title: NullPointerException emergs when I try to extract data from a hbase table using newAPIHadoopRDD
body: <pre><code>Exception in thread "main" java.lang.RuntimeException: java.lang.NullPointerException
      at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:208)
      at org.apache.hadoop.hbase.client.ClientScanner.call(ClientScanner.java:320)
      at org.apache.hadoop.hbase.client.ClientScanner.nextScanner(ClientScanner.java:295)
      at org.apache.hadoop.hbase.client.ClientScanner.initializeScannerInConstruction(ClientScanner.java:160)
      at org.apache.hadoop.hbase.client.ClientScanner.&lt;init&gt;(ClientScanner.java:155)
      at org.apache.hadoop.hbase.client.HTable.getScanner(HTable.java:821)
      at org.apache.hadoop.hbase.client.MetaScanner.metaScan(MetaScanner.java:193)
      at org.apache.hadoop.hbase.client.MetaScanner.metaScan(MetaScanner.java:89)
      at org.apache.hadoop.hbase.client.MetaScanner.allTableRegions(MetaScanner.java:324)
      at org.apache.hadoop.hbase.client.HRegionLocator.getAllRegionLocations(HRegionLocator.java:88)
      at org.apache.hadoop.hbase.util.RegionSizeCalculator.init(RegionSizeCalculator.java:94)
      at org.apache.hadoop.hbase.util.RegionSizeCalculator.&lt;init&gt;(RegionSizeCalculator.java:81)
      at org.apache.hadoop.hbase.mapreduce.TableInputFormatBase.getSplits(TableInputFormatBase.java:256)
      at org.apache.hadoop.hbase.mapreduce.TableInputFormat.getSplits(TableInputFormat.java:237)
      at org.apache.spark.rdd.NewHadoopRDD.getPartitions(NewHadoopRDD.scala:120)
      at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:242)
      at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:240)
      at scala.Option.getOrElse(Option.scala:120)
      at org.apache.spark.rdd.RDD.partitions(RDD.scala:240)
      at org.apache.spark.rdd.MapPartitionsRDD.getPartitions(MapPartitionsRDD.scala:35)
      at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:242)
      at org.apache.spark.rdd.RDD$$anonfun$partitions$2.apply(RDD.scala:240)
      at scala.Option.getOrElse(Option.scala:120)
      at org.apache.spark.rdd.RDD.partitions(RDD.scala:240)
      at org.apache.spark.SparkContext.runJob(SparkContext.scala:1953)
      at org.apache.spark.rdd.RDD$$anonfun$collect$1.apply(RDD.scala:934)
      at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:150)
      at org.apache.spark.rdd.RDDOperationScope$.withScope(RDDOperationScope.scala:111)
      at org.apache.spark.rdd.RDD.withScope(RDD.scala:323)
      at org.apache.spark.rdd.RDD.collect(RDD.scala:933)
      at com.dnvgl.eta.HbaseToCsv$.main(HbaseToCsv.scala:69)
      at com.dnvgl.eta.HbaseToCsv.main(HbaseToCsv.scala)
      at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
      at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
      at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
      at java.lang.reflect.Method.invoke(Method.java:498)
      at org.apache.spark.deploy.SparkSubmit$.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:738)
      at org.apache.spark.deploy.SparkSubmit$.doRunMain$1(SparkSubmit.scala:181)
      at org.apache.spark.deploy.SparkSubmit$.submit(SparkSubmit.scala:206)
      at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:121)
      at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
  Caused by: java.lang.NullPointerException
      at org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher.getMetaReplicaNodes(ZooKeeperWatcher.java:395)
      at org.apache.hadoop.hbase.zookeeper.MetaTableLocator.blockUntilAvailable(MetaTableLocator.java:553)
      at org.apache.hadoop.hbase.client.ZooKeeperRegistry.getMetaRegionLocation(ZooKeeperRegistry.java:61)
      at org.apache.hadoop.hbase.client.ConnectionManager$HConnectionImplementation.locateMeta(ConnectionManager.java:1186)
      at org.apache.hadoop.hbase.client.ConnectionManager$HConnectionImplementation.locateRegion(ConnectionManager.java:1153)
      at org.apache.hadoop.hbase.client.RpcRetryingCallerWithReadReplicas.getRegionLocations(RpcRetryingCallerWithReadReplicas.java:300)
      at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:155)
      at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:59)
      at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:200)
      ... 40 more
  </code></pre>
  
  <p>can any one give some advices? thank you very much.</p>