public void completeAndWait(WriteEntry e) {
    if (!complete(e)) {
      waitForRead(e);
    }
  }
Complete a {@link WriteEntry} that was created by {@link #begin()} then wait until the read
point catches up to our write. At the end of this call, the global read point is at least as
large as the write point of the passed in WriteEntry. Thus, the write is visible to MVCC
readers.
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/MultiVersionConcurrencyControl.java