@Override
  public void start(CoprocessorEnvironment env) throws IOException {
    if (env instanceof RegionCoprocessorEnvironment) {
      this.env = (RegionCoprocessorEnvironment) env;
    } else {
      throw new CoprocessorException("Must be loaded on a table region!");
    }
  }
Coprocessor endpoint to refresh HFiles on replica.
<p>
<p>
For the protocol buffer definition of the RefreshHFilesService, see the source file located under
hbase-protocol/src/main/protobuf/RefreshHFiles.proto.
</p>
hbase-examples/src/main/java/org/apache/hadoop/hbase/coprocessor/example/RefreshHFilesEndpoint.java