GuiceBeanProvider.java

/*
 * Copyright 2011 ArcBees Inc.
 *
 * 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 com.gwtplatform.dispatch.rpc.server.guice;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import com.google.inject.Binding;
import com.google.inject.Injector;
import com.google.inject.TypeLiteral;
import com.gwtplatform.dispatch.rpc.server.actionhandlervalidator.ActionHandlerValidatorLinkerHelper.BeanProvider;
import com.gwtplatform.dispatch.rpc.server.actionhandlervalidator.ActionHandlerValidatorLinkerHelper
        .CommonBindingDescriptor;

public class GuiceBeanProvider implements BeanProvider {

    /**
     * Adapter for tranforming Guice Binding into BeanProvider implementation.
     */
    public static class GuiceBindingDescriptorAdapter<B> extends CommonBindingDescriptor<B> {

        public GuiceBindingDescriptorAdapter(Binding<B> binding) {
            super(binding.getProvider().get(), binding.getKey().toString());
        }
    }

    private final Injector injector;

    public GuiceBeanProvider(Injector injector) {
        this.injector = injector;
    }

    @Override
    public <B> B getInstance(Class<B> clazz) {
        return injector.getInstance(clazz);
    }

    @Override
    public <B> Iterator<BindingDescriptor<B>> getBindings(Class<B> clazz) {

        List<BindingDescriptor<B>> result = new ArrayList<>();

        for (Binding<B> binding : injector.findBindingsByType(TypeLiteral.get(clazz))) {
            result.add(new GuiceBindingDescriptorAdapter<>(binding));
        }

        return result.iterator();
    }
}