/* 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.
*/
package org.camunda.bpm.engine.impl.form.validator;
import java.util.HashMap;
import java.util.Map;
import org.camunda.bpm.engine.ProcessEngineConfiguration;
import org.camunda.bpm.engine.ProcessEngineException;
import org.camunda.bpm.engine.delegate.Expression;
import org.camunda.bpm.engine.impl.bpmn.parser.BpmnParse;
import org.camunda.bpm.engine.impl.el.ExpressionManager;
import org.camunda.bpm.engine.impl.util.StringUtil;
import org.camunda.bpm.engine.impl.util.xml.Element;
/**
* <p>Registry for built-in {@link FormFieldValidator} implementations.</p>
*
* <p>Factory for {@link FormFieldValidator} instances.</p>
*
* @author Daniel Meyer
*
*/
public class FormValidators {
/** the registry of configured validators. Populated through {@link ProcessEngineConfiguration}. */
protected Map<String, Class<? extends FormFieldValidator>> validators = new HashMap<String, Class<? extends FormFieldValidator>>();
/**
* factory method for creating validator instances
*
*/
public FormFieldValidator createValidator(Element constraint, BpmnParse bpmnParse, ExpressionManager expressionManager) {
String name = constraint.attribute("name");
String config = constraint.attribute("config");
if("validator".equals(name)) {
// custom validators
if(config == null || config.isEmpty()) {
bpmnParse.addError("validator configuration needs to provide either a fully " +
"qualified classname or an expression resolving to a custom FormFieldValidator implementation.",
constraint);
} else {
if(StringUtil.isExpression(config)) {
// expression
Expression validatorExpression = expressionManager.createExpression(config);
return new DelegateFormFieldValidator(validatorExpression);
} else {
// classname
return new DelegateFormFieldValidator(config);
}
}
} else {
// built-in validators
Class<? extends FormFieldValidator> validator = validators.get(name);
if(validator != null) {
FormFieldValidator validatorInstance = createValidatorInstance(validator);
return validatorInstance;
} else {
bpmnParse.addError("Cannot find validator implementation for name '"+name+"'.", constraint);
}
}
return null;
}
protected FormFieldValidator createValidatorInstance(Class<? extends FormFieldValidator> validator) {
try {
return validator.newInstance();
} catch (InstantiationException e) {
throw new ProcessEngineException("Could not instantiate validator", e);
} catch (IllegalAccessException e) {
throw new ProcessEngineException("Could not instantiate validator", e);
}
}
public void addValidator(String name, Class<? extends FormFieldValidator> validatorType) {
validators.put(name, validatorType);
}
public Map<String, Class<? extends FormFieldValidator>> getValidators() {
return validators;
}
}