grib/src/main/java/ucar/nc2/grib/grib1/Grib1SectionGridDefinition.java
public long calcCRC() {
    long crc;
    if (rawData == null)
      crc = predefinedGridDefinitionCenter << 16 + predefinedGridDefinition;
    else {
      CRC32 crc32 = new CRC32();
      crc32.update(rawData);
      crc = crc32.getValue();
    }
    return crc;
  }
public long calcCRC() {
    long crc;
    if (rawData == null)
      crc = predefinedGridDefinitionCenter << 16 + predefinedGridDefinition;
    else {
      CRC32 crc32 = new CRC32();
      crc32.update(rawData);
      crc = crc32.getValue();
    }
    return crc;
  }
Calculate the CRC of the entire byte array

@return CRC  of the entire byte array