mirror of
https://github.com/mozilla/gecko-dev.git
synced 2024-11-05 08:35:26 +00:00
147 lines
6.2 KiB
C++
147 lines
6.2 KiB
C++
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
|
|
/* ***** BEGIN LICENSE BLOCK *****
|
|
* Version: NPL 1.1/GPL 2.0/LGPL 2.1
|
|
*
|
|
* The contents of this file are subject to the Netscape Public License
|
|
* Version 1.1 (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/NPL/
|
|
*
|
|
* 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 mozilla.org code.
|
|
*
|
|
* The Initial Developer of the Original Code is
|
|
* Netscape Communications Corporation.
|
|
* Portions created by the Initial Developer are Copyright (C) 1999
|
|
* the Initial Developer. All Rights Reserved.
|
|
*
|
|
* Contributor(s):
|
|
*
|
|
* Alternatively, the contents of this file may be used under the terms of
|
|
* either the GNU General Public License Version 2 or later (the "GPL"), or
|
|
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
|
|
* in which case the provisions of the GPL or the LGPL are applicable instead
|
|
* of those above. If you wish to allow use of your version of this file only
|
|
* under the terms of either the GPL or the LGPL, and not to allow others to
|
|
* use your version of this file under the terms of the NPL, indicate your
|
|
* decision by deleting the provisions above and replace them with the notice
|
|
* and other provisions required by the GPL or the LGPL. If you do not delete
|
|
* the provisions above, a recipient may use your version of this file under
|
|
* the terms of any one of the NPL, the GPL or the LGPL.
|
|
*
|
|
* ***** END LICENSE BLOCK ***** */
|
|
|
|
#include "nsMsgSearchCore.h"
|
|
|
|
#ifndef __nsMsgSearchBoolExpression_h
|
|
#define __nsMsgSearchBoolExpression_h
|
|
|
|
//-----------------------------------------------------------------------------
|
|
// nsMsgSearchBoolExpression is a class added to provide AND/OR terms in search queries.
|
|
// A nsMsgSearchBoolExpression contains either a search term or two nsMsgSearchBoolExpressions and
|
|
// a boolean operator.
|
|
// I (mscott) am placing it here for now....
|
|
//-----------------------------------------------------------------------------
|
|
|
|
/* CBoolExpression --> encapsulates one or more search terms by internally
|
|
representing the search terms and their boolean operators as a binary
|
|
expression tree. Each node in the tree consists of either
|
|
(1) a boolean operator and two nsMsgSearchBoolExpressions or
|
|
(2) if the node is a leaf node then it contains a search term.
|
|
With each search term that is part of the expression we also keep
|
|
track of either an evaluation value (XP_BOOL) or a character string.
|
|
Evaluation values are used for offline searching. The character
|
|
string is used to store the IMAP/NNTP encoding of the search term. This
|
|
makes evaluating the expression (for offline) or generating a search
|
|
encoding (for online) easier.
|
|
|
|
For IMAP/NNTP: nsMsgSearchBoolExpression has/assumes knowledge about how
|
|
AND and OR search terms are combined according to IMAP4 and NNTP protocol.
|
|
That is the only piece of IMAP/NNTP knowledge it is aware of.
|
|
|
|
Order of Evaluation: Okay, the way in which the boolean expression tree
|
|
is put together directly effects the order of evaluation. We currently
|
|
support left to right evaluation.
|
|
Supporting other order of evaluations involves adding new internal add
|
|
term methods.
|
|
*/
|
|
|
|
class nsMsgSearchBoolExpression
|
|
{
|
|
public:
|
|
|
|
// create a leaf node expression
|
|
nsMsgSearchBoolExpression(nsIMsgSearchTerm * newTerm,
|
|
PRBool EvaluationValue = PR_TRUE,
|
|
char * encodingStr = NULL);
|
|
nsMsgSearchBoolExpression(nsIMsgSearchTerm * newTerm, char * encodingStr);
|
|
|
|
// create a non-leaf node expression containing 2 expressions
|
|
// and a boolean operator
|
|
nsMsgSearchBoolExpression(nsMsgSearchBoolExpression *,
|
|
nsMsgSearchBoolExpression *,
|
|
nsMsgSearchBooleanOperator boolOp);
|
|
|
|
nsMsgSearchBoolExpression();
|
|
~nsMsgSearchBoolExpression(); // recursively destroys all sub
|
|
// expressions as well
|
|
|
|
// accesors
|
|
|
|
// Offline
|
|
nsMsgSearchBoolExpression * AddSearchTerm (nsIMsgSearchTerm * newTerm,
|
|
PRBool EvaluationValue = PR_TRUE);
|
|
nsMsgSearchBoolExpression * AddSearchTerm (nsIMsgSearchTerm * newTerm,
|
|
char * encodingStr); // IMAP/NNTP
|
|
|
|
// parses the expression tree and all
|
|
// expressions underneath this node using
|
|
// each EvaluationValue at each leaf to
|
|
// determine if the end result is PR_TRUE or PR_FALSE.
|
|
PRBool OfflineEvaluate();
|
|
|
|
// assuming the expression is for online
|
|
// searches, determine the length of the
|
|
// resulting IMAP/NNTP encoding string
|
|
PRInt32 CalcEncodeStrSize();
|
|
|
|
// fills pre-allocated
|
|
// memory in buffer with
|
|
// the IMAP/NNTP encoding for the expression
|
|
void GenerateEncodeStr(nsCString * buffer);
|
|
protected:
|
|
// if we are a leaf node, all we have is a search term
|
|
// and a Evaluation value for that search term
|
|
|
|
nsIMsgSearchTerm * m_term;
|
|
PRBool m_evalValue;
|
|
|
|
// store IMAP/NNTP encoding for the search term if applicable
|
|
nsCString m_encodingStr;
|
|
|
|
// if we are not a leaf node, then we have two other expressions
|
|
// and a boolean operator
|
|
nsMsgSearchBoolExpression * m_leftChild;
|
|
nsMsgSearchBoolExpression * m_rightChild;
|
|
nsMsgSearchBooleanOperator m_boolOp;
|
|
|
|
|
|
// internal methods
|
|
|
|
// the idea is to separate the public interface for adding terms to
|
|
// the expression tree from the order of evaluation which influences
|
|
// how we internally construct the tree. Right now, we are supporting
|
|
// left to right evaluation so the tree is constructed to represent
|
|
// that by calling leftToRightAddTerm. If future forms of evaluation
|
|
// need to be supported, add new methods here for proper tree construction.
|
|
nsMsgSearchBoolExpression * leftToRightAddTerm(nsIMsgSearchTerm * newTerm,
|
|
PRBool EvaluationValue,
|
|
char * encodingStr);
|
|
};
|
|
|
|
#endif
|