Apache Commons Validator helps you with common issues when receiving data either electronically or from user input and verifying the integrity of that data. This work is repetitive and becomes even more complicated when different sets of validation rules need to be applied to the same set of data based on locale. Error messages may also vary by locale. This package addresses some of these issues to speed development and maintenance of validation rules.
Commons Validator provides two distinct sets of functionality:
Your validation methods are plugged into the engine and executed against your data. Often, these methods use resources specific to one application or framework so Commons Validator doesn't directly provide pluggable validator actions. However, it does have a set of common validation methods (email addresses, dates, URLs, etc.) that help in creating pluggable actions.
In order to use the Validator, the following basic steps are required:
org.apache.commons.validator.Validator class. Currently Validator instances may be safely reused if the
current ValidatorResources are the same, as long as you have completed any previous validation, and you do not try to utilize a particular Validator
instance from more than one thread at a time.
org.apache.commons.validator.Validator.