Grails contains really great Validators that you can use in your constraints. But it is missing one that I need for a project I am working on, . . . There is no PhoneNumber constraint. Luckily, I ran across Geoff Lane's Post: Build a Custom Validator in Grails with a Plugin
In Chapter 2 Regular Expressions section of Beginning Groovy and Grails, we show using a regular expression to validate phone numbers. Well, now I had all of the parts required to make a PhoneNumber Custom Validator.
Usage:
class party {
String name
String workPhone
static constraints = = {
workPhone(phoneNumber:true)
}
The Constraint:
import org.codehaus.groovy.grails.validation.AbstractConstraint
import org.springframework.validation.Errors
/**
* Phone Number Constraint
*
* The phone number constraint is used to validate phone number formats
*
* Registering the Constraint.
*
* App Registration Config.groovy
*
* org.codehaus.groovy.grails.validation.ConstrainedProperty.registerNewConstraint(
* PhoneNumberConstraint.NAME, PhoneNumberConstraint.class)
*
*
* Plugin Registration MyPlugin.groovy:
*
* def doWithSpring = {
* ConstrainedProperty.registerNewConstraint(PhoneNumberConstraint.NAME, PhoneNumberConstraint.class);
* }
*
*
* This plugin is based upon the following posts:
*
* http://www.zorched.net/2008/01/25/build-a-custom-validator-in-grails-with-a-plugin/
* http://www.zorched.net/2008/01/26/custom-validators-in-grails-in-a-single-app/
*
* @author Jim Shingler ShinglerJim at gmail.com
*/
class PhoneNumberConstraint extends AbstractConstraint {
private static final String DEFAULT_MESSAGE_CODE = "default.phoneNumber.invalid.message";
public static final String NAME = "phoneNumber";
private boolean validateConstraint
public void setParameter(Object constraintParameter) {
if (!(constraintParameter instanceof Boolean))
throw new IllegalArgumentException("Parameter for constraint ["
+ NAME + "] of property ["
+ constraintPropertyName + "] of class ["
+ constraintOwningClass + "] must be a boolean value");
this.validateConstraint = ((Boolean) constraintParameter).booleanValue()
super.setParameter(constraintParameter);
}
protected void processValidate(Object target, Object propertyValue, Errors errors) {
if (validateConstraint && !validate(target, propertyValue)) {
def args = (Object[]) [constraintPropertyName, constraintOwningClass,
propertyValue]
super.rejectValue(target, errors, DEFAULT_MESSAGE_CODE,
"not." + NAME, args);
}
}
boolean supports(Class type) {
return type != null && String.class.isAssignableFrom(type);
}
String getName() {
return NAME;
}
/**
* This is where the real work is. Use a regular expression to validate
* the phone number.
*
* The core logic of the constraint is implemented as its own method to make the
* constraint easier to test.
*/
boolean validate(target, propertyValue) {
propertyValue ==~ /^[01]?\s*[\(\.-]?(\d{3})[\)\.-]?\s*(\d{3})[\.-](\d{4})$/
}
}
The real work is in the validate function.
As you can see, creating a custom constraint is really pretty easy. Just make sure that you follow the directions in the constraint class comments to register the constraint.
