code: @Override
      public void acceptMastership(int partitionId) {
          synchronized(m_dataSourcesByPartition) {
              Map<String, ExportDataSource> partitionDataSourceMap = m_dataSourcesByPartition.get(partitionId);
  
              // this case happens when there are no export tables
              if (partitionDataSourceMap == null) {
                  return;
              }
  
              for( ExportDataSource eds: partitionDataSourceMap.values()) {
                  try {
                      eds.acceptMastership();
                  } catch (Exception e) {
                      exportLog.error("Unable to start exporting", e);
                  }
              }
          }
      }
docs: Indicate to all associated {@link ExportDataSource} to assume
  mastership role for the given partition id
  @param partitionId