text: // /////////////////////////////////////////////////////////
  // This file is part of Propel.
  //
  // Propel is free software: you can redistribute it and/or modify
  // it under the terms of the GNU Lesser General Public License as published by
  // the Free Software Foundation, either version 3 of the License, or
  // (at your option) any later version.
  //
  // Propel is distributed in the hope that it will be useful,
  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  // GNU Lesser General Public License for more details.
  //
  // You should have received a copy of the GNU Lesser General Public License
  // along with Propel. If not, see <http://www.gnu.org/licenses/>.
  // /////////////////////////////////////////////////////////
  // Authored by: Nikolaos Tountas -> salam.kaser-at-gmail.com
  // /////////////////////////////////////////////////////////
  package propel.core.validation.propertyMetadata;
  
  import propel.core.common.CONSTANT;
  import propel.core.configuration.ConfigurableConsts;
  import propel.core.configuration.ConfigurableParameters;
  import propel.core.utils.StringComparison;
  import propel.core.utils.StringUtils;
  import propel.core.validation.ValidationException;
  
  /**
   * Class aiding in validation of IPv6 addresses
   */
  public class IpV6AddressPropertyMetadata
      extends EncodedStringPropertyMetadata
  {
    /**
     * The max number of hex groups expected in an IPv6 address
     */
    public static final int MAX_NUM_HEX_GROUPS = 8;
    /**
     * Error message when an IPv6 has an invalid number of colon separators
     */
    public static final String IP_INVALID_NUMBER_OF_COLONS = "%s has an invalid number of IPv6 group-separator colons: ";
    /**
     * Error message when an IPv6 has an invalid number of double colon instances
     */
    public static final String IP_INVALID_NUMBER_OF_DOUBLE_COLONS = "%s has an invalid number of IPv6 group-separator double-colons: ";
    /**
     * Error message when an IPv6 has an invalid number of groups
     */
    public static final String IP_INVALID_NUMBER_OF_GROUPS = "%s has an invalid number of IPv6 groups: ";
    /**
     * The default minimum IPv6 length
     */
    public static final int DEFAULT_MIN_IPV6_LENGTH = ConfigurableParameters.getInt32(ConfigurableConsts.VALIDATION_DEFAULT_MIN_IPV6_LENGTH);
    /**
     * The default maximum IPv6 length
     */
    public static final int DEFAULT_MAX_IPV6_LENGTH = ConfigurableParameters.getInt32(ConfigurableConsts.VALIDATION_DEFAULT_MAX_IPV6_LENGTH);
  
    /**
     * Default constructor
     */
    protected IpV6AddressPropertyMetadata()
    {
    }
  
    /**
     * Constructor initializes with RFC-specified constraints
     * 
     * @throws IllegalArgumentException An argument is invalid
     */
    public IpV6AddressPropertyMetadata(String name, boolean notNull, boolean notEmpty)
    {
      this(name, ConfigurableParameters.tryGetIterable(ConfigurableConsts.VALIDATION_ALLOWED_IPV6_CHARS), DEFAULT_MIN_IPV6_LENGTH,
          DEFAULT_MAX_IPV6_LENGTH, notNull, notEmpty);
    }
  
    /**
     * Constructor initializes with custom constraints
     * 
     * @throws IllegalArgumentException An argument is invalid
     */
    public IpV6AddressPropertyMetadata(String name, Iterable<Character> allowedChars, int minLength, int maxLength, boolean notNull,
                                       boolean notEmpty)
    {
      super(name, allowedChars, minLength, maxLength, notNull, notEmpty, true);
    }
  
    /**
     * {@inheritDoc}
     */
    @Override
    public String validate(String value)
        throws ValidationException
    {
      value = super.validate(value);
  
      if (value != null)
        checkIpAddress(value);
  
      return value;
    }
  
    protected void checkIpAddress(String value)
        throws ValidationException
    {
      // count number of colons, up to 8
      int numOfColons = StringUtils.count(value, CONSTANT.COLON_CHAR);
  
      if ((numOfColons >= 2) && (numOfColons <= MAX_NUM_HEX_GROUPS - 1))
      {
        // count number of double colons, must be 1
        int numOfDoubleColons = StringUtils.count(value, CONSTANT.DOUBLE_COLON, StringComparison.Ordinal);
  
        String[] groups;
        // substitute double cols with group of 4 zeroes
        if (numOfDoubleColons == 1)
        {
          groups = new String[MAX_NUM_HEX_GROUPS];
          for (int i = 0; i < MAX_NUM_HEX_GROUPS; i++)
            groups[i] = CONSTANT.ZERO;
          // where we put them depends on the double colon position
          if (value.startsWith(CONSTANT.DOUBLE_COLON))
          {
            String[] lastGroups = StringUtils.split(value.substring(CONSTANT.DOUBLE_COLON.length()), CONSTANT.COLON_CHAR);
            System.arraycopy(lastGroups, 0, groups, MAX_NUM_HEX_GROUPS - lastGroups.length, lastGroups.length);
          } else if (value.endsWith(CONSTANT.DOUBLE_COLON))
          {
            String[] firstGroups = StringUtils
                .split(value.substring(0, value.length() - CONSTANT.DOUBLE_COLON.length()), CONSTANT.COLON_CHAR);
            System.arraycopy(firstGroups, 0, groups, 0, firstGroups.length);
          } else
          {
            int index = value.indexOf(CONSTANT.DOUBLE_COLON);
            String[] firstGroups = StringUtils.split(value.substring(0, index), CONSTANT.COLON_CHAR);
            System.arraycopy(firstGroups, 0, groups, 0, firstGroups.length);
            String[] lastGroups = StringUtils.split(value.substring(index + CONSTANT.DOUBLE_COLON.length()), CONSTANT.COLON_CHAR);
            System.arraycopy(lastGroups, 0, groups, MAX_NUM_HEX_GROUPS - lastGroups.length, lastGroups.length);
          }
        } else if (numOfDoubleColons == 0)
          groups = StringUtils.split(value, CONSTANT.COLON_CHAR);
        else
          throw new ValidationException(String.format(IP_INVALID_NUMBER_OF_DOUBLE_COLONS, getName()) + numOfDoubleColons);
  
        // must have 8 groups
        if (groups.length != MAX_NUM_HEX_GROUPS)
          throw new ValidationException(String.format(IP_INVALID_NUMBER_OF_GROUPS, getName()) + groups.length);
      } else
        throw new ValidationException(String.format(IP_INVALID_NUMBER_OF_COLONS, getName()) + numOfColons);
    }
  }
  