java - 测试 java HBase 连接

Question

我正在尝试使用 HBase Java API 将数据写入 HBase。我通过 Ambari 安装了 Hadoop/HBase。

这是当前配置的设置方式:

final Configuration CONFIGURATION = HBaseConfiguration.create();
final HBaseAdmin HBASE_ADMIN;

HBASE_ADMIN = new HBaseAdmin(CONFIGURATION)

当我尝试写入 HBase 时，我会检查以确保该表存在

!HBASE_ADMIN.tableExists(tableName)

如果没有，创建一个新的。但是，似乎在尝试检查表是否存在时会抛出异常。

我想知道我是否没有正确连接到 HBase...有什么好的方法可以验证配置是否正确以及我是否正在连接到 HBase？我得到的异常如下。

谢谢。

---

java.lang.RuntimeException: java.lang.NullPointerException
  at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:209)
  at org.apache.hadoop.hbase.client.ClientScanner.call(ClientScanner.java:288)
  at org.apache.hadoop.hbase.client.ClientScanner.nextScanner(ClientScanner.java:268)
  at org.apache.hadoop.hbase.client.ClientScanner.initializeScannerInConstruction(ClientScanner.java:140)
  at org.apache.hadoop.hbase.client.ClientScanner.<init>(ClientScanner.java:135)
  at org.apache.hadoop.hbase.catalog.MetaReader.fullScan(MetaReader.java:597)
  at org.apache.hadoop.hbase.client.HTable.getScanner(HTable.java:802)
  at org.apache.hadoop.hbase.catalog.MetaReader.tableExists(MetaReader.java:359)
  at org.apache.hadoop.hbase.client.HBaseAdmin.tableExists(HBaseAdmin.java:287)
  at org.apache.hadoop.hbase.client.HBaseAdmin.tableExists(HBaseAdmin.java:301)
  at com.business.project.hbase.HBaseMessageWriter.getTable(HBaseMessageWriter.java:40)
  at com.business.project.hbase.HBaseMessageWriter.write(HBaseMessageWriter.java:59)
  at com.business.project.hbase.HBaseMessageWriter.write(HBaseMessageWriter.java:54)
  at com.business.project.storm.bolt.package.exampleBolt.execute(exampleBolt.java:19)
  at backtype.storm.daemon.executor$fn__5697$tuple_action_fn__5699.invoke(executor.clj:659)
  at backtype.storm.daemon.executor$mk_task_receiver$fn__5620.invoke(executor.clj:415)
  at backtype.storm.disruptor$clojure_handler$reify__1741.onEvent(disruptor.clj:58)
  at backtype.storm.utils.DisruptorQueue.consumeBatchToCursor(DisruptorQueue.java:125)
  at backtype.storm.utils.DisruptorQueue.consumeBatchWhenAvailable(DisruptorQueue.java:99)
  at backtype.storm.disruptor$consume_batch_when_available.invoke(disruptor.clj:80)
  at backtype.storm.daemon.executor$fn__5697$fn__5710$fn__5761.invoke(executor.clj:794)
  at backtype.storm.util$async_loop$fn__452.invoke(util.clj:465)
  at clojure.lang.AFn.run(AFn.java:24)
  at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
  at org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher.getMetaReplicaNodes(ZooKeeperWatcher.java:269)
  at org.apache.hadoop.hbase.zookeeper.MetaRegionTracker.blockUntilAvailable(MetaRegionTracker.java:241)
  at org.apache.hadoop.hbase.client.ZooKeeperRegistry.getMetaRegionLocation(ZooKeeperRegistry.java:62)
  at org.apache.hadoop.hbase.client.ConnectionManager$HConnectionImplementation.locateMeta(ConnectionManager.java:1203)
  at org.apache.hadoop.hbase.client.ConnectionManager$HConnectionImplementation.locateRegion(ConnectionManager.java:1164)
  at org.apache.hadoop.hbase.client.RpcRetryingCallerWithReadReplicas.getRegionLocations(RpcRetryingCallerWithReadReplicas.java:294)
  at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:130)
  at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:55)
  at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:201)

Answer 1

除了Yosr建议的配置参数外，指定

conf.set("zookeeper.znode.parent", "VALUE")

将有助于解决问题。