Introduced by 2.0.0's off-heap feature, the interface RegionScanner extends a new interface Shipper which contains a "shipped()" method.
In our case, some application user defined customized scanner that implements Interface RegionScanner in 1.X .
After we back ported the Off Heap feature of 2.0.0, RegionScannerShippedCallBack throws a "java.lang.AbstractMethodError" when executing scanner.shipped(). It is because the customized scanner didn't override the shipped method yet.
Instead of forcing every user to add a empty implementation(if they don't really need to scan the file or the RS don't use L2 cache, they don't need to do anything in shipped method) , adding a default method of shipped in Interface RegionScanner might be a better way.