dbconfig.java

数据挖掘的工具代码（包含fp-tree,appriory

    try
      {
	for (int i = 0; i < groups.size(); i++)
	  {
	    String group = (String)groups.get(i);
	    if (group == null)
	      throw new DBConfigException("Invalid addUser() parameters!");
	  }
      }
    catch (ClassCastException e)
      {
	throw new DBConfigException("Invalid addUser() parameters!");
      }

    // throws a DBConfigException if the user does not exist
    ID uID  = getUid(user); // initiator of the operation
    int uid1;
    ID gID;

    // check if uid belongs to admin
    check_belong_admin(uID);

    // check if the user is already installed on the system
    try 
      {
	getUid(name);
      }
    catch (DBConfigException e)
      {
	// if user belongs to admin then he must have full permissions
	for (int i = 0; i < groups.size(); i++)
	  if (groups.get(i).equals("admin"))
	    {
	      permissions = ADD_NEW_GROUPS | ADD_NEW_ALGORITHMS 
		| ADD_NEW_DATABASES;
	      break;
	    }

	// the name is not already in use
	// add the new user to the users list
	users.add(new User(uid1 = getNextUID(), name, password, permissions));

	// add the group "all" to the rest of groups
	groups.add("all");
	eliminateDuplicates(groups);

	boolean all = true;
	// add all user - group associations
	for (int i = 0; i < groups.size(); i++)
	  {
	    try
	      {
		// throws a DBConfigException if the group does not exist
		gID = getGid((String)groups.get(i));

		// add the pair uid1 - gid to the usersGroups list
		usersGroups.add(new UserGroup(uid1, gID.id));
	      }
	    catch (DBConfigException e1)
	      {
		// one of the groups is not valid
		all = false;
	      }
	  }

	// save DBConfig object to the disk
	saveDBConfig();
	    
	if (all) 
	  return;
	else
	  throw new DBConfigWarning("Not all specified groups are valid groups.");
      }

    // if this point is reached, no exception was thrown in the try above
    // newName is already in use, can not add a user with this name
    throw new DBConfigException("The user name " + name + " is already in use.");
  }

  /**
   * Deletes a user. All the resources owned by the user will be inherited
   * by the admin user.
   *
   * @exception DBConfigException   The operation can not be completed.
   * @param user   The initiator of the operation. The <code>user</code>
   * should belong to the admin group.
   * @param name   The name of the user to be deleted.
   */
  public synchronized void deleteUser(String user, String name)
    throws DBConfigException
  {
    // check arguments for validity
    if (user == null 
	|| name == null)
      throw new DBConfigException("Invalid deleteUser() parameters!");

    // throws a DBConfigException if the user does not exist
    ID uID  = getUid(user); // initiator of the operation
    ID uID1 = getUid(name); // user to be deleted

    if (uID1.id < FIRST_FREE_UID)
      throw new DBConfigException("Cannot remove " + name);

    // check if uid belong to the group admin
    // throws a DBConfigException if not
    check_belong_admin(uID);

    // if the user uID1 is logged on
    if (((User)users.get(uID1.index)).countLogged > 0)
      // schedule the user to be deleted
      ((User)users.get(uID1.index)).toBeDeleted = true;
    else
      // else, remove user
      deleteUser(uID1);
    
    // save DBConfig object to the disk
    saveDBConfig();
  }

  /**
   * Changes the name of a user.
   *
   * @exception DBConfigException   The operation can not be completed.
   * @param user   The initiator of the operation. The <code>user</code>
   * should belong to the admin group.
   * @param name   The name of the user.
   * @param newName   The new name of the user.
   */
  public synchronized void changeUserName(String user, String name, 
					  String newName)
    throws DBConfigException
  {
    // check arguments for validity
    if (user == null 
	|| name == null
	|| newName == null)
      throw new DBConfigException("Invalid changeUserName() parameters!");

    // throws a DBConfigException if the user does not exist
    ID uID  = getUid(user); // initiator of the operation
    ID uID1 = getUid(name); // user whose name will be changed

    if (uID1.id == ADMIN_UID)
      throw new DBConfigException("Cannot change name for admin.");
    if (uID1.id == ANONYMOUS_UID)
      throw new DBConfigException("Cannot change name for anonymous.");

    // if the user uID1 is logged on
    if (((User)users.get(uID1.index)).countLogged > 0)
      throw new DBConfigException("Cannot change name for a logged user.");

    // check if uid belong to the group admin
    // throws a DBConfigException if not
    check_belong_admin(uID);

    try 
      {
	getUid(newName);
      }
    catch (DBConfigException e)
      {
	// the new name is not already in use
	// change the old name to the new name
	((User)users.get(uID1.index)).name = newName;

	// save DBConfig object to the disk
	saveDBConfig();
	return;
      }

    // if this point is reached, no exception was thrown in the try above
    // newName is already in use, can not change the old name
    // to the newName
    throw new DBConfigException("User name " + newName + " is already in use.");
  }

  /**
   * Changes the password of a user.
   *
   * @exception DBConfigException   The operation can not be completed.
   * @param user   The initiator of the operation. The <code>user</code>
   * should belong to the admin group or should be the same as 
   * <code>name</code>.
   * @param name   The name of the user whose password will be changed.
   * @param newPassword   The new password.
   */
  public synchronized void changePassword(String user, String name, 
					  String newPassword)
    throws DBConfigException
  {
    // check arguments for validity
    if (user == null 
	|| name == null
	|| newPassword == null)
      throw new DBConfigException("Invalid changePassword() parameters!");

    // throws a DBConfigException if the user does not exist
    ID uID  = getUid(user); // initiator of the operation
    ID uID1 = getUid(name); // user whose password will be changed
    
    // if we are not in the case that a user wants to change its
    // own password, check if the user belongs to the admin group
    // throws a DBConfigException if the user does not belong
    if (!(user.equals(name)))
      check_belong_admin(uID);

    // change password
    ((User)users.get(uID1.index)).password = newPassword;

    // save DBConfig object to the disk
    saveDBConfig();
  }

  /**
   * Changes the permissions of a user.
   *
   * @exception DBConfigException   The operation can not be completed.
   * @param user   The initiator of the operation. The <code>user</code>
   * should belong to the admin group.
   * @param name   The name of the user whose permissions will be changed.
   * @param newPermissions   The new permissions.
   */
  public synchronized void changePermissions(String user, String name, 
					     long newPermissions)
    throws DBConfigException
  {
    // check arguments for validity
    if (user == null 
	|| name == null)
      throw new DBConfigException("Invalid changePermissions() parameters!");

    // throws a DBConfigException if the user does not exist
    ID uID  = getUid(user); // initiator of the operation
    ID uID1 = getUid(name); // user whose permissions will be changed

    if (uID1.id == ADMIN_UID)
      throw new DBConfigException("Cannot change permissions for admin.");
    if (uID1.id == ANONYMOUS_UID)
      throw new DBConfigException("Cannot change permissions for anonymous.");

    // check if uid belong to the group admin
    // throws a DBConfigException if not
    check_belong_admin(uID);

    try
      {
	check_belong_admin(uID1);
      }
    catch (DBConfigException e)
      {
	// change the permissions
	((User)users.get(uID1.index)).permissions = newPermissions;
	
	// save DBConfig object to the disk
	saveDBConfig();
	return;
      }

    // we get here if the name was an administrator
    throw new DBConfigException("Cannot change permissions for administrators.");
  }

  /**
   * Increment a user's connection count.
   *
   * @exception DBConfigException   The operation can not be completed.
   * @param user   The name of the user.
   */
  public synchronized void markLogged(String user)
    throws DBConfigException
  {
    // check arguments for validity
    if (user == null)
      throw new DBConfigException("Invalid markLogged() parameters!");

    // throws a DBConfigException if the user does not exist
    ID uID = getUid(user);

    ((User)users.get(uID.index)).countLogged++;

    // save DBConfig object to the disk
    saveDBConfig();
  }

  /**
   * Decrement a user's connection count.
   *
   * @exception DBConfigException   the operation can not be completed.
   * @param user   The name of the user.
   */
  public synchronized void unmarkLogged(String user)
    throws DBConfigException
  {
    // check arguments for validity
    if (user == null)
      throw new DBConfigException("Invalid unmarkLogged() parameters!");

    // throws a DBConfigException if the user does not exist
    ID uID = getUid(user);

    // if the user is scheduled to be deleted, delete the user
    if (((User)users.get(uID.index)).toBeDeleted)
      deleteUser(uID);
    else
      ((User)users.get(uID.index)).countLogged--;

    // save DBConfig object to the disk
    saveDBConfig();
  }

  // in the following algorithm related methods, variable name refers to
  // algorithm name.

  /**
   * Adds a new algorithm. The <code>user</code> will be the owner
   * of the algorithm.
   *
   * @exception DBConfigException   The operation can not be completed,
   * a user with the name <code>user</code> does not exist or
   * a group with the name <code>group</code> does not exist.
   * @param user   The owner of the new algorithm. This user should have
   * permissions to add new algorithms in the system.
   * @param name   The name of the algorithm.
   * @param group   The group to which the algorithm belongs.
   */
  public synchronized void addAlgorithm(String user, String name, String group)
    throws DBConfigException
  {
    // check arguments for validity
    if (user == null
	|| name == null
	|| group == null)
      throw new DBConfigException("Invalid addAlgorithm() parameters!");

    // throws a DBConfigException if the user or group do not exist
    ID uID = getUid(user);  // initiator of the operation
    ID gID = getGid(group); // the group to which the algorithm belongs
    
    // checks if the user has permissions to add a new algorithm
    // throws a DBConfigException if not
    check_perm_algorithms(uID);

    // check if the an algorithm with name already exists
    try 
      {
	getAid(name);
      }
    catch (DBConfigException e)
      {
	// the name for this algorithm is not already in use
	// add the new algorithm and return
	algorithms.add(new Algorithm(getNextAID(), name, uID.id, gID.id));

	// save DBConfig object to the disk
	saveDBConfig();
	return;
      }
    
    // if this point is reached, no exception was thrown in the try above    
    // this name of the algorithm is already in use
    // can not complete the operation
    throw new DBConfigException("The algorithm name " + name + " is already in use.");
  }

  /**
   * Deletes an algorithm.
   *
   * @exception DBConfigException   The operation can not be completed,
   * a user with the name <code>user</code> does not exist or
   * an algorithm with the name <code>name</code> does not exist.
   * @param user   The initiator of the operation. The <code>user</code> 
   * should be the owner of the algorithm or he should belong to the
   * admin group.
   * @param name   The name of the algorithm to be deleted.
   */
  public synchronized void deleteAlgorithm(String user, String name)
    throws DBConfigException
  {
    // check arguments for validity
    if (user == null
	|| name == null)
      throw new DBConfigException("Invalid deleteAlgorithm() parameters!");

    // if one of the following does not exist
    // a DBConfigException is thrown
    ID uID = getUid(user);
    ID aID = getAid(name);

    if (aID.id < FIRST_FREE_AID)
      throw new DBConfigException("Cannot remove " + name);

    // check if uid is the admin
    try 
      {
	check_belong_admin(uID);
      }
    catch (DBConfigException e)
      {
	// uid is not in admin group
	// check if it is the owner of the algorithm

	// look for aid in the list of algorithms 
	// if uid is not the owner of aid a DBConfigException 
	// is thrown
	check_owner_algorithm(uID, aID);
      }
	
    // if this point is reached uid is in admin or
    // uid is the owner of the algorithm aid

    // if algorithm is used just mark it for deletion
    if (((Algorithm)algorithms.get(aID.index)).countUsage > 0)
      {
	((Algorithm)algorithms.get(aID.index)).toBeDeleted = true;
	// save DBConfig object to the disk
	saveDBConfig();
      }
    else
      {
	// otherwise remove the algorithm from the list
	algorithms.remove(aID.index);

	// save DBConfig object to the disk
	saveDBConfig();

	try
	  {
	    File file_to_delete = new File(name + ".jar");
	    
	    if(file_to_delete.delete() ==  false)
	      System.err.println("Could not delete " + name + ".jar");
	  }
	catch (Throwable e)
	  {
	    throw new DBConfigException("Some errors occured: " + e);
	  }
      }
  }

  /**
   * Changes the group of the algorithm.
   *