[HBASE-16732] Avoid possible NPE in MetaTableLocator

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 1.3.0, 1.2.4, 2.0.0
• Assignee: Jerry He
• Reporter: Jerry He
• Created: 29/Sep/16 17:06
• Updated: 09/Nov/17 01:38
• Resolved: 29/Sep/16 21:20

Description

java.lang.NullPointerException: null
        at org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher.getMetaReplicaNodes(ZooKeeperWatcher.java:489)
        at org.apache.hadoop.hbase.zookeeper.MetaTableLocator.blockUntilAvailable(MetaTableLocator.java:549)
        at org.apache.hadoop.hbase.client.ZooKeeperRegistry.getMetaRegionLocation(ZooKeeperRegistry.java:61)
        at org.apache.hadoop.hbase.client.ConnectionManager$HConnectionImplementation.locateMeta(ConnectionManager.java:1211)
        at org.apache.hadoop.hbase.client.ConnectionManager$HConnectionImplementation.locateRegion(ConnectionManager.java:1178)
        at org.apache.hadoop.hbase.client.RpcRetryingCallerWithReadReplicas.getRegionLocations(RpcRetryingCallerWithReadReplicas.java:305)
        at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:156)
        at org.apache.hadoop.hbase.client.ScannerCallableWithReplicas.call(ScannerCallableWithReplicas.java:60)
        at org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithoutRetries(RpcRetryingCaller.java:200)
        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.<init>(ClientScanner.java:155)
        at org.apache.hadoop.hbase.client.HTable.getScanner(HTable.java:804)
        at org.apache.hadoop.hbase.MetaTableAccessor.fullScan(MetaTableAccessor.java:602)
        at org.apache.hadoop.hbase.MetaTableAccessor.tableExists(MetaTableAccessor.java:366)
        at org.apache.hadoop.hbase.client.HBaseAdmin.tableExists(HBaseAdmin.java:396)
        at com.thinkaurelius.titan.diskstorage.hbase.HBaseAdmin1_2.clearTable(HBaseAdmin1_2.java:38)
        at com.thinkaurelius.titan.diskstorage.hbase.HBaseStoreManager.clearStorage(HBaseStoreManager.java:483)

It happens when hbase is not fully up, and the client comes in.