content: package backtype.storm.transactional.state;
  
  import backtype.storm.Config;
  import backtype.storm.serialization.KryoValuesDeserializer;
  import backtype.storm.serialization.KryoValuesSerializer;
  import backtype.storm.utils.Utils;
  import com.netflix.curator.framework.CuratorFramework;
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  import org.apache.zookeeper.CreateMode;
  import org.apache.zookeeper.KeeperException;
  
  public class TransactionalState {
      CuratorFramework _curator;
      KryoValuesSerializer _ser;
      KryoValuesDeserializer _des;
      
      public static TransactionalState newUserState(Map conf, String id, Map componentConf) {
          return new TransactionalState(conf, id, componentConf, "user");
      }
      
      public static TransactionalState newCoordinatorState(Map conf, String id, Map componentConf) {
          return new TransactionalState(conf, id, componentConf, "coordinator");        
      }
      
      protected TransactionalState(Map conf, String id, Map componentConf, String subroot) {
          try {
              conf = new HashMap(conf);
              // ensure that the serialization registrations are consistent with the declarations in this spout
              if(componentConf!=null) {
                  conf.put(Config.TOPOLOGY_KRYO_REGISTER,
                           componentConf
                                .get(Config.TOPOLOGY_KRYO_REGISTER));
              }
              String rootDir = conf.get(Config.TRANSACTIONAL_ZOOKEEPER_ROOT) + "/" + id + "/" + subroot;
              List<String> servers = (List<String>) getWithBackup(conf, Config.TRANSACTIONAL_ZOOKEEPER_SERVERS, Config.STORM_ZOOKEEPER_SERVERS);
              Object port = getWithBackup(conf, Config.TRANSACTIONAL_ZOOKEEPER_PORT, Config.STORM_ZOOKEEPER_PORT);
              CuratorFramework initter = Utils.newCuratorStarted(conf, servers, port);
              try {
                  initter.create().creatingParentsIfNeeded().forPath(rootDir);
              } catch(KeeperException.NodeExistsException e)  {
                  
              }
              
              initter.close();
                                      
              _curator = Utils.newCuratorStarted(conf, servers, port, rootDir);
              _ser = new KryoValuesSerializer(conf);
              _des = new KryoValuesDeserializer(conf);
          } catch (Exception e) {
             throw new RuntimeException(e);
          }
      }
      
      public void setData(String path, Object obj) {
          path = "/" + path;
          byte[] ser = _ser.serializeObject(obj);
          try {
              if(_curator.checkExists().forPath(path)!=null) {
                  _curator.setData().forPath(path, ser);
              } else {
                  _curator.create()
                          .creatingParentsIfNeeded()
                          .withMode(CreateMode.PERSISTENT)
                          .forPath(path, ser);
              }
          } catch(Exception e) {
              throw new RuntimeException(e);
          }        
      }
      
      public void delete(String path) {
          path = "/" + path;
          try {
              _curator.delete().forPath(path);
          } catch (Exception e) {
              throw new RuntimeException(e);
          }
      }
      
      public List<String> list(String path) {
          path = "/" + path;
          try {
              if(_curator.checkExists().forPath(path)==null) {
                  return new ArrayList<String>();
              } else {
                  return _curator.getChildren().forPath(path);
              }
          } catch(Exception e) {
              throw new RuntimeException(e);
          }   
      }
      
      public void mkdir(String path) {
          setData(path, 7);
      }
      
      public Object getData(String path) {
          path = "/" + path;
          try {
              if(_curator.checkExists().forPath(path)!=null) {
                  return _des.deserializeObject(_curator.getData().forPath(path));
              } else {
                  return null;
              }
          } catch(Exception e) {
              throw new RuntimeException(e);
          }
      }
      
      public void close() {
          _curator.close();
      }
      
      private Object getWithBackup(Map amap, Object primary, Object backup) {
          Object ret = amap.get(primary);
          if(ret==null) return amap.get(backup);
          return ret;
      }
  }
  