parquet-column/src/main/java/org/apache/parquet/CorruptStatistics.java
public static boolean shouldIgnoreStatistics(String createdBy, PrimitiveTypeName columnType) {

    if (columnType != PrimitiveTypeName.BINARY && columnType != PrimitiveTypeName.FIXED_LEN_BYTE_ARRAY) {
      // the bug only applies to binary columns
      return false;
    }

    if (Strings.isNullOrEmpty(createdBy)) {
      // created_by is not populated, which could have been caused by
      // parquet-mr during the same time as PARQUET-251, see PARQUET-297
      warnOnce("Ignoring statistics because created_by is null or empty! See PARQUET-251 and PARQUET-297");
      return true;
    }

    try {
      ParsedVersion version = VersionParser.parse(createdBy);

      if (!"parquet-mr".equals(version.application)) {
        // assume other applications don't have this bug
        return false;
      }

      if (Strings.isNullOrEmpty(version.version)) {
        warnOnce("Ignoring statistics because created_by did not contain a semver (see PARQUET-251): " + createdBy);
        return true;
      }

      SemanticVersion semver = SemanticVersion.parse(version.version);

      if (semver.compareTo(PARQUET_251_FIXED_VERSION) < 0 &&
          !(semver.compareTo(CDH_5_PARQUET_251_FIXED_START) >= 0 &&
              semver.compareTo(CDH_5_PARQUET_251_FIXED_END) < 0)) {
        warnOnce("Ignoring statistics because this file was created prior to "
            + PARQUET_251_FIXED_VERSION
            + ", see PARQUET-251");
        return true;
      }

      // this file was created after the fix
      return false;
    } catch (RuntimeException e) {
      // couldn't parse the created_by field, log what went wrong, don't trust the stats,
      // but don't make this fatal.
      warnParseErrorOnce(createdBy, e);
      return true;
    } catch (SemanticVersionParseException e) {
      // couldn't parse the created_by field, log what went wrong, don't trust the stats,
      // but don't make this fatal.
      warnParseErrorOnce(createdBy, e);
      return true;
    } catch (VersionParseException e) {
      // couldn't parse the created_by field, log what went wrong, don't trust the stats,
      // but don't make this fatal.
      warnParseErrorOnce(createdBy, e);
      return true;
    }
  }
public static boolean shouldIgnoreStatistics(String createdBy, PrimitiveTypeName columnType) {

    if (columnType != PrimitiveTypeName.BINARY && columnType != PrimitiveTypeName.FIXED_LEN_BYTE_ARRAY) {
      // the bug only applies to binary columns
      return false;
    }

    if (Strings.isNullOrEmpty(createdBy)) {
      // created_by is not populated, which could have been caused by
      // parquet-mr during the same time as PARQUET-251, see PARQUET-297
      warnOnce("Ignoring statistics because created_by is null or empty! See PARQUET-251 and PARQUET-297");
      return true;
    }

    try {
      ParsedVersion version = VersionParser.parse(createdBy);

      if (!"parquet-mr".equals(version.application)) {
        // assume other applications don't have this bug
        return false;
      }

      if (Strings.isNullOrEmpty(version.version)) {
        warnOnce("Ignoring statistics because created_by did not contain a semver (see PARQUET-251): " + createdBy);
        return true;
      }

      SemanticVersion semver = SemanticVersion.parse(version.version);

      if (semver.compareTo(PARQUET_251_FIXED_VERSION) < 0 &&
          !(semver.compareTo(CDH_5_PARQUET_251_FIXED_START) >= 0 &&
              semver.compareTo(CDH_5_PARQUET_251_FIXED_END) < 0)) {
        warnOnce("Ignoring statistics because this file was created prior to "
            + PARQUET_251_FIXED_VERSION
            + ", see PARQUET-251");
        return true;
      }

      // this file was created after the fix
      return false;
    } catch (RuntimeException e) {
      // couldn't parse the created_by field, log what went wrong, don't trust the stats,
      // but don't make this fatal.
      warnParseErrorOnce(createdBy, e);
      return true;
    } catch (SemanticVersionParseException e) {
      // couldn't parse the created_by field, log what went wrong, don't trust the stats,
      // but don't make this fatal.
      warnParseErrorOnce(createdBy, e);
      return true;
    } catch (VersionParseException e) {
      // couldn't parse the created_by field, log what went wrong, don't trust the stats,
      // but don't make this fatal.
      warnParseErrorOnce(createdBy, e);
      return true;
    }
  }
Decides if the statistics from a file created by createdBy (the created_by field from parquet format)
should be ignored because they are potentially corrupt.

@param createdBy the created-by string from a file footer
@param columnType the type of the column that this is checking
@return true if the statistics may be invalid and should be ignored, false otherwise