DroneRegistrar.java

/*
 * JBoss, Home of Professional Open Source
 * Copyright 2011, Red Hat Middleware LLC, and individual contributors
 * by the @authors tag. See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 *
 * 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.jboss.arquillian.drone.impl;

import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import org.jboss.arquillian.core.api.Instance;
import org.jboss.arquillian.core.api.InstanceProducer;
import org.jboss.arquillian.core.api.annotation.Inject;
import org.jboss.arquillian.core.api.annotation.Observes;
import org.jboss.arquillian.core.spi.ServiceLoader;
import org.jboss.arquillian.drone.spi.Configurator;
import org.jboss.arquillian.drone.spi.Destructor;
import org.jboss.arquillian.drone.spi.DroneRegistry;
import org.jboss.arquillian.drone.spi.Instantiator;
import org.jboss.arquillian.drone.spi.Sortable;
import org.jboss.arquillian.test.spi.annotation.SuiteScoped;
import org.jboss.arquillian.test.spi.event.suite.BeforeSuite;

/**
 * Registar of factories. Registers every {@link Configurator}, {@link Instantiator} and {@link Destructor} found via SPI.
 * Only
 * ones with highes precedence are kept. See {@link Sortable#getPrecedence()}
 * <p>
 * <p>
 * Produces:
 * </p>
 * <ol>
 * {@link DroneRegistry}
 * </ol>
 * <p>
 * <p>
 * Observes:
 * </p>
 * {@link BeforeSuite}
 *
 * @author <a href="mailto:kpiwko@redhat.com">Karel Piwko</a>
 */
public class DroneRegistrar {
    @Inject
    @SuiteScoped
    private InstanceProducer<DroneRegistry> droneRegistry;

    @Inject
    private Instance<ServiceLoader> serviceLoader;

    private static Class<?> getFirstGenericParameterType(Class<?> clazz, Class<?> rawType) {
        for (Type interfaceType : clazz.getGenericInterfaces()) {
            if (interfaceType instanceof ParameterizedType) {
                ParameterizedType ptype = (ParameterizedType) interfaceType;
                if (rawType.isAssignableFrom((Class<?>) ptype.getRawType())) {
                    return (Class<?>) ptype.getActualTypeArguments()[0];
                }
            }
        }
        return null;
    }

    public void register(@Observes BeforeSuite event) {
        droneRegistry.set(new DroneRegistryImpl());
        registerConfigurators();
        registerInstantiators();
        registerDestructors();
    }

    private void registerConfigurators() {
        @SuppressWarnings("rawtypes")
        List<Configurator> list = new ArrayList<Configurator>(serviceLoader.get().all(Configurator.class));
        Collections.sort(list, PrecedenceComparator.getReversedOrder());

        for (Configurator<?, ?> configurator : list) {
            Class<?> type = getFirstGenericParameterType(configurator.getClass(), Configurator.class);
            if (type != null) {
                droneRegistry.get().registerConfiguratorFor(type, configurator);
            }
        }
    }

    public void registerInstantiators() {
        @SuppressWarnings("rawtypes")
        List<Instantiator> list = new ArrayList<Instantiator>(serviceLoader.get().all(Instantiator.class));
        Collections.sort(list, PrecedenceComparator.getReversedOrder());

        for (Instantiator<?, ?> instantiator : list) {
            Class<?> type = getFirstGenericParameterType(instantiator.getClass(), Instantiator.class);
            if (type != null) {
                droneRegistry.get().registerInstantiatorFor(type, instantiator);
            }
        }
    }

    public void registerDestructors() {
        @SuppressWarnings("rawtypes")
        List<Destructor> list = new ArrayList<Destructor>(serviceLoader.get().all(Destructor.class));
        Collections.sort(list, PrecedenceComparator.getReversedOrder());

        for (Destructor<?> destructor : list) {
            Class<?> type = getFirstGenericParameterType(destructor.getClass(), Destructor.class);
            if (type != null) {
                droneRegistry.get().registerDestructorFor(type, destructor);
            }
        }
    }
}