content: /*
   * Copyright (C) 2020 ActiveJ LLC.
   *
   * 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 io.activej.inject.impl;
  
  import java.util.concurrent.atomic.AtomicReferenceArray;
  
  @SuppressWarnings("rawtypes")
  public abstract class AbstractCompiledBinding<R> implements CompiledBinding<R> {
  	protected final int scope;
  
  	protected final int index;
  
  	protected AbstractCompiledBinding(int scope, int index) {
  		this.scope = scope;
  		this.index = index;
  	}
  
  	@SuppressWarnings("unchecked")
  	@Override
  	public final R getInstance(AtomicReferenceArray[] scopedInstances, int synchronizedScope) {
  		AtomicReferenceArray array = scopedInstances[scope];
  		R instance = (R) array.get(index);
  		if (instance != null) return instance;
  		if (synchronizedScope == scope) {
  			instance = doCreateInstance(scopedInstances, synchronizedScope);
  			array.set(index, instance);
  			return instance;
  		}
  		//noinspection SynchronizationOnLocalVariableOrMethodParameter
  		synchronized (array) {
  			instance = (R) array.get(index);
  			if (instance != null) return instance;
  			instance = doCreateInstance(scopedInstances, scope);
  			array.set(index, instance);
  			return instance;
  		}
  	}
  
  	protected abstract R doCreateInstance(AtomicReferenceArray[] scopedInstances, int synchronizedScope);
  }
  