There can be defined conditions, for which a change to the next panel in the installation wizard is allowed.

This can be achieved by a nested definition into the panel definition od the installer descriptor:

<panels>
    ...
    <panel classname="TargetPanel">
      <validator classname="com.izforge.izpack.installer.validator.ConditionValidator"/>
    </panel>
    ...
</panels>

There can be used built-in or user-defined data validators.

There can be any number of validators nested to a <panel> definition. All of them must validate successfully (or their condition must evaluate false) to allow a final success and thus a panel change from the according panel.

A <validator> tag takes the following attributes:

AttributeDescriptionValuesRequired
className

Fully qualified classname of an Validator implementation.

This can be a built-in validator or one from additional libraries in the <jar> tag.

Stringyes
conditionCondition for applying this validator. If this condition evaluates false, the according validator is ignoredStringno