/* 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.util;
import static org.camunda.bpm.engine.impl.util.EnsureUtil.ensureNotNull;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.List;
import org.camunda.bpm.engine.ArtifactFactory;
import org.camunda.bpm.engine.ProcessEngineException;
import org.camunda.bpm.engine.impl.bpmn.parser.FieldDeclaration;
import org.camunda.bpm.engine.impl.context.Context;
/**
* @author Roman Smirnov
*
*/
public class ClassDelegateUtil {
public static Object instantiateDelegate(Class<?> clazz, List<FieldDeclaration> fieldDeclarations) {
return instantiateDelegate(clazz.getName(), fieldDeclarations);
}
public static Object instantiateDelegate(String className, List<FieldDeclaration> fieldDeclarations) {
ArtifactFactory artifactFactory = Context.getProcessEngineConfiguration().getArtifactFactory();
try {
Class<?> clazz = ReflectUtil.loadClass(className);
Object object = artifactFactory.getArtifact(clazz);
applyFieldDeclaration(fieldDeclarations, object);
return object;
} catch (Exception e) {
throw new ProcessEngineException("couldn't instantiate class " + className, e);
}
}
public static void applyFieldDeclaration(List<FieldDeclaration> fieldDeclarations, Object target) {
if(fieldDeclarations != null) {
for(FieldDeclaration declaration : fieldDeclarations) {
applyFieldDeclaration(declaration, target);
}
}
}
public static void applyFieldDeclaration(FieldDeclaration declaration, Object target) {
Method setterMethod = ReflectUtil.getSetter(declaration.getName(),
target.getClass(), declaration.getValue().getClass());
if(setterMethod != null) {
try {
setterMethod.invoke(target, declaration.getValue());
} catch (IllegalArgumentException e) {
throw new ProcessEngineException("Error while invoking '" + declaration.getName() + "' on class " + target.getClass().getName(), e);
} catch (IllegalAccessException e) {
throw new ProcessEngineException("Illegal acces when calling '" + declaration.getName() + "' on class " + target.getClass().getName(), e);
} catch (InvocationTargetException e) {
throw new ProcessEngineException("Exception while invoking '" + declaration.getName() + "' on class " + target.getClass().getName(), e);
}
} else {
Field field = ReflectUtil.getField(declaration.getName(), target);
ensureNotNull("Field definition uses unexisting field '" + declaration.getName() + "' on class " + target.getClass().getName(), "field", field);
// Check if the delegate field's type is correct
if (!fieldTypeCompatible(declaration, field)) {
throw new ProcessEngineException("Incompatible type set on field declaration '" + declaration.getName()
+ "' for class " + target.getClass().getName()
+ ". Declared value has type " + declaration.getValue().getClass().getName()
+ ", while expecting " + field.getType().getName());
}
ReflectUtil.setField(field, target, declaration.getValue());
}
}
public static boolean fieldTypeCompatible(FieldDeclaration declaration, Field field) {
if(declaration.getValue() != null) {
return field.getType().isAssignableFrom(declaration.getValue().getClass());
} else {
// Null can be set any field type
return true;
}
}
}