# I am getting Null pointer exception by invoking web service task there is no stacktrace available

**URL:** <https://forum.flowable.org/t/i-am-getting-null-pointer-exception-by-invoking-web-service-task-there-is-no-stacktrace-available/1641>\
**Category:** Uncategorized\
**Created:** [February 14, 2018, 11:03am UTC](https://forum.flowable.org/t/i-am-getting-null-pointer-exception-by-invoking-web-service-task-there-is-no-stacktrace-available/1641 "2018-02-14T11:03:12Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![musaid](https://avatars.discourse-cdn.com/v4/letter/m/85e7bf/32.png) [@musaid](https://forum.flowable.org/u/musaid)\
**Post date:** [February 14, 2018, 11:03am UTC](https://forum.flowable.org/t/i-am-getting-null-pointer-exception-by-invoking-web-service-task-there-is-no-stacktrace-available/1641/1 "2018-02-14T11:03:12Z")

</div>

When i start process byKey

ProcessInstance processInstance = runtimeService.startProcessInstanceByKey(“weather” , variables);

Exception occur

jjava.lang.NullPointerException: null  
at org.flowable.engine.impl.bpmn.webservice.Operation.sendMessage(Operation.java:54)  
at org.flowable.engine.impl.bpmn.behavior.WebServiceActivityBehavior.execute(WebServiceActivityBehavior.java:136)  
at org.flowable.engine.impl.agenda.ContinueProcessOperation.executeActivityBehavior(ContinueProcessOperation.java:256)  
at org.flowable.engine.impl.agenda.ContinueProcessOperation.executeSynchronous(ContinueProcessOperation.java:154)  
at org.flowable.engine.impl.agenda.ContinueProcessOperation.continueThroughFlowNode(ContinueProcessOperation.java:111)  
at org.flowable.engine.impl.agenda.ContinueProcessOperation.continueThroughSequenceFlow(ContinueProcessOperation.java:303)  
at org.flowable.engine.impl.agenda.ContinueProcessOperation.run(ContinueProcessOperation.java:77)  
at org.flowable.engine.impl.interceptor.CommandInvoker.executeOperation(CommandInvoker.java:88)  
at org.flowable.engine.impl.interceptor.CommandInvoker.executeOperations(CommandInvoker.java:72)  
at org.flowable.engine.impl.interceptor.CommandInvoker.execute(CommandInvoker.java:56)  
at org.flowable.engine.impl.interceptor.BpmnOverrideContextInterceptor.execute(BpmnOverrideContextInterceptor.java:25)  
at org.flowable.engine.common.impl.interceptor.TransactionContextInterceptor.execute(TransactionContextInterceptor.java:53)  
at org.flowable.engine.common.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:72)  
at org.flowable.engine.common.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:35)  
at org.flowable.engine.common.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:56)  
at org.flowable.engine.common.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:51)  
at org.flowable.engine.impl.RuntimeServiceImpl.startProcessInstanceByKey(RuntimeServiceImpl.java:103)