@Override
    public WAL.Entry filter(WAL.Entry entry) {
      if (countFailures == numFailures) {
        return entry;
      }
      countFailures = countFailures + 1;
      throw new WALEntryFilterRetryableException("failing filter");
    }
Tests that if we stop before hitting the end of a stream, we can continue where we left off
using the last position
hbase-server/src/test/java/org/apache/hadoop/hbase/replication/regionserver/TestBasicWALEntryStream.java