You can implement server side validations using specific java classes and configuring the wizard to execute them before / after processing a wizard step. You can achieve this by using “beforeVK” and “afterVK” attributes of <action> tag. You need to provide a key as the value for these attributes. The corresponding key should be declared in any <*-service>.properties file specifying the java class which will perform the validations and return the result. For example:

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