NPE using RewritableTracer

[ehmke]

Hi,

I am getting an NPE trying to use the RewritableTracer. I just added some json copied from your examples. When I tried another snippet, it also NPEed but another part. Seems like target is null.

Thanks
Martin

Unexpected Exception java.lang.NullPointerException: null
	at io.opentracing.contrib.specialagent.LogFieldRewriter.log(LogFieldRewriter.java:76)
	at io.opentracing.contrib.specialagent.LogFieldRewriter.processLog(LogFieldRewriter.java:55)
	at io.opentracing.contrib.specialagent.RewritableSpan.log(RewritableSpan.java:71)
	at io.opentracing.contrib.specialagent.RewritableSpan.log(RewritableSpan.java:66)
	at io.opentracing.contrib.specialagent.LogFieldRewriter.log(LogFieldRewriter.java:76)
	at io.opentracing.contrib.specialagent.LogFieldRewriter.processLog(LogFieldRewriter.java:55)
	at io.opentracing.contrib.specialagent.RewritableSpan.log(RewritableSpan.java:71)
	at io.opentracing.contrib.specialagent.RewritableSpan.log(RewritableSpan.java:66)
	at io.opentracing.contrib.specialagent.rule.spring.webmvc.copied.HandlerInterceptorSpanDecorator$1.onPreHandle(HandlerInterceptorSpanDecorator.java:89)
	at io.opentracing.contrib.specialagent.rule.spring.webmvc.copied.TracingHandlerInterceptor.preHandle(TracingHandlerInterceptor.java:107)
	at org.springframework.web.servlet.HandlerExecutionChain.applyPreHandle(HandlerExecutionChain.java:137)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1035)
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)
...