/*
* Copyright (c) 2005-2011 Grameen Foundation USA
* All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
* implied. See the License for the specific language governing
* permissions and limitations under the License.
*
* See also http://www.apache.org/licenses/LICENSE-2.0.html for an
* explanation of the license and how it is applied.
*/
package org.mifos.framework.formulaic;
/*
* If input is null, this validator returns null. Otherwise, returns
* the output of passing the input through the contained validator.
* Useful for indicating that field is optional, but if it is given it must
* meet certain constraints
*/
public class NullValidator extends BaseValidator {
private Validator otherValidator;
public NullValidator(Validator otherValidator) {
this.otherValidator = otherValidator;
}
public NullValidator() {
this(new IdentityValidator());
}
@Override
public Object validate(Object value) throws ValidationError {
if (value == null) {
return null;
} else {
return otherValidator.validate(value);
}
}
}