Can not send email caused by Build Base Cuboid Data step failed

I build a cube but it failed in the "Build Base Cuboid Data" step, I can not get job failed email and find the stacktrace in log :
java.lang.NullPointerException
at java.util.regex.Matcher.appendReplacement(Matcher.java:758)
at java.util.regex.Matcher.replaceAll(Matcher.java:906)
at java.lang.String.replaceAll(String.java:2162)
at org.apache.kylin.job.cube.CubingJob.formatNotifications(CubingJob.java:98)
at org.apache.kylin.job.execution.AbstractExecutable.notifyUserStatusChange(AbstractExecutable.java:211)
at org.apache.kylin.job.execution.DefaultChainedExecutable.onExecuteFinished(DefaultChainedExecutable.java:101)
at org.apache.kylin.job.cube.CubingJob.onExecuteFinished(CubingJob.java:130)
at org.apache.kylin.job.execution.AbstractExecutable.execute(AbstractExecutable.java:113)
at org.apache.kylin.job.impl.threadpool.DefaultScheduler$JobRunner.run(DefaultScheduler.java:130)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)

This is caused by CubingJob.getSourceRecordCount() function return null while get this job input source recode, So here need a recheck before return .