requiredstring validator
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requiredstring validator
Description
Parameters
Examples
Description
RequiredStringValidator checks that a String field is non-null and has a length &gt; 0. (i.e. it isn’t “”). The trim parameter
determines whether it will String#trim() the String before performing the length check. If unspecified, the String will be trimmed.
Parameters
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.
Examples
&lt;validators&gt;
&lt;!-- Plain-Validator Syntax --&gt;
&lt;validator type="requiredstring"&gt;
&lt;param name="fieldName"&gt;username&lt;/param&gt;
&lt;param name="trim"&gt;true&lt;/param&gt;
&lt;message&gt;username is required&lt;/message&gt;
&lt;/validator&gt;
&lt;!-- Field-Validator Syntax --&gt;
&lt;field name="username"&gt;
&lt;field-validator type="requiredstring"&gt;
&lt;param name="trim"&gt;true&lt;/param&gt;
&lt;message&gt;username is required&lt;/message&gt;
&lt;/field-validator&gt;
&lt;/field&gt;
&lt;!-- Field-Validator Syntax with expression --&gt;
&lt;field name="username"&gt;
&lt;field-validator type="requiredstring"&gt;
&lt;param name="trimExpression"&gt;${trimValue}&lt;/param&gt; &lt;!-- will be evaluated as: boolean getTrimValue() --&gt;
&lt;message&gt;username is required&lt;/message&gt;
&lt;/field-validator&gt;
&lt;/field&gt;
&lt;/validators&gt;
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