Validation subfranework is a set of predefine validations which encapsulates validation logic for common validation task. This framework consist of following components:-

1.Validator:- Validator are predefine classes which contends validation logic for common validation.  

2.Validation MetaData:- Validation metadata is an XML file that assign a logic name to predefine.

3.Validation Mapping:- Validation mapping is a XML file provide a application developer which associated action field to validator.

4.Validation Interceptor:- This interceptor is responsible for applying validation on action properties using predefine validators. 

 
Commonly used predefine validators:-

Required:-The required validators is used to checked wether a field has some value or not. Empty string are considered value by this validators.

Requiredstring:-Same as required accept empty string are not concerned value.

Int ,double and date:-Are used to checked weather an integer, real, number or date is within range or not.

Email:-This interceptor is used to checked weather a mailed is proper formate or not.

URL :- The url interceptor is used to checked weather a url is proper formate or not.

Stringlength:-The Stringlength is used to checked weather length of string lies within range or not.

Regex:-The regex interceptor is used to checked value of a field using a regular expiration. 




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