Built in validators

Function name	Requirement to processed value parameter
areIn(List values, List list)	is a list which values are equal to any member of the specified list
areIn(List values, Set set)	is a list which values are equal to any member of the specified set
contains(String value, CharSequence substring)	contains the specified the specified sequence of char values
endsWith(String value, String suffix)	ends with the specified suffix
isAfter(Date value, Date minDate)	is a date after the specified one
isAfterNow(Date value)	is a date after now
isAlnum(String value)	is a string that matches /[a-zA-Z0-9]+/
isAlnumSpace(String value)	is a string that matches /[a-zA-Z0-9\s]+/
isAlpha(String value)	is a string that matches /[a-zA-Z]+/
isAlphaSpace(String value)	is a string that matches /[a-zA-Z\s]+/
isAny(List values)	is a list whose at least one member is true according to the Groovy Truth
isAny(List values, Closure closure)	is a list whose at least one member is valid according to a predicate
isBefore(Date value, Date maxDate)	is a date before the specified one
isBeforeNow(Date value)	is a date before now
isBetween(Number value, Number min, Number max)	falls within the specified range of decimal values
isBetween(Integer value, IntRange min..max)	falls within the specified integer range (uses HTML5 min and max attributes for the client side [18])
isBirthDateAlive(Date value)	is a date before the current year (or the current year) but not more than 120 years in the past
isBirthYearAlive(Integer year)	is a year before the current year (or the current year) but not more than 120 years in the past
isEmail(String value)	is an email address compliant to RFC [21] (uses the HTML5 email input type for the client side)
isEmpty(List values)	is an empty list
isEmpty(String value)	is a string that matches /\s*/
isEqual(value, object) (alias eq)	is equal to the specified object
isEven(Long value)	is an even number
isEvery(List values)	is a list whose members are true according to the Groovy Truth
isEvery(List values, Closure closure)	is a list whose members are valid according to a predicate
isFalse(value)	coerces to boolean false
isGreater(Number value, Number number) (alias ‒ gt)	is a number greater than the specified number
isGreaterEq(Number value, Number number)  (alias ‒ gte)	is a number greater or equal to the specified number
isIn(value, List list)	is equal to any member of the specified list
isIn(value, Set set)	is equal to any member of the specified set
isLengthEq(String value, Integer length)	has the specified string length
isLengthBetween(String value, Integer min, Integer max)	is within the specified range of string lengths (the range is inclusive)
isLengthLess(String value, Integer length)	has a string length less than specified value
isLengthLessEq(String value, Integer length)	has a string length less or equal to specified value
isLengthMore(String value, Integer length)	has a string length more than specified value
isLengthMoreEq(String value, Integer length)	has a string length more than or equal to the specified value
isLess(Number value, Number number) (alias: lt)	is a number less than the specified number
isLessEq(Number value, Number number) (alias: lte)	is a number less than or equal to the specified number
isOdd(Long value)	is an odd number
isStrongPassword(String value, List<String> mediumPasswordRegexes, List<String> strongPasswordRegexes)	is compliant with a strong password policy A password is: - weak if it does not match some of mediumPasswordRegexes - medium if it does not match some of strongPasswordRegexes - strong if it matches all the given regexes Password is invalid if it is not strong, in this case ValidationException’s parameters field contains password strength (WEAK or MEDIUM), which then can be read on the client side
isTrue(value)	coerces to boolean true
matches(String value, String regexp)	is a string that matches the specified regex (uses HTML5 attribute pattern for the client side [25])
startsWith(String value, String prefix)	starts with the specified prefix