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1   package org.apache.torque.adapter;
2   
3   /*
4    * Licensed to the Apache Software Foundation (ASF) under one
5    * or more contributor license agreements.  See the NOTICE file
6    * distributed with this work for additional information
7    * regarding copyright ownership.  The ASF licenses this file
8    * to you under the Apache License, Version 2.0 (the
9    * "License"); you may not use this file except in compliance
10   * with the License.  You may obtain a copy of the License at
11   *
12   *   http://www.apache.org/licenses/LICENSE-2.0
13   *
14   * Unless required by applicable law or agreed to in writing,
15   * software distributed under the License is distributed on an
16   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17   * KIND, either express or implied.  See the License for the
18   * specific language governing permissions and limitations
19   * under the License.
20   */
21  
22  import java.sql.Connection;
23  import java.sql.SQLException;
24  import java.sql.Statement;
25  
26  /***
27   * This is used to connect to SapDB databases.
28   *
29   * <a href="http://www.sapdb.org">http://www.sapdb.org</a>
30   *
31   * @author <a href="mailto:dave.polito@planetcad.com">Dave Polito</a>
32   * @version $Id: DBSapDB.java 473821 2006-11-11 22:37:25Z tv $
33   */
34  public class DBSapDB extends AbstractDBAdapter
35  {
36      /***
37       * Serial version
38       */
39      private static final long serialVersionUID = 8277068258155186370L;
40  
41      /***
42       * Empty constructor.
43       */
44      protected DBSapDB()
45      {
46      }
47  
48      /***
49       * This method is used to ignore case.
50       *
51       * @param in The string to transform to upper case.
52       * @return The upper case string.
53       */
54      public String toUpperCase(String in)
55      {
56          return new StringBuffer("UPPER(").append(in).append(")").toString();
57      }
58  
59      /***
60       * This method is used to ignore case.
61       *
62       * @param in The string whose case to ignore.
63       * @return The string in a case that can be ignored.
64       */
65      public String ignoreCase(String in)
66      {
67          return new StringBuffer("UPPER(").append(in).append(")").toString();
68      }
69  
70      /***
71       * @see org.apache.torque.adapter.DB#getIDMethodType()
72       */
73      public String getIDMethodType()
74      {
75          return SEQUENCE;
76      }
77  
78      /***
79       * Returns the next key from a sequence.  Uses the following
80       * implementation:
81       *
82       * <blockquote><code><pre>
83       * select sequenceName.nextval from dual
84       * </pre></code></blockquote>
85       *
86       * @param sequenceName The name of the sequence (should be of type
87       * <code>String</code>).
88       * @return SQL to retreive the next database key.
89       * @see org.apache.torque.adapter.DB#getIDMethodSQL(Object)
90       */
91      public String getIDMethodSQL(Object sequenceName)
92      {
93          return ("select " + sequenceName + ".nextval from dual");
94      }
95  
96      /***
97       * Locks the specified table.
98       *
99       * @param con The JDBC connection to use.
100      * @param table The name of the table to lock.
101      * @exception SQLException No Statement could be created or executed.
102      */
103     public void lockTable(Connection con, String table) throws SQLException
104     {
105         Statement statement = con.createStatement();
106 
107         StringBuffer stmt = new StringBuffer();
108         stmt.append("SELECT next_id FROM ")
109         .append(table)
110         .append(" FOR UPDATE");
111 
112         statement.executeQuery(stmt.toString());
113     }
114 
115    /***
116     * This method is for the SqlExpression.quoteAndEscape rules.  The rule is,
117     * any string in a SqlExpression with a BACKSLASH will either be changed to
118     * "//" or left as "\".  SapDB does not need the escape character.
119     *
120     * @return false.
121     */
122 
123     public boolean escapeText()
124     {
125         return false;
126     }
127 
128     /***
129      * Unlocks the specified table.
130      *
131      * @param con The JDBC connection to use.
132      * @param table The name of the table to unlock.
133      * @exception SQLException No Statement could be created or
134      * executed.
135      */
136     public void unlockTable(Connection con, String table) throws SQLException
137     {
138         // Tables in SapDB are unlocked when a commit is issued.  The
139         // user may have issued a commit but do it here to be sure.
140         con.commit();
141     }
142 }