es.indaba.jdbc.annotations.impl.AnnotationInterfaceObjectFactory.java Source code

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Here is the source code for es.indaba.jdbc.annotations.impl.AnnotationInterfaceObjectFactory.java

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/*******************************************************************************
 *  This program is free software: you can redistribute it and/or modify it under
 *  the terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation, either version 3 of the License, or (at your option) any
 *  later version. This program is distributed in the hope that it will be
 *  useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
 *  Public License for more details. You should have received a copy of the GNU
 *  Lesser General Public License along with this program. If not, see
 *  <http://www.gnu.org/licenses/>
 *  
 *******************************************************************************/
package es.indaba.jdbc.annotations.impl;

import java.lang.annotation.Annotation;
import java.lang.reflect.Method;

import javax.enterprise.inject.spi.BeanManager;
import javax.persistence.EntityManager;

import org.apache.deltaspike.core.api.provider.BeanManagerProvider;
import org.apache.deltaspike.core.api.provider.BeanProvider;
import org.apache.deltaspike.core.util.AnnotationUtils;
import org.apache.deltaspike.core.util.metadata.AnnotationInstanceProvider;
import org.hibernate.Session;

import es.indaba.jdbc.annotations.api.DatabaseCall;
import javassist.util.proxy.MethodHandler;
import javassist.util.proxy.ProxyFactory;

@SuppressWarnings("rawtypes")
public class AnnotationInterfaceObjectFactory<T> {

    public Class buildClass(Class<T> type) {

        ProxyFactory factory = new ProxyFactory();
        factory.setInterfaces(new Class[] { type });
        factory.setHandler(new MethodHandler() {

            public Object invoke(Object arg0, Method method, Method arg2, Object[] parameters) throws Throwable {

                BeanManager beanManager = BeanManagerProvider.getInstance().getBeanManager();
                Annotation[] annotations = method.getAnnotations();
                DatabaseCall dbCall = AnnotationUtils.findAnnotation(beanManager, annotations, DatabaseCall.class);
                if (dbCall == null)
                    return null;

                GenericWork callWork = AnnotationProcessor.buildWork(method, parameters);
                if (callWork == null)
                    return null;
                // Get EM based on provided qualifier
                EntityManager manager = BeanProvider.getContextualReference(EntityManager.class, false,
                        AnnotationInstanceProvider.of(dbCall.qualifier()));
                Session delegate = (Session) manager.getDelegate();

                delegate.doWork(callWork);

                return callWork.getResultObject();
            }
        });

        Class c = factory.createClass();
        return c;
    }

    @SuppressWarnings("unchecked")
    public T getInstance(Class<T> c) throws InstantiationException, IllegalAccessException {
        Class derived = buildClass(c);
        return (T) derived.newInstance();
    }
}