cdi-extender/src/main/java/org/apache/aries/cdi/container/internal/provider/CDIProvider.java

/**
 * 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.apache.aries.cdi.container.internal.provider;

import java.lang.annotation.Annotation;
import java.util.Collections;
import java.util.Iterator;
import java.util.Optional;

import javax.enterprise.inject.Instance;
import javax.enterprise.inject.spi.BeanManager;
import javax.enterprise.inject.spi.CDI;
import javax.enterprise.util.TypeLiteral;

import org.apache.aries.cdi.container.internal.Activator;
import org.osgi.framework.Bundle;
import org.osgi.framework.BundleReference;

public class CDIProvider implements javax.enterprise.inject.spi.CDIProvider {

	private static class CdiExtenderCDI extends CDI<Object> {

		@Override
		public void destroy(Object instance) {
			// NOOP
		}

		@Override
		public Object get() {
			return this;
		}

		@Override
		public BeanManager getBeanManager() {
			ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader();

			if (contextClassLoader instanceof BundleReference) {
				BundleReference br = (BundleReference)contextClassLoader;

				Bundle bundle = br.getBundle();

				return Optional.ofNullable(
					Activator.ccr.getContainerState(bundle)
				).map(
					cs -> cs.beanManager()
				).orElse(null);
			}

			throw new IllegalStateException(
				"This method can only be used when the Thread context class loader has been set to a Bundle's classloader.");
		}

		@Override
		public boolean isAmbiguous() {
			return false;
		}

		@Override
		public boolean isUnsatisfied() {
			return false;
		}

		@Override
		public Iterator<Object> iterator() {
			return Collections.singleton((Object)this).iterator();
		}

		@Override
		public Instance<Object> select(Annotation... qualifiers) {
			return getBeanManager().createInstance().select(qualifiers);
		}

		@Override
		public <U> Instance<U> select(Class<U> subtype, Annotation... qualifiers) {
			return getBeanManager().createInstance().select(subtype, qualifiers);
		}

		@Override
		public <U> Instance<U> select(TypeLiteral<U> subtype, Annotation... qualifiers) {
			return getBeanManager().createInstance().select(subtype, qualifiers);
		}

	}

	private static final CDI<Object> _cdi = new CdiExtenderCDI();

	@Override
	public CDI<Object> getCDI() {
		return _cdi;
	}

}