private static int buildVersionNumber(int major, int minor, int patch) {
    return (major << 20) | (minor << 12) | patch;
  }
Pack the full number version in a int. by shifting each component by 8bit, except the dot
release which has 12bit. Examples: (1.3.4 is 0x0103004, 2.1.0 is 0x0201000)
@param major version major number
@param minor version minor number
@param patch version patch number
@return the version number as int. (e.g. 0x0103004 is 1.3.4)
hbase-server/src/main/java/org/apache/hadoop/hbase/client/VersionInfoUtil.java