Struts2 Framework: Built-in Data Validators

List of Some Built-in Data Validators

Validator Name	Class Name	Validation
required	RequiredFieldValidator	If field is not null
requiredstring	RequirredStringValidator	If string not-null and contains length > 0
stringlength validator	StringLengthFieldValidator	If String field is of a certain length based on minlenth and maxlength specified
email validator	EmailValidator	If field contains valid email address
date validator	DateRangeFieldValidator	if the date field is within a specified parameter range
conditionalvisitor	ConditionalVisitorFieldValidator	Conditional validator will forward the request to the conditionalfield validator if the expression is true
Expression	ExpressionValidator	Validated based on regular expression supplied
fieldExpression	FieldExpressionValidator	Validates a field based on OGNL expression
Double	DoubleRangeFieldValidator	if double within a certain range
url	URLValidator	If the field value is valid URL
regex	RegexFieldValidator	Validates a field based on regular expression

Struts2 Framework Annotation Based Validators

List of Annotation Based Validators

Annotation Name	Validation
@RequiredStringValidator	If the string is not null and length > 0
@RequiredFieldValidator	If the string is not null
@EmailValidator	If the field is valid email address
@RegexFieldValidator	If the field matches the provided regular expression
@IntRangeFieldValidator	If the numeric field is within specified range
@StringLengthFieldValidator	If the field length is within the specified minimum and maximum length
@DateRangeFieldValidator	If the date field is within specified range
@FieldExpressionValidator	If the field matches the provided OGNL expression
Double	DoubleRangeFieldValidator
url	URLValidator
regex	RegexFieldValidator