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    * wcm.io
    * %%
    * Copyright (C) 2015 wcm.io
    * %%
    * 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.
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  package io.wcm.caravan.io.http.impl.ribbon;
  
  import org.apache.felix.scr.annotations.Component;
  import org.apache.felix.scr.annotations.Property;
  import org.apache.felix.scr.annotations.Service;
  
  import com.netflix.client.ClientFactory;
  import com.netflix.client.config.CommonClientConfigKey;
  import com.netflix.client.config.DefaultClientConfigImpl;
  import com.netflix.client.config.IClientConfig;
  import com.netflix.loadbalancer.ILoadBalancer;
  
  import io.wcm.caravan.io.http.RequestInstantiationRuntimeException;
  
  /**
   * Simple implementation for the Ribbon load balancer factory. Uses Netflix OSS configuration infrastructure.
   */
  @Component
  @Service(LoadBalancerFactory.class)
  @Property(name = "type", value = LoadBalancerFactory.SIMPLE)
  public class SimpleLoadBalancerFactory implements LoadBalancerFactory {
  
    @Override
    public ILoadBalancer getLoadBalancer(String serviceId) {
  
      try {
        IClientConfig clientConfig = ClientFactory.getNamedConfig(serviceId, DefaultClientConfigImpl.class);
        String loadBalancerClassName = clientConfig.get(CommonClientConfigKey.NFLoadBalancerClassName);
        return (ILoadBalancer)ClientFactory.instantiateInstanceWithClientConfig(loadBalancerClassName, clientConfig);
      }
      catch (NullPointerException | InstantiationException | IllegalAccessException | ClassNotFoundException ex) {
        throw new RequestInstantiationRuntimeException("Can't create LoadBalancer for " + serviceId, ex);
      }
    }
  
  }