/*
    * Copyright (C) 2005-2015 Schlichtherle IT Services.
    * All rights reserved. Use is subject to license terms.
    */
   package net.java.truevfs.kernel.spec;
   
   import java.util.*;
   import javax.annotation.CheckForNull;
   import javax.annotation.concurrent.Immutable;
  import net.java.truecommons.services.Container;
  
  /**
   * An abstract composite driver.
   * This class provides an implementation of {@link #newController} which uses
   * the file system driver map returned by {@link #get()} to lookup the
   * appropriate driver for the scheme of any given mount point.
   * <p>
   * Subclasses should be immutable, too.
   *
   * @author Christian Schlichtherle
   */
  @Immutable
  public abstract class FsAbstractCompositeDriver
  implements FsCompositeDriver, Container<Map<FsScheme, FsDriver>> {
  
      @Override
      public final FsModel newModel(
              final FsManager context,
              final FsMountPoint mountPoint,
              final FsModel parent) {
          assert null == parent
                      ? null == mountPoint.getParent()
                      : parent.getMountPoint().equals(mountPoint.getParent());
          return driver(mountPoint).newModel(context, mountPoint, parent);
      }
  
      @Override
      public final FsController newController(
              final FsManager context,
              final FsModel model,
              final @CheckForNull FsController parent)
      throws ServiceConfigurationError {
          assert null == parent
                      ? null == model.getParent()
                      : parent.getModel().equals(model.getParent());
          return driver(model.getMountPoint()).newController(context, model, parent);
      }
  
      private FsDriver driver(final FsMountPoint mountPoint) {
          final FsScheme scheme = mountPoint.getScheme();
          final FsDriver driver = get().get(scheme);
          if (null == driver)
              throw new ServiceConfigurationError(scheme
                      + " (Unknown file system scheme! May be the class path doesn't contain the respective driver module or it isn't set up correctly?)");
          return driver;
      }
  }