java - Handled exception still being written to stdout -

i'm using jetty server hosting java app. added request timeouts kill requests take long. file logs stdout (which should empty) started fill interruptedexception stack traces. like:

java.lang.interruptedexception     ...... lower level code-lines of project     @ com.mycompany.webapps.mycontroller.mymethod(mycontroller.java:252)     @ sun.reflect.generatedmethodaccessor67.invoke(unknown source)     @ sun.reflect.delegatingmethodaccessorimpl.invoke(delegatingmethodaccessorimpl.java:43)     @ java.lang.reflect.method.invoke(method.java:601)     @ org.springframework.web.method.support.invocablehandlermethod.invoke(invocablehandlermethod.java:219)     @ org.springframework.web.method.support.invocablehandlermethod.invokeforrequest(invocablehandlermethod.java:132)     @ org.springframework.web.servlet.mvc.method.annotation.servletinvocablehandlermethod.invokeandhandle(servletinvocablehandlermethod.java:104)     @ org.springframework.web.servlet.mvc.method.annotation.requestmappinghandleradapter.invokehandlemethod(requestmappinghandleradapter.java:745)     @ org.springframework.web.servlet.mvc.method.annotation.requestmappinghandleradapter.handleinternal(requestmappinghandleradapter.java:686)     @ org.springframework.web.servlet.mvc.method.abstracthandlermethodadapter.handle(abstracthandlermethodadapter.java:80)     @ org.springframework.web.servlet.dispatcherservlet.dodispatch(dispatcherservlet.java:925)     @ org.springframework.web.servlet.dispatcherservlet.doservice(dispatcherservlet.java:856)     @ org.springframework.web.servlet.frameworkservlet.processrequest(frameworkservlet.java:920)     @ org.springframework.web.servlet.frameworkservlet.doget(frameworkservlet.java:816)     @ javax.servlet.http.httpservlet.service(httpservlet.java:687)     @ org.springframework.web.servlet.frameworkservlet.service(frameworkservlet.java:801)     @ javax.servlet.http.httpservlet.service(httpservlet.java:790)     @ org.eclipse.jetty.servlet.servletholder.handle(servletholder.java:738)     @ org.eclipse.jetty.servlet.servlethandler$cachedchain.dofilter(servlethandler.java:1651)     @ org.eclipse.jetty.servlets.useragentfilter.dofilter(useragentfilter.java:83)     @ org.eclipse.jetty.servlets.gzipfilter.dofilter(gzipfilter.java:310)     @ org.eclipse.jetty.servlet.servlethandler$cachedchain.dofilter(servlethandler.java:1622)     @ org.eclipse.jetty.servlet.servlethandler.dohandle(servlethandler.java:549)     @ org.eclipse.jetty.server.handler.scopedhandler.handle(scopedhandler.java:143)     @ org.eclipse.jetty.security.securityhandler.handle(securityhandler.java:568)     @ org.eclipse.jetty.server.session.sessionhandler.dohandle(sessionhandler.java:221)     @ org.eclipse.jetty.server.handler.contexthandler.dohandle(contexthandler.java:1111)     @ org.eclipse.jetty.servlet.servlethandler.doscope(servlethandler.java:478)     @ org.eclipse.jetty.server.session.sessionhandler.doscope(sessionhandler.java:183)     @ org.eclipse.jetty.server.handler.contexthandler.doscope(contexthandler.java:1045)     @ org.eclipse.jetty.server.handler.scopedhandler.handle(scopedhandler.java:141)     @ org.eclipse.jetty.server.handler.contexthandlercollection.handle(contexthandlercollection.java:199)     @ org.eclipse.jetty.server.handler.handlercollection.handle(handlercollection.java:109)     @ org.eclipse.jetty.server.handler.handlerwrapper.handle(handlerwrapper.java:97)     @ org.eclipse.jetty.server.handler.statisticshandler.handle(statisticshandler.java:159)     @ org.eclipse.jetty.server.handler.handlerwrapper.handle(handlerwrapper.java:97)     @ org.eclipse.jetty.server.server.handle(server.java:462)     @ org.eclipse.jetty.server.httpchannel.handle(httpchannel.java:279)     @ org.eclipse.jetty.server.httpconnection.onfillable(httpconnection.java:232)     @ org.eclipse.jetty.io.abstractconnection$2.run(abstractconnection.java:534)     @ org.eclipse.jetty.util.thread.queuedthreadpool.runjob(queuedthreadpool.java:607)     @ org.eclipse.jetty.util.thread.queuedthreadpool$3.run(queuedthreadpool.java:536) 

so, added try-catch in mymethod (the highest method under control):

@requestmapping(value = "/myurl/{id}", method = requestmethod.get) @responsebody public responseentity<byte[]> mymethod(final httpservletrequest request, @pathvariable final encodedid id) {   try {     return serveimagerequest(request, sourceid.getid(), docid.getid(), dimensions.getwidth(), dimensions.getheight());   } catch (exception ex) {     log.error(ex.getmessage());     return null;   } } 

the log variable logger instance (using log4j) writes messages dedicated log file (and not stdout). , still, messages written stdout. difference they're written log file. can't find reason written stdout , have avoid since file represents stdout not have rolling policy.

turns out root issue in 3rd party library catches exception , prints stack trace stdout. this being printed although caught , handled exception.