ModifiableDatabaseSchemaImpl


1   /*
2    * Copyright (c) 2003 - 2007 OpenSubsystems s.r.o. Slovak Republic. All rights reserved.
3    * 
4    * Project: OpenSubsystems
5    * 
6    * $Id: ModifiableDatabaseSchemaImpl.java,v 1.1 2007/01/10 05:09:38 bastafidli Exp $
7    * 
8    * This program is free software; you can redistribute it and/or modify
9    * it under the terms of the GNU General Public License as published by
10   * the Free Software Foundation; version 2 of the License. 
11   * 
12   * This program is distributed in the hope that it will be useful,
13   * but WITHOUT ANY WARRANTY; without even the implied warranty of
14   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15   * GNU General Public License for more details.
16   * 
17   * You should have received a copy of the GNU General Public License
18   * along with this program; if not, write to the Free Software
19   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
20   */
21  
22  package org.opensubsystems.core.persist.db;
23  
24  import java.sql.Connection  ;
25  import java.sql.SQLException  ;
26  import java.util.HashMap  ;
27  import java.util.Map  ;
28  
29  import org.opensubsystems.core.data.DataConstant;
30  import org.opensubsystems.core.data.ModifiableDataObject;
31  import org.opensubsystems.core.error.OSSDataCreateException;
32  import org.opensubsystems.core.error.OSSDataDeleteException;
33  import org.opensubsystems.core.error.OSSDataSaveException;
34  import org.opensubsystems.core.error.OSSException;
35  
36  /**
37   * Base class implementation for database schemas that provide queries or 
38   * operations that allow to modify data in tables managed by this schema. 
39   *  
40   * @version $Id: ModifiableDatabaseSchemaImpl.java,v 1.1 2007/01/10 05:09:38 bastafidli Exp $
41   * @author Miro Halas
42   * @code.reviewer Miro Halas
43   * @code.reviewed Initial revision.
44   */
45  public abstract class ModifiableDatabaseSchemaImpl extends    DatabaseSchemaImpl
46                                                     implements ModifiableDatabaseSchema
47  {
48     // Attributes ///////////////////////////////////////////////////////////////
49  
50     /**
51      * Map of all tables belonging to this schema that can be modified by the
52      * operations provided by the schema (e.g. schema allows insert, update or 
53      * delete on this table). Key is the data type, value is the string with the 
54      * table name.
55      */
56     protected Map   m_mapModifiableTableNames;
57  
58     // Constructors /////////////////////////////////////////////////////////////
59     
60     /**
61      * Constructor allowing to specify attributes for database schema that 
62      * support multiple data object types and therefore have multiple sets of 
63      * tables that can be modified and columns sets. 
64      * 
65      * @param arrDependentSchemas - array of dependent schemas
66      * @param strSchemaName - name of the schema
67      * @param iSchemaVersion - version of the schema
68      * @param bIsInDomain - flag signaling if object is in domain
69      * @param mapModifiableTableNames - map of all tables belonging to this schema
70      *                                 that can be modified by the schema (e.g. 
71      *                                 schema allows insert, update or delete on 
72      *                                 this table)
73      * @throws OSSException - an error has occured
74      */
75     public ModifiableDatabaseSchemaImpl(
76        DatabaseSchema[] arrDependentSchemas,
77        String             strSchemaName,
78        int              iSchemaVersion,
79        boolean          bIsInDomain,
80        Map                mapModifiableTableNames
81     ) throws OSSException
82     {
83        super(arrDependentSchemas, strSchemaName, iSchemaVersion, bIsInDomain);
84        
85        m_mapModifiableTableNames = mapModifiableTableNames;
86     }
87  
88     /**
89      * Constructor allowing to specify attributes for database schema that 
90      * support only single data object type and therefore have most likely only 
91      * one table name that can be modified and single columns sets. 
92      * 
93      * @param arrDependentSchemas - array of dependent schemas
94      * @param strSchemaName - name of the schema
95      * @param iSchemaVersion - version of the schema
96      * @param iModifiableDataType - data type that can be modified using 
97      *                              operations in this schema
98      * @param strModifiableTableName - table belonging to this schema that can be 
99      *                                 modified by the schema (e.g. schema allows
100     *                                 insert, update or delete on this table)
101     * @param bIsInDomain - flag signaling if object is in domain
102     * @throws OSSException - an error has occured
103     */
104    public ModifiableDatabaseSchemaImpl(
105       DatabaseSchema[] arrDependentSchemas,
106       String             strSchemaName,
107       int              iSchemaVersion,
108       boolean          bIsInDomain,
109       Integer            iModifiableDataType,
110       String             strModifiableTableName
111    ) throws OSSException
112    {
113       super(arrDependentSchemas, strSchemaName, iSchemaVersion, bIsInDomain);
114       
115       if ((strModifiableTableName != null) && (strModifiableTableName.length() > 0))
116       {
117          m_mapModifiableTableNames = new HashMap  (1);
118          m_mapModifiableTableNames.put(iModifiableDataType, strModifiableTableName);
119       }
120    }
121 
122    // Logic ////////////////////////////////////////////////////////////////////
123 
124    /**
125     * Method deletes related child data when main data object is being deleted. 
126     * This method has to be overriden for databases that don't support cascade 
127     * delete (eg. Sybase ASE). 
128     * 
129     * @param cntDBConnection - valid connection to database
130     * @param iDataType - data type identifying what to delete
131     * @param iId - ID of the record that has to be deleted
132     * @throws OSSException - problem deleting related data
133     * @throws SQLException - problem deleting related data
134     * @return int - number of deleted records
135     */
136    public int deleteRelatedData(
137       Connection   cntDBConnection,
138       int        iDataType,
139       int        iId
140    ) throws OSSException, 
141             SQLException  
142    {
143       // Default implementation does nothing
144       return 0;
145    }
146 
147    // Helper methods ///////////////////////////////////////////////////////////
148    
149    /**
150     * {@inheritDoc}
151     */
152    public Map   getModifiableTableNames(
153    )
154    {
155       return m_mapModifiableTableNames;
156    }
157 
158    /**
159     * {@inheritDoc}
160     */
161    public void handleSQLException(
162       SQLException   exc,
163       Connection     dbConnection,
164       int          iOperationType, 
165       int          iDataType,
166       Object         data
167    ) throws OSSException
168    {
169       switch (iOperationType)
170       {
171          case (DBOP_INSERT) :
172          {
173             throw new OSSDataCreateException(
174                           "Failed to create data in the database.", exc);
175          }
176          case (DBOP_UPDATE) :
177          {
178             // This will detects conflict when two users tries to modify the 
179             // same data and one of them saves the changes and then other tries 
180             // to overwrite them without knowing that the data were modified
181             if ((exc.getMessage().indexOf("[100]") > -1)
182                && (data instanceof ModifiableDataObject))
183             {
184                Integer   iDataTypeCode = new Integer  (iDataType);
185                
186                DatabaseDataUtils.checkUpdateError(
187                   dbConnection, 
188                   DataConstant.getDataTypeName(iDataTypeCode), 
189                   (String  )getModifiableTableNames().get(iDataTypeCode),
190                   ((ModifiableDataObject)data).getId(), 
191                   ((ModifiableDataObject)data).getModificationTimestamp());
192             }
193             // If this wasn't concurrent modification, throw the generic error
194             throw new OSSDataSaveException(
195                          "Failed to update data in the database.", exc);
196          }
197          case (DBOP_DELETE) :
198          {
199             throw new OSSDataDeleteException(
200                          "Failed to delete data from the database.", exc);
201          }
202          default:
203          {
204             super.handleSQLException(exc, dbConnection, iOperationType, 
205                                      iDataType, data);
206          }
207       }
208    }
209 }
210
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