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
#	Content
1	(*
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