MultiBindingScannerFeature.java

/**
 * Copyright (C) 2010 Daniel Manzke <daniel.manzke@googlemail.com>
 *
 * 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 de.devsurf.injection.guice.scanner.features;

import java.lang.annotation.Annotation;

import com.google.inject.binder.ScopedBindingBuilder;
import com.google.inject.multibindings.Multibinder;

import de.devsurf.injection.guice.scanner.ScannerModule;

/**
 * Default Implementation for Annotation Listeners, which should stay informed
 * abbout found annotated classes. Due the fact, that we need the Binder of the
 * Child Injector, it will be set at runtime by the {@link ScannerModule}.
 * 
 * @author Daniel Manzke
 * 
 */
public abstract class MultiBindingScannerFeature extends BindingScannerFeature {
	protected <T, V extends T> void bindInstance(V impl, Class<T> interf, Annotation annotation,
			Class<? extends Annotation> scope) {
		Multibinder<T> builder;
		synchronized (_binder) {
			if (annotation != null) {
				builder = Multibinder.newSetBinder(_binder, interf, annotation);
			} else {
				builder = Multibinder.newSetBinder(_binder, interf);
			}

			builder.addBinding().toInstance(impl);
		}
	}

	protected void bindConstant(String value, Annotation annotation) {
		Multibinder<String> builder;
		synchronized (_binder) {
			builder = Multibinder.newSetBinder(_binder, String.class, annotation);
			builder.addBinding().toInstance(value);
		}
	}

	protected <T, V extends T> void bind(Class<V> impl, Class<T> interf, Annotation annotation,
			Class<? extends Annotation> scope) {
		Multibinder<T> builder;
		synchronized (_binder) {
			if (annotation != null) {
				builder = Multibinder.newSetBinder(_binder, interf, annotation);
			} else {
				builder = Multibinder.newSetBinder(_binder, interf);
			}

			ScopedBindingBuilder scopedBindingBuilder = builder.addBinding().to(impl);
			if (scope != null) {
				scopedBindingBuilder.in(scope);
			}
		}
	}
}