similar issues here:
_Recording test results
[ZapiTestResultReporter] [INFO] Examining test results...
Build result is SUCCESS
Total Test Cases : 1ERROR: Build step failed with exception
java.lang.NullPointerException
at java.lang.String.replace(String.java:2180)
at com.thed.zephyr.jenkins.utils.rest.TestCaseUtil.fetchExecutionIdsZFJC(TestCaseUtil.java:884)
at com.thed.zephyr.jenkins.utils.rest.TestCaseUtil.processTestCaseDetails(TestCaseUtil.java:571)
at com.thed.zephyr.jenkins.reporter.ZfjReporter.perform(ZfjReporter.java:99)
at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:20)
at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:779)
at hudson.model.AbstractBuild$AbstractBuildExecution.performAllBuildSteps(AbstractBuild.java:720)
at hudson.model.Build$BuildExecution.post2(Build.java:186)
at hudson.model.AbstractBuild$AbstractBuildExecution.post(AbstractBuild.java:665)
at hudson.model.Run.execute(Run.java:1753)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43)
at hudson.model.ResourceController.execute(ResourceController.java:98)
at hudson.model.Executor.run(Executor.java:405)
Build step 'Publish test result to Zephyr for JIRA' marked build as failure
Finished: FAILURE_

Hi guys, are there any updates on this? What might be the issue?

According to the Zephyr support it is related to the Junit XML, which HAS to be genereted by surfire. I don't use Surfire, so couldn't validate if it is working with that.
Here is their response:
_ZAPI is needed for the same and you need to be logged into it and Jira for the same

Another preconditions are that
1. You should be selecting Maven project while using this plugin and the report generated should be 'sure-fire' report which is required by the plugin. We have seen similar issues with customers when the output is not of maven surefire reports
2.Also please check if your Jira has mandatory Fields.We support for now only "Summary" as Mandatory field

Also note that as the plugin is open source to get your integration working, I would recommend looking at the source code and then modifying the parser that suits your needs. You can find the source code in the link below:
https://github.com/jenkinsci/zephyr-for-jira-test-management-plugin

I checked out the source code and debugged 1.4 version plugin and found it's due to the mandatory customized filed of our testcases. I've modified the code and fixed the issue. 

Sorry, I don't understand. All the fields are populated:

JIRA URL, Project Name, Version, Cycle, Cycle Duration, Cycle Prefix.

Why is NullPointer appearing then? 

Same problem here, is there a solution?

Our Environment:

• Jenkins ver. 2.60.1
  • Zephyr for JIRA Test Management plugin 1.4
• JIRA v7.3.8
  • Zephyr for JIRA 3.6.1
  • ZAPI for JIRA 2.5.0

We get this NPE only, if we used the option "New Cycle" or if we select an empty cycle.
So, at the first try, the cycle with all tests will be created, but without the results, if we retry in the same cycle the results will be pushed correctly to JIRA. The same, if we create an empty cycle (directly in JIRA), all tests without any results will be created (first try), the second pushed then the results.

Is there already any solution or workaround? Thanks for helping.

Here is our stack trace:

Recording test results
Archiving artifacts
[ZapiTestResultReporter] [INFO] Examining test results...
Build result is SUCCESS
Total Test Cases : 3ERROR: Build step failed with exception
java.lang.NullPointerException
at com.thed.zephyr.jenkins.utils.rest.TestCaseUtil.executeTests(TestCaseUtil.java:424)
at com.thed.zephyr.jenkins.utils.rest.TestCaseUtil.processTestCaseDetails(TestCaseUtil.java:564)
at com.thed.zephyr.jenkins.reporter.ZfjReporter.perform(ZfjReporter.java:99)
at hudson.tasks.BuildStepMonitor$1.perform(BuildStepMonitor.java:20)
at hudson.model.AbstractBuild$AbstractBuildExecution.perform(AbstractBuild.java:735)
at hudson.model.AbstractBuild$AbstractBuildExecution.performAllBuildSteps(AbstractBuild.java:676)
at hudson.model.Build$BuildExecution.post2(Build.java:186)
at hudson.model.AbstractBuild$AbstractBuildExecution.post(AbstractBuild.java:621)
at hudson.model.Run.execute(Run.java:1760)
at hudson.model.FreeStyleBuild.run(FreeStyleBuild.java:43)
at hudson.model.ResourceController.execute(ResourceController.java:97)
at hudson.model.Executor.run(Executor.java:405)
Build step 'Publish test result to Zephyr for JIRA' marked build as failure
Finished: FAILURE
 

Null pointer exception occurs if their is no bug in JIRA with the name equivalent to your script's package name.

For example if your package name is com.hello and your function name is test1() in the script, then there should be a bug in JIRA with the name com.hello.test1.

And the issue type as "Test".

Now when u run the build from jenkins, after execution it will search for the name com.hello.test1 and publish the result(pass/fail) to it.

This works especially for TestNG scripts.