[HBASE-3793] HBASE-3468 Broke checkAndPut with null value

• Type: Bug
• Status: Closed
• Priority: Blocker
• Resolution: Fixed
• Affects Version/s: 0.92.0
• Fix Version/s: 0.92.0
• Component/s: regionserver
• Hadoop Flags: Reviewed
• Assignee: Ming Ma
• Reporter: Lars George
• Created: 16/Apr/11 17:42
• Updated: 20/Nov/15 12:41
• Resolved: 13/Jun/11 23:44

Description

The previous code called Bytes.equal() which does a check for "null" on the left or right argument. Now the comparator calls Bytes.compareTo() - which has no check for null. But this is a valid input and checks for existence. I actually noticed this running

https://github.com/larsgeorge/hbase-book/blob/master/ch04/src/main/java/client/CheckAndPutExample.java

This used to work, now it throws an NPE

Caused by: java.lang.NullPointerException
	at org.apache.hadoop.hbase.util.Bytes.compareTo(Bytes.java:854)
	at org.apache.hadoop.hbase.filter.WritableByteArrayComparable.compareTo(WritableByteArrayComparable.java:63)
	at org.apache.hadoop.hbase.regionserver.HRegion.checkAndMutate(HRegion.java:1681)
	at org.apache.hadoop.hbase.regionserver.HRegionServer.checkAndMutate(HRegionServer.java:1693)
	... 6 more


	at org.apache.hadoop.hbase.client.HConnectionManager$HConnectionImplementation.getRegionServerWithRetries(HConnectionManager.java:1026)
	at org.apache.hadoop.hbase.client.HTable.checkAndPut(HTable.java:750)
	at client.CheckAndPutExample.main(CheckAndPutExample.java:33)

Easy fixable, just needs to handle the null value before even calling comparator.compareTo().