void checkInterrupt() throws NotServingRegionException, InterruptedIOException {
    if (Thread.interrupted()) {
      if (this.closing.get()) {
        throw new NotServingRegionException(
          getRegionInfo().getRegionNameAsString() + " is closing");
      }
      throw new InterruptedIOException();
    }
  }
Check thread interrupt status and throw an exception if interrupted.
@throws NotServingRegionException if region is closing
@throws InterruptedIOException    if interrupted but region is not closing
hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegion.java