package org.apache.torque;
   
   /*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you 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.
   */
  
  import org.apache.torque.adapter.DB;
  import org.apache.torque.dsfactory.DataSourceFactory;
  import org.apache.torque.map.DatabaseMap;
  import org.apache.torque.oid.IDBroker;
  import org.apache.torque.oid.IdGenerator;
  
  /***
   * Bundles all information about a database. This includes the database adapter,
   * the database Map and the Data Source Factory.
   */
  public class Database
  {
      /***
       * The name of the database. Must be the same as the key in Torque's
       * databaseMap.
       */
      private String name;
  
      /***
       * The Database adapter which encapsulates database-specific peculiarities.
       */
      private DB adapter;
  
      /***
       * the Map of this database.
       */
      private DatabaseMap databaseMap;
  
      /***
       * The DataSourceFactory to optain connections to this database.
       */
      private DataSourceFactory dataSourceFactory;
  
      /***
       * Creates a new Database with the given name.
       *
       * @param aName the name of the database, not null.
       */
      Database(String aName)
      {
          this.name = aName;
      }
  
      /***
       * returns the name of the database.
       *
       * @return the name of the database. May be null.
       */
      public String getName()
      {
          return name;
      }
  
      /***
       * Returns the adapther to this database.
       *
       * @return the adapter to this database, or null if no adapter is set.
       */
      public DB getAdapter()
      {
          return adapter;
      }
  
      /***
       * Sets the adapter for this database.
       *
       * @param anAdapter The adapter for this database, or null to remove the
       *        current adapter from this database.
       */
      public void setAdapter(DB anAdapter)
      {
          this.adapter = anAdapter;
      }
  
      /***
       * Returns the database map for this database.
       * If the database map does not exist yet, it is created by this method.
       */
     public synchronized DatabaseMap getDatabaseMap()
     {
         if (databaseMap == null)
         {
             databaseMap = new DatabaseMap(name);
         }
         return databaseMap;
     }
 
     /***
      * Returns the DataSourceFactory for this database.
      * The DataSourceFactory is responsible to create connections
      * to this database.
      *
      * @return the DataSourceFactory for this database, or null if no
      *         DataSourceFactory exists for this database.
      */
     public DataSourceFactory getDataSourceFactory()
     {
         return dataSourceFactory;
     }
 
     /***
      * Sets the DataSourceFactory for this database.
      * The DataSourceFactory is responsible to create connections
      * to this database.
      *
      * @param aDataSourceFactory The new DataSorceFactory for this database,
      *        or null to remove the current DataSourceFactory.
      */
     public void setDataSourceFactory(DataSourceFactory aDataSourceFactory)
     {
         this.dataSourceFactory = aDataSourceFactory;
     }
 
     /***
      * Get the IDBroker for this database.
      *
      * @return The IDBroker for this database, or null if no IdBroker has
      *         been started for this database.
      */
     public IDBroker getIDBroker()
     {
         if (databaseMap == null)
         {
             return null;
         }
         return databaseMap.getIDBroker();
     }
 
     /***
      * Creates the IDBroker for this DatabaseMap and starts it for the
      * given database.
      * The information about the IdTable is stored in the databaseMap.
      * If an IDBroker already exists for the DatabaseMap, the method
      * does nothing.
      *
      * @return true if a new IDBroker was created, false otherwise.
      */
     public synchronized boolean startIDBroker()
     {
         DatabaseMap dbMap = getDatabaseMap();
         if (dbMap.getIDBroker() != null)
         {
             return false;
         }
         return dbMap.startIdBroker();
     }
 
     /***
      * Returns the IdGenerator of the given type for this Database.
      * @param type The type (i.e.name) of the IdGenerator
      * @return The IdGenerator of the requested type, or null if no IdGenerator
      *         exists for the requested type.
      */
     public IdGenerator getIdGenerator(String type)
     {
         if (databaseMap == null)
         {
             return null;
         }
         return databaseMap.getIdGenerator(type);
     }
 
     /***
      * Adds an IdGenerator to the database.
      * @param type The type of the IdGenerator
      * @param idGen The new IdGenerator for the type, or null
      *        to remove the IdGenerator of the given type.
      */
     public void addIdGenerator(String type, IdGenerator idGen)
     {
         getDatabaseMap().addIdGenerator(type, idGen);
     }
 
     /***
      * Returns the database schema for this Database.
      * @return the database schema for this database, or null if no schema
      *         has been set.
      */
     public String getSchema()
     {
         DataSourceFactory dsf = getDataSourceFactory();
         if (dsf == null)
         {
             return null;
         }
         return dsf.getSchema();
     }
 
     /***
      * Sets the schema for this database.
      * @param schema the name of the database schema to set, or null to remove
      *        the current schema.
      * @throws NullPointerException if no DatasourceFactory exists for this
      *         database.
      */
     public void setSchema(String schema)
     {
         getDataSourceFactory().setSchema(schema);
     }
 }