package org.kuali.student.common.validator;

 import java.util.ArrayList;

 import java.util.HashMap;

 import java.util.List;

 import java.util.Map;

 import org.apache.log4j.Logger;

 /**

  * ValidatorFactory provides a mechanism to 

  *  

  * 

  * @author Kuali Rice Team (kuali-rice@googlegroups.com)

  *

  */

 public class ValidatorFactory {

         private static final Logger LOG = Logger.getLogger(ValidatorFactory.class);

         private volatile Map<String,Validator> customValidators = null; 

         private DefaultValidatorImpl defaultValidator = new DefaultValidatorImpl();

         private List<Validator> validatorList = new ArrayList<Validator>();

         public ValidatorFactory(){

                 defaultValidator.setValidatorFactory(this);

         }

         /**

          * Updated to fix double check lock not working

          * @return

          */

         public Map<String,Validator> getCustomValidators(){

                 Map<String,Validator> result = customValidators;

             if(result == null) {

                     synchronized (this) {

                             result = customValidators;

                             if(result == null){

                             result = new HashMap<String, Validator>();

                             for(Validator validator: validatorList){

                                 String validatorName = validator.getClass().getName();

                                 result.put(validatorName, validator);

                             }

                                     customValidators = result;

                             }

                         }

             }

             return result;

         }

         public Validator getValidator(String customValidator) {

                 LOG.info("Retrieving validatior:" + customValidator);

             Validator v = getCustomValidators().get(customValidator); 

             if(v != null && v instanceof BaseAbstractValidator) {

                 BaseAbstractValidator bv = (BaseAbstractValidator)v;

                 bv.setValidatorFactory(this);

                 return bv;

             } else {

                return v;

             }

         }

         public Validator getValidator(){

                 return defaultValidator;

         }

         public DefaultValidatorImpl getDefaultValidator() {

                 return defaultValidator;

         }

         public void setDefaultValidator(DefaultValidatorImpl defaultValidator) {

                 this.defaultValidator = defaultValidator;

                 this.defaultValidator.setValidatorFactory(this);

         }

     public void setValidatorList(List<Validator> validatorList) {

         this.validatorList = validatorList;

     }

 }