Validations in Liferay

When we are going to submit form data or going to perform any action on form data the before submitting form successfully we are doing validations.

There are two types of validation :

1. Client Side Validation
2. Server Side validation

CLIENT SIDE VALIDATION

Client validation performed using java script in the form. We can do client side validation using   jQuery validator, AUI validator. etc

Liferay also have one of the tag called <aui:validator/> to perform client side validations using AUI. 
For complex client side validation we can write  <aui:script></aui:script> also using AUI.

SERVER SIDE VALIDATION

Some time we need to check the form data(user data) with existed data which is in database.
In such case we need  server side validations.

Generally server side validation performed after submittion of  form to the controller and there we will validate the data with database, based on that we will send errors back to the form after clearing validation then we are allowing to proceed further.

Examples of Server Side Validation

Example 1