Umesh Agashe created HBASE-20135: ------------------------------------ Summary: NullPointerException during reading bloom filter when upgraded from hbase-1 to hbase-2 Key: HBASE-20135 URL: https://issues.apache.org/jira/browse/HBASE-20135 Project: HBase Issue Type: Improvement Affects Versions: 2.0.0-beta-2 Reporter: Umesh Agashe Fix For: 2.0.0
When upgraded from hbase-1 to hbase-2, found following exception logged multiple times in the log: {code:java} ERROR [StoreFileOpenerThread-test_cf-1] regionserver.StoreFileReader: Error reading bloom filter meta for GENERAL_BLOOM_META -- proceeding without java.io.IOException: Comparator class org.apache.hadoop.hbase.KeyValue$RawBytesComparator is not instantiable at org.apache.hadoop.hbase.io.hfile.FixedFileTrailer.createComparator(FixedFileTrailer.java:628) at org.apache.hadoop.hbase.io.hfile.CompoundBloomFilter.<init>(CompoundBloomFilter.java:79) at org.apache.hadoop.hbase.util.BloomFilterFactory.createFromMeta(BloomFilterFactory.java:104) at org.apache.hadoop.hbase.regionserver.StoreFileReader.loadBloomfilter(StoreFileReader.java:479) at org.apache.hadoop.hbase.regionserver.HStoreFile.open(HStoreFile.java:425) at org.apache.hadoop.hbase.regionserver.HStoreFile.initReader(HStoreFile.java:460) at org.apache.hadoop.hbase.regionserver.HStore.createStoreFileAndReader(HStore.java:671) at org.apache.hadoop.hbase.regionserver.HStore.lambda$openStoreFiles$0(HStore.java:537) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) at java.util.concurrent.FutureTask.run(FutureTask.java:266) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at java.lang.Thread.run(Thread.java:748) Caused by: java.lang.NullPointerException{code} Analysis from [~anoop.hbase]: Checking the related code. There seems no issue.. We are not going to even fail reading the bloom. In 2.0 code base we expect the comparator class name to be null. But in 1.x we write old KV based Raw Bytes comparator class name. So reading that back, we will return class name as null and we get NPE it looks like. else if (comparatorClassName.equals("org.apache.hadoop.hbase.KeyValue$RawBytesComparator") || comparatorClassName.equals("org.apache.hadoop.hbase.util.Bytes$ByteArrayComparator")) { // When the comparator to be used is Bytes.BYTES_RAWCOMPARATOR, we just return null from here // Bytes.BYTES_RAWCOMPARATOR is not a CellComparator comparatorKlass = null; } We can better do a null check before trying the comparator class instantiation so that we can avoid this scary error logs :-) -- This message was sent by Atlassian JIRA (v7.6.3#76005)