@Override
    public void getMetaSummary(Map<String, String> properties, MetadataTableSummary summary) {
      SummaryMapBuilder builder = new SummaryMapBuilder()
          .add(WRITE_MERGE_MODE, properties.getOrDefault(WRITE_MERGE_MODE, COPY_ON_WRITE))
          .add(WRITE_DELETE_MODE, properties.getOrDefault(WRITE_DELETE_MODE, COPY_ON_WRITE))
          .add(WRITE_UPDATE_MODE, properties.getOrDefault(WRITE_UPDATE_MODE, COPY_ON_WRITE));
      if (formatJson) {
        summary.addExtra("CoW/MoR", builder);
      } else {
        summary.addExtra(builder);
      }
    }
Collect the summary based on the table's properties.
It could be the version, write mode or compression, etc.
iceberg/iceberg-handler/src/main/java/org/apache/iceberg/metasummary/TablePropertySummary.java