pjs/grendel/storage/mdb/nsIMdbEnv.java

81 строка
3.6 KiB
Java

/* -*- Mode: java; indent-tabs-mode: nil; c-basic-offset: 2 -*-
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.0 (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.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
* the License for the specific language governing rights and limitations
* under the License.
*
* The Original Code is the Grendel mail/news client.
*
* The Initial Developer of the Original Code is Netscape Communications
* Corporation. Portions created by Netscape are Copyright (C) 1997
* Netscape Communications Corporation. All Rights Reserved.
*
* Created: Mauro Botelho <mabotelh@email.com>, 20 Mar 1999.
*/
package grendel.storage.mdb;
/** nsIMdbEnv: a context parameter used when calling most abstract db methods.
** The main purpose of such an object is to permit a database implementation
** to avoid the use of globals to share information between various parts of
** the implementation behind the abstract db interface. An environment acts
** like a session object for a given calling thread, and callers should use
** at least one different nsIMdbEnv instance for each thread calling the API.
** While the database implementation might not be threaded, it is highly
** desirable that the db be thread-safe if calling threads use distinct
** instances of nsIMdbEnv. Callers can stop at one nsIMdbEnv per thread, or they
** might decide to make on nsIMdbEnv instance for every nsIMdbPort opened, so that
** error information is segregated by database instance. Callers create
** instances of nsIMdbEnv by calling the MakeEnv() method in nsIMdbFactory.
**
** tracing: an environment might support some kind of tracing, and this
** boolean attribute permits such activity to be enabled or disabled.
**
** errors: when a call to the abstract db interface returns, a caller might
** check the number of outstanding errors to see whether the operation did
** actually succeed. Each nsIMdbEnv should have all its errors cleared by a
** call to ClearErrors() before making each call to the abstract db API,
** because outstanding errors might disable further database actions. (This
** is not done inside the db interface, because the db cannot in general know
** when a call originates from inside or outside -- only the app knows this.)
**
** error hook: callers can install an instance of nsIMdbErrorHook to receive
** error notifications whenever the error count increases. The hook can
** be uninstalled by passing a null pointer.
**
*/
public interface nsIMdbEnv extends nsIMdbObject { // db specific context parameter
// { ===== begin nsIMdbEnv methods =====
// { ----- begin attribute methods -----
int GetErrorCount(int outCount, boolean outShouldAbort);
int GetWarningCount(int outCount, boolean outShouldAbort);
int GetDoTrace(boolean outDoTrace);
int SetDoTrace(boolean inDoTrace);
boolean GetAutoClear();
void SetAutoClear(boolean inAutoClear);
nsIMdbErrorHook GetErrorHook();
void SetErrorHook(nsIMdbErrorHook ioErrorHook); // becomes referenced
//virtual mdb_err GetHeap(nsIMdbHeap** acqHeap) = 0;
//virtual mdb_err SetHeap(
//nsIMdbHeap* ioHeap) = 0; // becomes referenced
// } ----- end attribute methods -----
int ClearErrors(); // clear errors beore re-entering db API
int ClearWarnings(); // clear warnings
int ClearErrorsAndWarnings(); // clear both errors & warnings
// } ===== end nsIMdbEnv methods =====
};