content: package com.ctrip.framework.apollo.spi;
  
  import java.util.Map;
  
  import com.ctrip.framework.apollo.build.ApolloInjector;
  import com.google.common.collect.Maps;
  
  /**
   * @author Jason Song(song_s@ctrip.com)
   */
  public class DefaultConfigFactoryManager implements ConfigFactoryManager {
    private ConfigRegistry m_registry;
  
    private Map<String, ConfigFactory> m_factories = Maps.newConcurrentMap();
  
    public DefaultConfigFactoryManager() {
      m_registry = ApolloInjector.getInstance(ConfigRegistry.class);
    }
  
    @Override
    public ConfigFactory getFactory(String namespace) {
      // step 1: check hacked factory
      ConfigFactory factory = m_registry.getFactory(namespace);
  
      if (factory != null) {
        return factory;
      }
  
      // step 2: check cache
      factory = m_factories.get(namespace);
  
      if (factory != null) {
        return factory;
      }
  
      // step 3: check declared config factory
      factory = ApolloInjector.getInstance(ConfigFactory.class, namespace);
  
      if (factory != null) {
        return factory;
      }
  
      // step 4: check default config factory
      factory = ApolloInjector.getInstance(ConfigFactory.class);
  
      m_factories.put(namespace, factory);
  
      // factory should not be null
      return factory;
    }
  }
  