fbintf/client/FBTransaction.pas

(*
 *  Firebird Interface (fbintf). The fbintf components provide a set of
 *  Pascal language bindings for the Firebird API. Although predominantly
 *  a new development they include source code taken from IBX and may be
 *  considered a derived product. This software thus also includes the copyright
 *  notice and license conditions from IBX.
 *
 *  Except for those parts dervied from IBX, contents of this file are subject
 *  to the Initial Developer's 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 here:
 *
 *    http://www.firebirdsql.org/index.php?op=doc&id=idpl
 *
 *  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 Initial Developer of the Original Code is Tony Whyman.
 *
 *  The Original Code is (C) 2016 Tony Whyman, MWA Software
 *  (http://www.mwasoftware.co.uk).
 *
 *  All Rights Reserved.
 *
 *  Contributor(s): ______________________________________.
 *
*)
{************************************************************************}
{                                                                        }
{       Borland Delphi Visual Component Library                          }
{       InterBase Express core components                                }
{                                                                        }
{       Copyright (c) 1998-2000 Inprise Corporation                      }
{                                                                        }
{    InterBase Express is based in part on the product                   }
{    Free IB Components, written by Gregory H. Deatz for                 }
{    Hoagland, Longo, Moran, Dunst & Doukas Company.                     }
{    Free IB Components is used under license.                           }
{                                                                        }
{    The contents of this file are subject to the InterBase              }
{    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.Inprise.com/IPL.html }
{    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 was created by InterBase Software Corporation     }
{       and its successors.                                              }
{    Portions created by Inprise Corporation are Copyright (C) Inprise   }
{       Corporation. All Rights Reserved.                                }
{    Contributor(s): Jeff Overcash                                       }
{                                                                        }
{    IBX For Lazarus (Firebird Express)                                  }
{    Contributor: Tony Whyman, MWA Software http://www.mwasoftware.co.uk }
{    Portions created by MWA Software are copyright McCallum Whyman      }
{    Associates Ltd 2011 - 2015                                                }
{                                                                        }
{************************************************************************}
unit FBTransaction;

{$IFDEF FPC}
{$mode objfpc}{$H+}
{$interfaces COM}
{$ENDIF}

interface

uses
  Classes, SysUtils, IB, FBParamBlock, FBActivityMonitor;

type
  { TFBTransaction }

  TFBTransaction = class(TActivityReporter, IActivityMonitor,ITransaction)
  private
    function GenerateTPB(sl: array of byte): ITPB;
  protected
    FTPB: ITPB;
    FSeqNo: integer;
    FDefaultCompletion: TTransactionAction;
    FAttachments: array of IAttachment; {Keep reference to attachment - ensures
                                          attachment cannot be freed before transaction}
    function GetActivityIntf(att: IAttachment): IActivityMonitor; virtual; abstract;
  public
    constructor Create(Attachments: array of IAttachment; Params: array of byte; DefaultCompletion: TTransactionAction); overload;
    constructor Create(Attachments: array of IAttachment; TPB: ITPB; DefaultCompletion: TTransactionAction); overload;
    constructor Create(Attachment: IAttachment; Params: array of byte; DefaultCompletion: TTransactionAction); overload;
    constructor Create(Attachment: IAttachment; TPB: ITPB; DefaultCompletion: TTransactionAction); overload;
    destructor Destroy; override;
    procedure DoDefaultTransactionEnd(Force: boolean);

  public
    {ITransaction}
    function getTPB: ITPB;
    procedure PrepareForCommit;virtual; abstract;
    procedure Commit(Force: boolean=false);  virtual; abstract;
    procedure CommitRetaining;  virtual; abstract;
    function GetInTransaction: boolean; virtual; abstract;
    function GetAttachmentCount: integer;
    function GetAttachment(index: integer): IAttachment;
    procedure Rollback(Force: boolean=false);  virtual; abstract;
    procedure RollbackRetaining;  virtual; abstract;
    procedure Start(DefaultCompletion: TTransactionCompletion=taCommit); overload; virtual; abstract;
    procedure Start(TPB: ITPB; DefaultCompletion: TTransactionCompletion=taCommit); overload;

    property InTransaction: boolean read GetInTransaction;
    property TransactionSeqNo: integer read FSeqNo;
  end;

implementation

uses FBMessages, FBStatement;

{ TFBTransaction }

function TFBTransaction.GenerateTPB(sl: array of byte): ITPB;
var
  i: Integer;
begin
  Result := TTPB.Create;
  for i := 0 to Length(sl) - 1 do
    Result.Add(sl[i]);
end;

constructor TFBTransaction.Create(Attachments: array of IAttachment;
  Params: array of byte; DefaultCompletion: TTransactionAction);
begin
  Create(Attachments,GenerateTPB(Params), DefaultCompletion);
end;

constructor TFBTransaction.Create(Attachments: array of IAttachment; TPB: ITPB;
  DefaultCompletion: TTransactionAction);
var
  i: Integer;
begin
  inherited Create(nil);
  if Length(Attachments) = 0 then
    IBError(ibxeEmptyAttachmentsList,[nil]);

  SetLength(FAttachments,Length(Attachments));
  for i := 0 to Length(Attachments) - 1 do
  begin
    AddMonitor(GetActivityIntf(Attachments[i]));
    FAttachments[i] := Attachments[i];
  end;
  FTPB := TPB;
  Start(DefaultCompletion);
end;

constructor TFBTransaction.Create(Attachment: IAttachment;
  Params: array of byte; DefaultCompletion: TTransactionAction);
begin
  Create(Attachment,GenerateTPB(Params),DefaultCompletion);
end;

constructor TFBTransaction.Create(Attachment: IAttachment; TPB: ITPB;
  DefaultCompletion: TTransactionAction);
begin
  inherited Create(nil);
  AddMonitor(GetActivityIntf(Attachment));
  SetLength(FAttachments,1);
  FAttachments[0] := Attachment;
  FTPB := TPB;
  Start(DefaultCompletion);
end;

destructor TFBTransaction.Destroy;
begin
  DoDefaultTransactionEnd(false);
  inherited Destroy;
end;

procedure TFBTransaction.DoDefaultTransactionEnd(Force: boolean);
var i: integer;
    intf: TInterfacedObject;
begin
  if InTransaction then
  begin
    for i := 0 to InterfaceCount - 1 do
    begin
      intf := GetInterface(i);
      if (intf <> nil) and  (intf is TFBStatement) then
        TFBStatement(intf).TransactionEnding(self,Force);
    end;
    case FDefaultCompletion of
    taRollback:
      Rollback(Force);
    taCommit:
      Commit(Force);
    end;
  end;
end;

function TFBTransaction.getTPB: ITPB;
begin
  Result := FTPB;
end;

function TFBTransaction.GetAttachmentCount: integer;
begin
  Result := Length(FAttachments);
end;

function TFBTransaction.GetAttachment(index: integer): IAttachment;
begin
  if (index >= 0) and (index < Length(FAttachments)) then
    Result := FAttachments[index]
  else
    IBError(ibxeAttachmentListIndexError,[index]);
end;

procedure TFBTransaction.Start(TPB: ITPB; DefaultCompletion: TTransactionCompletion
  );
begin
  FTPB := TPB;
  Start(DefaultCompletion);
end;

end.

Revision:	45
Committed:	Tue Dec 6 10:33:46 2016 UTC (7 years, 11 months ago) by tony
Content type:	text/x-pascal
File size:	8217 byte(s)
Log Message:	Committing updates for Release R2-0-0
#	User	Rev	Content
1	tony	45	(*
2			* Firebird Interface (fbintf). The fbintf components provide a set of
3			* Pascal language bindings for the Firebird API. Although predominantly
4			* a new development they include source code taken from IBX and may be
5			* considered a derived product. This software thus also includes the copyright
6			* notice and license conditions from IBX.
7			*
8			* Except for those parts dervied from IBX, contents of this file are subject
9			* to the Initial Developer's Public License Version 1.0 (the "License"); you
10			* may not use this file except in compliance with the License. You may obtain a
11			* copy of the License here:
12			*
13			* http://www.firebirdsql.org/index.php?op=doc&id=idpl
14			*
15			* Software distributed under the License is distributed on an "AS
16			* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
17			* implied. See the License for the specific language governing rights
18			* and limitations under the License.
19			*
20			* The Initial Developer of the Original Code is Tony Whyman.
21			*
22			* The Original Code is (C) 2016 Tony Whyman, MWA Software
23			* (http://www.mwasoftware.co.uk).
24			*
25			* All Rights Reserved.
26			*
27			* Contributor(s): ______________________________________.
28			*
29			*)
30			{************************************************************************}
31			{ }
32			{ Borland Delphi Visual Component Library }
33			{ InterBase Express core components }
34			{ }
35			{ Copyright (c) 1998-2000 Inprise Corporation }
36			{ }
37			{ InterBase Express is based in part on the product }
38			{ Free IB Components, written by Gregory H. Deatz for }
39			{ Hoagland, Longo, Moran, Dunst & Doukas Company. }
40			{ Free IB Components is used under license. }
41			{ }
42			{ The contents of this file are subject to the InterBase }
43			{ Public License Version 1.0 (the "License"); you may not }
44			{ use this file except in compliance with the License. You }
45			{ may obtain a copy of the License at http://www.Inprise.com/IPL.html }
46			{ Software distributed under the License is distributed on }
47			{ an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either }
48			{ express or implied. See the License for the specific language }
49			{ governing rights and limitations under the License. }
50			{ The Original Code was created by InterBase Software Corporation }
51			{ and its successors. }
52			{ Portions created by Inprise Corporation are Copyright (C) Inprise }
53			{ Corporation. All Rights Reserved. }
54			{ Contributor(s): Jeff Overcash }
55			{ }
56			{ IBX For Lazarus (Firebird Express) }
57			{ Contributor: Tony Whyman, MWA Software http://www.mwasoftware.co.uk }
58			{ Portions created by MWA Software are copyright McCallum Whyman }
59			{ Associates Ltd 2011 - 2015 }
60			{ }
61			{************************************************************************}
62			unit FBTransaction;
63
64			{$IFDEF FPC}
65			{$mode objfpc}{$H+}
66			{$interfaces COM}
67			{$ENDIF}
68
69			interface
70
71			uses
72			Classes, SysUtils, IB, FBParamBlock, FBActivityMonitor;
73
74			type
75			{ TFBTransaction }
76
77			TFBTransaction = class(TActivityReporter, IActivityMonitor,ITransaction)
78			private
79			function GenerateTPB(sl: array of byte): ITPB;
80			protected
81			FTPB: ITPB;
82			FSeqNo: integer;
83			FDefaultCompletion: TTransactionAction;
84			FAttachments: array of IAttachment; {Keep reference to attachment - ensures
85			attachment cannot be freed before transaction}
86			function GetActivityIntf(att: IAttachment): IActivityMonitor; virtual; abstract;
87			public
88			constructor Create(Attachments: array of IAttachment; Params: array of byte; DefaultCompletion: TTransactionAction); overload;
89			constructor Create(Attachments: array of IAttachment; TPB: ITPB; DefaultCompletion: TTransactionAction); overload;
90			constructor Create(Attachment: IAttachment; Params: array of byte; DefaultCompletion: TTransactionAction); overload;
91			constructor Create(Attachment: IAttachment; TPB: ITPB; DefaultCompletion: TTransactionAction); overload;
92			destructor Destroy; override;
93			procedure DoDefaultTransactionEnd(Force: boolean);
94
95			public
96			{ITransaction}
97			function getTPB: ITPB;
98			procedure PrepareForCommit;virtual; abstract;
99			procedure Commit(Force: boolean=false); virtual; abstract;
100			procedure CommitRetaining; virtual; abstract;
101			function GetInTransaction: boolean; virtual; abstract;
102			function GetAttachmentCount: integer;
103			function GetAttachment(index: integer): IAttachment;
104			procedure Rollback(Force: boolean=false); virtual; abstract;
105			procedure RollbackRetaining; virtual; abstract;
106			procedure Start(DefaultCompletion: TTransactionCompletion=taCommit); overload; virtual; abstract;
107			procedure Start(TPB: ITPB; DefaultCompletion: TTransactionCompletion=taCommit); overload;
108
109			property InTransaction: boolean read GetInTransaction;
110			property TransactionSeqNo: integer read FSeqNo;
111			end;
112
113			implementation
114
115			uses FBMessages, FBStatement;
116
117			{ TFBTransaction }
118
119			function TFBTransaction.GenerateTPB(sl: array of byte): ITPB;
120			var
121			i: Integer;
122			begin
123			Result := TTPB.Create;
124			for i := 0 to Length(sl) - 1 do
125			Result.Add(sl[i]);
126			end;
127
128			constructor TFBTransaction.Create(Attachments: array of IAttachment;
129			Params: array of byte; DefaultCompletion: TTransactionAction);
130			begin
131			Create(Attachments,GenerateTPB(Params), DefaultCompletion);
132			end;
133
134			constructor TFBTransaction.Create(Attachments: array of IAttachment; TPB: ITPB;
135			DefaultCompletion: TTransactionAction);
136			var
137			i: Integer;
138			begin
139			inherited Create(nil);
140			if Length(Attachments) = 0 then
141			IBError(ibxeEmptyAttachmentsList,[nil]);
142
143			SetLength(FAttachments,Length(Attachments));
144			for i := 0 to Length(Attachments) - 1 do
145			begin
146			AddMonitor(GetActivityIntf(Attachments[i]));
147			FAttachments[i] := Attachments[i];
148			end;
149			FTPB := TPB;
150			Start(DefaultCompletion);
151			end;
152
153			constructor TFBTransaction.Create(Attachment: IAttachment;
154			Params: array of byte; DefaultCompletion: TTransactionAction);
155			begin
156			Create(Attachment,GenerateTPB(Params),DefaultCompletion);
157			end;
158
159			constructor TFBTransaction.Create(Attachment: IAttachment; TPB: ITPB;
160			DefaultCompletion: TTransactionAction);
161			begin
162			inherited Create(nil);
163			AddMonitor(GetActivityIntf(Attachment));
164			SetLength(FAttachments,1);
165			FAttachments[0] := Attachment;
166			FTPB := TPB;
167			Start(DefaultCompletion);
168			end;
169
170			destructor TFBTransaction.Destroy;
171			begin
172			DoDefaultTransactionEnd(false);
173			inherited Destroy;
174			end;
175
176			procedure TFBTransaction.DoDefaultTransactionEnd(Force: boolean);
177			var i: integer;
178			intf: TInterfacedObject;
179			begin
180			if InTransaction then
181			begin
182			for i := 0 to InterfaceCount - 1 do
183			begin
184			intf := GetInterface(i);
185			if (intf <> nil) and (intf is TFBStatement) then
186			TFBStatement(intf).TransactionEnding(self,Force);
187			end;
188			case FDefaultCompletion of
189			taRollback:
190			Rollback(Force);
191			taCommit:
192			Commit(Force);
193			end;
194			end;
195			end;
196
197			function TFBTransaction.getTPB: ITPB;
198			begin
199			Result := FTPB;
200			end;
201
202			function TFBTransaction.GetAttachmentCount: integer;
203			begin
204			Result := Length(FAttachments);
205			end;
206
207			function TFBTransaction.GetAttachment(index: integer): IAttachment;
208			begin
209			if (index >= 0) and (index < Length(FAttachments)) then
210			Result := FAttachments[index]
211			else
212			IBError(ibxeAttachmentListIndexError,[index]);
213			end;
214
215			procedure TFBTransaction.Start(TPB: ITPB; DefaultCompletion: TTransactionCompletion
216			);
217			begin
218			FTPB := TPB;
219			Start(DefaultCompletion);
220			end;
221
222			end.
223