code: public static boolean isValidStringMinLength(final GraphObject node, final PropertyKey<String> key, final int minLength, final ErrorBuffer errorBuffer) {
  
  		String value = node.getProperty(key);
  		String type  = node.getType();
  
  		if (StringUtils.isNotBlank(value)) {
  
  			if (value.length() >= minLength) {
  
  				return true;
  
  			}
  
  			errorBuffer.add(new TooShortToken(type, key, minLength));
  			return false;
  
  		}
  
  		errorBuffer.add(new EmptyPropertyToken(type, key));
  		return false;
  	}
docs: Checks whether the value for the given property key of the given node
  has at least the given length.
  
  @param node the node
  @param key the property key whose value should be checked
  @param minLength the min length
  @param errorBuffer the error buffer
  
  @return true if the condition is valid