Apache Struts 2 Documentation > Home > Guides > Core Developers Guide > Validation > stringlength validator |
StringLengthFieldValidator checks that a String field is of a certain length. If the "minLength" parameter is specified, it will make sure that the String has at least that many characters. If the "maxLength" parameter is specified, it will make sure that the String has at most that many characters. 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.
<validators> <!-- Plain Validator Syntax --> <validator type="stringlength"> <param name="fieldName">myPurchaseCode</param> <param name="minLength">10</param> <param name="maxLength">10</param> <param name="trim">true</param> <message>Your purchase code needs to be 10 characters long</message> </validator> <!-- Field Validator Syntax --> <field name="myPurchaseCode"> <param name="minLength">10</param> <param name="maxLength>10</param> <param name="trim">true</param> <message>Your purchase code needs to be 10 characters long</message> </field-name> </validators>