content: package act.inject.param;
  
  /*-
   * #%L
   * ACT Framework
   * %%
   * Copyright (C) 2014 - 2017 ActFramework
   * %%
   * 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.
   * #L%
   */
  
  import act.Destroyable;
  import act.app.App;
  import act.app.AppServiceBase;
  import act.inject.DependencyInjector;
  import act.inject.genie.GenieInjector;
  import act.util.*;
  import org.osgl.inject.BeanSpec;
  import org.osgl.util.S;
  
  import java.util.concurrent.ConcurrentMap;
  import javax.enterprise.context.ApplicationScoped;
  import javax.inject.Singleton;
  
  public class ProvidedValueLoader extends ParamValueLoader.NonCacheable {
      private DependencyInjector<?> injector;
      private BeanSpec beanSpec;
      private Object singleton;
      private ProvidedValueLoader(BeanSpec beanSpec, DependencyInjector<?> injector) {
          Class type = beanSpec.rawType();
          if (AppServiceBase.class.isAssignableFrom(type)
                  || SingletonBase.class.isAssignableFrom(type)
                  || type.isAnnotationPresent(Singleton.class)
                  || type.isAnnotationPresent(ApplicationScoped.class)) {
              singleton = injector.get(type);
          }
          this.beanSpec = beanSpec;
          this.injector = injector;
      }
  
      @Override
      public String toString() {
          return S.concat("provided loader[", bindName(), "|", beanSpec.rawType().getSimpleName(), "]");
      }
  
      @Override
      public Object load(Object bean, ActContext<?> context, boolean noDefaultValue) {
          if (null != singleton) {
              return singleton;
          }
          if (null != context && context.getClass().equals(beanSpec.rawType())) {
              return context;
          } else {
              GenieInjector genieInjector = (GenieInjector) injector;
              return genieInjector.get(beanSpec);
          }
      }
  
      @Override
      public String bindName() {
          return beanSpec.name();
      }
  
      @Override
      public boolean supportJsonDecorator() {
          return false;
      }
  
      @Override
      protected void releaseResources() {
          Destroyable.Util.tryDestroy(singleton);
          singleton = null;
          injector = null;
          lookup.clear();
      }
  
      private static ConcurrentMap<BeanSpec, ProvidedValueLoader> lookup;
  
      public static void classInit(App app) {
          lookup = app.createConcurrentMap();
      }
  
      public static ProvidedValueLoader get(BeanSpec beanSpec, DependencyInjector<?> injector) {
          ProvidedValueLoader loader = lookup.get(beanSpec);
          if (null == loader) {
              ProvidedValueLoader newLoader = new ProvidedValueLoader(beanSpec, injector);
              loader = lookup.putIfAbsent(beanSpec, newLoader);
              if (null == loader) {
                  loader = newLoader;
              }
          }
          return loader;
      }
  }
  