Programming Tutorials

Simple example of using the requiredif Validator rule in Struts

By: Apache Foundation in Struts Tutorials on 2008-09-20  

First off, there's an even newer Validator rule called validwhen, which is almost certainly what you want to use, since it is much easier and more powerful. It will be available in the first release after 1.1 ships. The example shown below could be coded with validwhen as:

<form name="medicalStatusForm">

<field
    property="pregnancyTest" depends="validwhen">
  <arg0 key="medicalStatusForm.pregnancyTest.label"/>
  <var>
    <var-name>test</var-name>
    <var-value>((((sex == 'm') OR (sex == 'M')) AND (*this* == null)) OR (*this* != null))</test>
  </var>
</field>

Let's assume you have a medical information form with three fields, sex, pregnancyTest, and testResult. If sex is 'f' or 'F', pregnancyTest is required. If pregnancyTest is not blank, testResult is required. The entry in your validation.xml file would look like this:

<form name="medicalStatusForm">

<field
    property="pregnancyTest" depends="requiredif">
  <arg0 key="medicalStatusForm.pregnancyTest.label"/>
  <var>
    <var-name>field[0]</var-name>
    <var-value>sex</var-value>
  </var>
  <var>
    <var-name>fieldTest[0]</var-name>
    <var-value>EQUAL</var-value>
  </var>
  <var>
    <var-name>fieldValue[0]</var-name>
    <var-value>F</var-value>
  </var>
  <var>
    <var-name>field[1]</var-name>
    <var-value>sex</var-value>
  </var>
  <var>
    <var-name>fieldTest[1]</var-name>
    <var-value>EQUAL</var-value>
  </var>
  <var>
    <var-name>fieldValue[1]</var-name>
    <var-value>f</var-value>
  </var>
  <var>
    <var-name>fieldJoin</var-name>
    <var-value>OR</var-value>
  </var>
</field>

<field
    property="testResult" depends="requiredif">
  <arg0 key="medicalStatusForm.testResult.label"/>
  <var>
    <var-name>field[0]</var-name>
    <var-value>pregnancyTest</var-value>
  </var>
  <var>
    <var-name>fieldTest[0]</var-name>
    <var-value>NOTNULL</var-value>
  </var>
</field>
</form>