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RequiredStringValidator checks that a String field is non-null and has a length > 0. (i.e. it isn't ""). The "trim" parameter determines whether it will {@link String#trim() trim} the String before performing the length check. If unspecified, the String will be trimmed.


  • fieldName - The field name this validator is validating. Required if using Plain-Validator Syntax otherwise not required
  • trim - (Optional) Boolean, default true. Trims the field name value before validating.
  • trimExpression - (Optional) String. Specifies the trim param as an OGNL expression.