0.34b/DataAccess/ConnectionManager.pas

unit ConnectionManager;
interface

uses TypeDefs, DataAccess, Access_OniArchive, Access_OUP_ADB;

type
  TConnections = array of TDataAccess;

  TConnectionListChangedEvent = procedure of object;

  
  TConnectionManager = class
  private
    FConnections: TConnections;
    FLastID:      Integer;
    FConnectionListChanged: TConnectionListChangedEvent;
    function GetConnectionCount: Integer;
    function GetConnection(ConnectionID: Integer): TDataAccess;
    function GetConnectionByIndex(Index: Integer): TDataAccess;
    function GetConnectionIndex(ConnectionID: Integer): Integer;
    procedure RemoveConnection(ArrayIndex: Integer);
  protected
  public
    property Count: Integer read GetConnectionCount;
    property Connection[ConnectionID: Integer]: TDataAccess read GetConnection;
    property ConnectionByIndex[Index: Integer]: TDataAccess read GetConnectionByIndex;
    property ConnectionIndexByID[ConnectionID: Integer]: Integer read GetConnectionIndex;
    property OnCoonnectionListChanged: TConnectionListChangedEvent read FConnectionListChanged write FConnectionListChanged;

    constructor Create;
    function Close: Boolean;

    function OpenConnection(FileName: String; var Msg: TStatusMessages): Integer;
    function CloseConnectionByIndex(Index: Integer; var Msg: TStatusMessages): Boolean; overload;
    function CloseConnection(ID: Integer; var Msg: TStatusMessages): Boolean; overload;
    function CloseConnection(FileName: String; var Msg: TStatusMessages): Boolean; overload;
    function FileOpened(FileName: String): Integer;
  published
  end;


var
  ConManager: TConnectionManager;


implementation
uses
  SysUtils, Dialogs;

(*
 Implementation of TConnectionManager
*)


function TConnectionManager.GetConnectionCount: Integer;
begin
  Result := Length(FConnections);
end;

function TConnectionManager.GetConnectionIndex(ConnectionID: Integer): Integer;
var
  i: Integer;
begin
  Result := -1;
  if Count > 0 then
    for i := 0 to Count - 1 do
      if ConnectionByIndex[i].ConnectionID = ConnectionID then
      begin
        Result := i;
        Break;
      end;
end;

function TConnectionManager.GetConnection(ConnectionID: Integer): TDataAccess;
var
  i: Integer;
begin
  Result := nil;
  if Length(FConnections) > 0 then
  begin
    for i := 0 to High(FConnections) do
    begin
      if FConnections[i].ConnectionID = ConnectionID then
      begin
        Result := FConnections[i];
        Break;
      end;
    end;
    if i = Length(FConnections) then
      ShowMessage('Couldn''t find specified ConnectionID (' +
          IntToStr(ConnectionID) + '). Please contact developer!!!');
  end;
end;


function TConnectionManager.GetConnectionByIndex(Index: Integer): TDataAccess;
begin
  Result := nil;
  if index < Length(FConnections) then
  begin
    Result := FConnections[index];
  end;
end;

constructor TConnectionManager.Create;
begin
  inherited;
  FLastID := 0;
end;

function TConnectionManager.Close: Boolean;
begin
  Result := False;
  if Length(FConnections) > 0 then
    Exit;

  inherited;
end;


function TConnectionManager.OpenConnection(FileName: String; var Msg: TStatusMessages): Integer;
var
  i: Integer;
  ext: String;
  backend: TDataBackend;
  CreateMsg: TStatusMessages;
begin
  Msg := SM_UnknownError;
  Result := -1;

  if Length(FConnections) > 0 then
  begin
    for i := 0 to High(FConnections) do
    begin
      if FConnections[i].FileName = FileName then
      begin
        Result := FConnections[i].ConnectionID;
        Msg := SM_AlreadyOpened;
        Exit;
      end;
    end;
  end;

  if not FileExists(FileName) then
  begin
    Msg := SM_FileNotFound;
    Exit;
  end;

  ext := UpperCase(ExtractFileExt(FileName));

  if ext = '.OLDB' then
    backend := DB_ADB
  else if ext = '.DAT' then
    backend := DB_ONI
  else
  begin
    Msg := SM_UnknownExtension;
    Exit;
  end;

  SetLength(FConnections, Length(FConnections) + 1);
  i := High(FConnections);
  case backend of
    DB_ONI:
      FConnections[i] := TAccess_OniArchive.Create(FileName, FLastID + 1, CreateMsg);
    DB_ADB:
      FConnections[i] := TAccess_OUP_ADB.Create(FileName, FLastID + 1, CreateMsg);
  end;

  if CreateMsg = SM_OK then
  begin
    FLastID := FConnections[i].ConnectionID;
    Result := FLastID;
    Msg := SM_OK;
  end
  else
  begin
    FConnections[i].Close;
    FConnections[i].Free;
    FConnections[i] := nil;
    SetLength(FConnections, Length(FConnections) - 1);
    Msg := CreateMsg;
  end;
end;


procedure TConnectionManager.RemoveConnection(ArrayIndex: Integer);
var
  i: Integer;
begin
  if Length(FConnections) > 1 then
  begin
    for i := ArrayIndex to High(FConnections) - 1 do
    begin
      FConnections[i] := FConnections[i + 1];
    end;
  end;
  SetLength(FConnections, Length(FConnections) - 1);
end;

function TConnectionManager.CloseConnectionByIndex(Index: Integer; var Msg: TStatusMessages): Boolean;
begin
  Msg := SM_UnknownError;
  Result := False;

  if Index < Length(FConnections) then
  begin
    FConnections[Index].Close;
    RemoveConnection(Index);
    Msg := SM_OK;
    Result := True;
  end;
end;

function TConnectionManager.CloseConnection(ID: Integer; var Msg: TStatusMessages): Boolean;
var
  i: Integer;
begin
  Msg := SM_UnknownError;
  Result := False;

  if Length(FConnections) > 0 then
  begin
    for i := 0 to High(FConnections) do
    begin
      if FConnections[i].ConnectionID = ID then
      begin
        FConnections[i].Close;
        RemoveConnection(i);
        Msg := SM_OK;
        Result := True;
        Exit;
      end;
    end;
  end;
end;

function TConnectionManager.CloseConnection(FileName: String; var Msg: TStatusMessages): Boolean;
var
  i: Integer;
begin
  Msg := SM_UnknownError;
  Result := False;

  if Length(FConnections) > 0 then
  begin
    for i := 0 to High(FConnections) do
    begin
      if FConnections[i].FileName = FileName then
      begin
        FConnections[i].Close;
        RemoveConnection(i);
        Msg := SM_OK;
        Result := True;
        Exit;
      end;
    end;
  end;
end;


function TConnectionManager.FileOpened(FileName: String): Integer;
var
  i: Integer;
begin
  Result := -1;
  if Length(FConnections) > 0 then
    for i := 0 to High(FConnections) do
      if FConnections[i].FileName = FileName then
      begin
        Result := FConnections[i].ConnectionID;
        Exit;
      end;
end;


initialization
  ConManager := TConnectionManager.Create;
finalization
  ConManager.Free;
end.
Revision:	205
Committed:	Sun May 27 20:07:55 2007 UTC (18 years, 4 months ago) by alloc
Content type:	text/x-pascal
File size:	6770 byte(s)
Log Message:
#	Content
1	unit ConnectionManager;
2	interface
3
4	uses TypeDefs, DataAccess, Access_OniArchive, Access_OUP_ADB;
5
6	type
7	TConnections = array of TDataAccess;
8
9	TConnectionListChangedEvent = procedure of object;
10
11
12	TConnectionManager = class
13	private
14	FConnections: TConnections;
15	FLastID: Integer;
16	FConnectionListChanged: TConnectionListChangedEvent;
17	function GetConnectionCount: Integer;
18	function GetConnection(ConnectionID: Integer): TDataAccess;
19	function GetConnectionByIndex(Index: Integer): TDataAccess;
20	function GetConnectionIndex(ConnectionID: Integer): Integer;
21	procedure RemoveConnection(ArrayIndex: Integer);
22	protected
23	public
24	property Count: Integer read GetConnectionCount;
25	property Connection[ConnectionID: Integer]: TDataAccess read GetConnection;
26	property ConnectionByIndex[Index: Integer]: TDataAccess read GetConnectionByIndex;
27	property ConnectionIndexByID[ConnectionID: Integer]: Integer read GetConnectionIndex;
28	property OnCoonnectionListChanged: TConnectionListChangedEvent read FConnectionListChanged write FConnectionListChanged;
29
30	constructor Create;
31	function Close: Boolean;
32
33	function OpenConnection(FileName: String; var Msg: TStatusMessages): Integer;
34	function CloseConnectionByIndex(Index: Integer; var Msg: TStatusMessages): Boolean; overload;
35	function CloseConnection(ID: Integer; var Msg: TStatusMessages): Boolean; overload;
36	function CloseConnection(FileName: String; var Msg: TStatusMessages): Boolean; overload;
37	function FileOpened(FileName: String): Integer;
38	published
39	end;
40
41
42	var
43	ConManager: TConnectionManager;
44
45
46	implementation
47	uses
48	SysUtils, Dialogs;
49
50	(*
51	Implementation of TConnectionManager
52	*)
53
54
55	function TConnectionManager.GetConnectionCount: Integer;
56	begin
57	Result := Length(FConnections);
58	end;
59
60	function TConnectionManager.GetConnectionIndex(ConnectionID: Integer): Integer;
61	var
62	i: Integer;
63	begin
64	Result := -1;
65	if Count > 0 then
66	for i := 0 to Count - 1 do
67	if ConnectionByIndex[i].ConnectionID = ConnectionID then
68	begin
69	Result := i;
70	Break;
71	end;
72	end;
73
74	function TConnectionManager.GetConnection(ConnectionID: Integer): TDataAccess;
75	var
76	i: Integer;
77	begin
78	Result := nil;
79	if Length(FConnections) > 0 then
80	begin
81	for i := 0 to High(FConnections) do
82	begin
83	if FConnections[i].ConnectionID = ConnectionID then
84	begin
85	Result := FConnections[i];
86	Break;
87	end;
88	end;
89	if i = Length(FConnections) then
90	ShowMessage('Couldn''t find specified ConnectionID (' +
91	IntToStr(ConnectionID) + '). Please contact developer!!!');
92	end;
93	end;
94
95
96	function TConnectionManager.GetConnectionByIndex(Index: Integer): TDataAccess;
97	begin
98	Result := nil;
99	if index < Length(FConnections) then
100	begin
101	Result := FConnections[index];
102	end;
103	end;
104
105	constructor TConnectionManager.Create;
106	begin
107	inherited;
108	FLastID := 0;
109	end;
110
111	function TConnectionManager.Close: Boolean;
112	begin
113	Result := False;
114	if Length(FConnections) > 0 then
115	Exit;
116
117	inherited;
118	end;
119
120
121
122	function TConnectionManager.OpenConnection(FileName: String; var Msg: TStatusMessages): Integer;
123	var
124	i: Integer;
125	ext: String;
126	backend: TDataBackend;
127	CreateMsg: TStatusMessages;
128	begin
129	Msg := SM_UnknownError;
130	Result := -1;
131
132	if Length(FConnections) > 0 then
133	begin
134	for i := 0 to High(FConnections) do
135	begin
136	if FConnections[i].FileName = FileName then
137	begin
138	Result := FConnections[i].ConnectionID;
139	Msg := SM_AlreadyOpened;
140	Exit;
141	end;
142	end;
143	end;
144
145	if not FileExists(FileName) then
146	begin
147	Msg := SM_FileNotFound;
148	Exit;
149	end;
150
151	ext := UpperCase(ExtractFileExt(FileName));
152
153	if ext = '.OLDB' then
154	backend := DB_ADB
155	else if ext = '.DAT' then
156	backend := DB_ONI
157	else
158	begin
159	Msg := SM_UnknownExtension;
160	Exit;
161	end;
162
163	SetLength(FConnections, Length(FConnections) + 1);
164	i := High(FConnections);
165	case backend of
166	DB_ONI:
167	FConnections[i] := TAccess_OniArchive.Create(FileName, FLastID + 1, CreateMsg);
168	DB_ADB:
169	FConnections[i] := TAccess_OUP_ADB.Create(FileName, FLastID + 1, CreateMsg);
170	end;
171
172	if CreateMsg = SM_OK then
173	begin
174	FLastID := FConnections[i].ConnectionID;
175	Result := FLastID;
176	Msg := SM_OK;
177	end
178	else
179	begin
180	FConnections[i].Close;
181	FConnections[i].Free;
182	FConnections[i] := nil;
183	SetLength(FConnections, Length(FConnections) - 1);
184	Msg := CreateMsg;
185	end;
186	end;
187
188
189	procedure TConnectionManager.RemoveConnection(ArrayIndex: Integer);
190	var
191	i: Integer;
192	begin
193	if Length(FConnections) > 1 then
194	begin
195	for i := ArrayIndex to High(FConnections) - 1 do
196	begin
197	FConnections[i] := FConnections[i + 1];
198	end;
199	end;
200	SetLength(FConnections, Length(FConnections) - 1);
201	end;
202
203	function TConnectionManager.CloseConnectionByIndex(Index: Integer; var Msg: TStatusMessages): Boolean;
204	begin
205	Msg := SM_UnknownError;
206	Result := False;
207
208	if Index < Length(FConnections) then
209	begin
210	FConnections[Index].Close;
211	RemoveConnection(Index);
212	Msg := SM_OK;
213	Result := True;
214	end;
215	end;
216
217	function TConnectionManager.CloseConnection(ID: Integer; var Msg: TStatusMessages): Boolean;
218	var
219	i: Integer;
220	begin
221	Msg := SM_UnknownError;
222	Result := False;
223
224	if Length(FConnections) > 0 then
225	begin
226	for i := 0 to High(FConnections) do
227	begin
228	if FConnections[i].ConnectionID = ID then
229	begin
230	FConnections[i].Close;
231	RemoveConnection(i);
232	Msg := SM_OK;
233	Result := True;
234	Exit;
235	end;
236	end;
237	end;
238	end;
239
240	function TConnectionManager.CloseConnection(FileName: String; var Msg: TStatusMessages): Boolean;
241	var
242	i: Integer;
243	begin
244	Msg := SM_UnknownError;
245	Result := False;
246
247	if Length(FConnections) > 0 then
248	begin
249	for i := 0 to High(FConnections) do
250	begin
251	if FConnections[i].FileName = FileName then
252	begin
253	FConnections[i].Close;
254	RemoveConnection(i);
255	Msg := SM_OK;
256	Result := True;
257	Exit;
258	end;
259	end;
260	end;
261	end;
262
263
264	function TConnectionManager.FileOpened(FileName: String): Integer;
265	var
266	i: Integer;
267	begin
268	Result := -1;
269	if Length(FConnections) > 0 then
270	for i := 0 to High(FConnections) do
271	if FConnections[i].FileName = FileName then
272	begin
273	Result := FConnections[i].ConnectionID;
274	Exit;
275	end;
276	end;
277
278
279	initialization
280	ConManager := TConnectionManager.Create;
281	finalization
282	ConManager.Free;
283	end.