
    One question have many kinds of expressions. Different people have different expression method, the search engine should understand what people really wanna ask.

2) It should return as few results as possible.
   Too many results will drown people. It will waste too much time to find the useful answer.

3) It should accurate.
    The results should answer the questions, not just match the words of questions. It should be tested by many of users. That is, it have been proved to be real solution.

4) It should be dynamic.
    The results should be ordered in some extends by human beings. People find the useful answer will have an easy way to mark it. Then the result will have bigger weight in searched result order.