quota.addGetResult(r) throw NPE

Setting the RPC quota, table.exists(Get) cause quota.addGetResult(r)  throw  NPE.

set_quota TYPE => THROTTLE, NAMESPACE => 'ns1', LIMIT => '1000req/sec'

Connection conn = ConnectionFactory.createConnection(config);
Table htable = conn.getTable(TableName.valueOf("ns1:t1"));
boolean exists = htable.exists(new Get(Bytes.toBytes("123"))); 

log:

java.io.IOException: java.io.IOException
at org.apache.hadoop.hbase.ipc.RpcServer.call(RpcServer.java:2183)
at org.apache.hadoop.hbase.ipc.CallRunner.run(CallRunner.java:107)
at org.apache.hadoop.hbase.ipc.RpcExecutor.consumerLoop(RpcExecutor.java:133)
at org.apache.hadoop.hbase.ipc.RpcExecutor$1.run(RpcExecutor.java:108)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
at org.apache.hadoop.hbase.quotas.QuotaUtil.calculateResultSize(QuotaUtil.java:282)
at org.apache.hadoop.hbase.quotas.DefaultOperationQuota.addGetResult(DefaultOperationQuota.java:99)
at org.apache.hadoop.hbase.regionserver.RSRpcServices.get(RSRpcServices.java:1907)
at org.apache.hadoop.hbase.protobuf.generated.ClientProtos$ClientService$2.callBlockingMethod(ClientProtos.java:32381)
at org.apache.hadoop.hbase.ipc.RpcServer.call(RpcServer.java:2135)
... 4 more