在 Spark 作业中使用流口水

Question

我正在尝试在提交给集群的 spark 作业中使用 drools。这项工作将首先从 drools 服务器获取 drools jar，然后初始化基础和会话。我的代码在 Spark 中执行时可以工作，但是在提交到 Spark 集群时会发生 NPE。这就是我的做法String url = "{my server address}/drools-wb/maven2/com/myspace/Project1/1.0.0/Project1-1.0.0.jar";KieServices ks = KieServices.Factory.get();//ERROR is in the below line ReleaseId releaseId = ks.newReleaseId("com.myspace", "Project1", "1.0.0"); KieRepository kr = ks.getRepository();UrlResource urlResource = (UrlResource) ks.getResources().newUrlResource(url);提交代码后报错：Exception in thread "main" java.lang.NullPointerException    at org.opencell.spark.jobs.TestWithDrools.main(TestWithDrools.java:47)    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)    at java.lang.reflect.Method.invoke(Method.java:498)    at org.apache.spark.deploy.JavaMainApplication.start(SparkApplication.scala:52)    at org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:879)    at org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:197)    at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:227)    at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:136)    at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)2018-08-29 10:08:09 INFO  ShutdownHookManager:54 - Shutdown hook called你有解决这个问题的想法吗？

Answer 1

该问题是由于 ks 为空引起的。