异常
预取hbase时遇到问题：元表:: org.apache.hadoop.hbase.client.RetriesExhaustedException：尝试次数= 10后失败，异常：
Mon Nov 03 13:08:31 2014，org.apache.hadoop.hbase.client.RpcRetryingCaller @ 3ffd47ab，java.io.IOException：com.google.protobuf.ServiceException：java.lang.NullPointerException Mon Nov 03 13:08:31 2014，org.apache.hadoop.hbase.client.RpcRetryingCaller @ 3ffd47ab，java.io.IOException：com.google.protobuf.ServiceException：java.lang.NullPointerException Mon Nov 03 13:08:32 EST 2014，org.apache.hadoop.hbase.client.RpcRetryingCaller @ 3ffd47ab，java.io.IOException：com.google.protobuf.ServiceException：java.lang.NullPointerException Mon Nov 03 13:08:33 2014，org.apache.hadoop.hbase.client.RpcRetryingCaller @ 3ffd47ab，java.io.IOException：com.google.protobuf.ServiceException：java.lang.NullPointerException Mon Nov 03 13:08:35 2014，org.apache.hadoop.hbase.client.RpcRetryingCaller @ 3ffd47ab，java.io.IOException：com.google.protobuf.ServiceException：java.lang.NullPointerException Mon Nov 03 13:08:39 2014，org.apache.hadoop.hbase.client.RpcRetryingCaller @ 3ffd47ab，java.io.IOException：com.google.protobuf.ServiceException：java.lang.NullPointerException Mon Nov 03 13:08:49 2014，org.apache.hadoop.hbase.client.RpcRetryingCaller @ 3ffd47ab，java.io.IOException：com.google.protobuf.ServiceException：java.lang.NullPointerException Mon Nov 03 13:08:59 2014，org.apache.hadoop.hbase.client.RpcRetryingCaller @ 3ffd47ab，java.io.IOException：com.google.protobuf.ServiceException：java.lang.NullPointerException Mon Nov 03 13:09:09 2014，org.apache.hadoop.hbase.client.RpcRetryingCaller @ 3ffd47ab，java.io.IOException：com.google.protobuf.ServiceException：java.lang.NullPointerException Mon Nov 03 13:09:19 2014，org.apache.hadoop.hbase.client.RpcRetryingCaller @ 3ffd47ab，java.io.IOException：com.google.protobuf.ServiceException：java.lang.NullPointerException Mon Nov 03 13:07:43 2014，org.apache.hadoop.hbase.client.RpcRetryingCaller@15465e3b，java.io.IOException：com.google.protobuf.ServiceException：java.lang.NullPointerException 在org.apache.hadoop.hbase.client.RpcRetryingCaller.callWithRetries（RpcRetryingCaller.java:129）[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] 在org.apache.hadoop.hbase.client.HTable.getRowOrBefore（HTable.java:710）[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] 在org.apache.hadoop.hbase.client.MetaScanner.metaScan（MetaScanner.java:144）[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] 在org.apache.hadoop.hbase.client.HConnectionManager $ HConnectionImplementation.prefetchRegionCache（HConnectionManager.java:1158）[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] at org.apache.hadoop.hbase.client.HConnectionManager $ HConnectionImplementation.locateRegionInMeta（HConnectionManager.java:1222)[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] at org.apache.hadoop.hbase.client.HConnectionManager $ HConnectionImplementation.locateRegion（HConnectionManager.java:1110)[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] at org.apache.hadoop.hbase.client.HConnectionManager $ HConnectionImplementation.locateRegion（HConnectionManager.java:1067)[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] 在org.apache.hadoop.hbase.client.AsyncProcess.findDestLocation（AsyncProcess.java:356）[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] at org.apache.hadoop.hbase.client.AsyncProcess.submit（AsyncProcess.java:301）[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] 在org.apache.hadoop.hbase.client.HTable.backgroundFlushCommits（HTable.java:955）[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] 在org.apache.hadoop.hbase.client.HTable.flushCommits(HTable.java:1239）[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] 在org.apache.hadoop.hbase.client.HTable.put（HTable.java:901）[hbase-client-0.98.1-hadoop2.jar：0.98.1-hadoop2] at org.datanucleus.store.hbase.HBasePersistenceHandler.insertObject（HBasePersistenceHandler.java:284）[datanucleus-hbase-3.1.1.jar：] at org.datanucleus.state.JDOStateManager.internalMakePersistent（JDOStateManager.java:2377） at org.datanucleus.state.JDOStateManager.makePersistent（JDOStateManager.java:2353） at org.datanucleus.ObjectManagerImpl.persistObjectInternal（ObjectManagerImpl.java:1896)[datanucleus-core-3.1.2.jar:[ at org.datanucleus.ObjectManagerImpl.persistObjectWork（ObjectManagerImpl.java:1745）[datanucleus-core-3.1.2.jar：] at org.datanucleus.ObjectManagerImpl.persistObject（ObjectManagerImpl.java:1602）[datanucleus-core-3.1.2.jar：] 在org.datanucleus.api.jdo.JDOPersistenceManager.jdoMakePersistent（JDOPersistenceManager.java:731）[datanucleus-api-jdo-3.1.2.jar：] 在org.datanucleus.api.jdo.JDOPersistenceManager.makePersistent（JDOPersistenceManager.java:756）[datanucleus-api-jdo-3.1.2.jar：]