View Javadoc

1   package org.apache.ojb.broker.platforms;
2   
3   /* Copyright 2002-2005 The Apache Software Foundation
4    *
5    * Licensed under the Apache License, Version 2.0 (the "License");
6    * you may not use this file except in compliance with the License.
7    * You may obtain a copy of the License at
8    *
9    *     http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  import java.sql.PreparedStatement;
19  import java.sql.SQLException;
20  import java.sql.Types;
21  
22  /**
23   * This class defines specific behavior for the Derby platform.
24   */
25  public class PlatformDerbyImpl extends PlatformDefaultImpl
26  {
27      /**
28       * {@inheritDoc}
29       */
30      public byte getJoinSyntaxType()
31      {
32          return SQL92_NOPAREN_JOIN_SYNTAX;
33      }
34  
35      /**
36       * {@inheritDoc}
37       */
38      public boolean supportsMultiColumnCountDistinct()
39      {
40          // Currently Derby supports COUNT DISTINCT only for one column
41          return false;
42      }
43  
44      /**
45       * {@inheritDoc}
46       */
47      public void setObjectForStatement(PreparedStatement ps, int index, Object value, int jdbcType) throws SQLException
48      {
49          if (((jdbcType == Types.CHAR) || (jdbcType == Types.VARCHAR)) &&
50              (value instanceof Character))
51          {
52              // [tomdz]
53              // Currently, Derby doesn't like Character objects in the PreparedStatement
54              // when using PreparedStatement#setObject(index, value, jdbcType) method
55              // (see issue DERBY-773)
56              // So we make a String object out of the Character object and use that instead
57              super.setObjectForStatement(ps, index, value.toString(), jdbcType);
58          }
59          else
60          {
61              super.setObjectForStatement(ps, index, value, jdbcType);
62          }
63      }
64  
65      /**
66       * {@inheritDoc}
67       */
68      public String getLastInsertIdentityQuery(String tableName)
69      {
70          // matthias.roth@impart.ch
71          // the function is used by the org.apache.ojb.broker.util.sequence.SequenceManagerNativeImpl
72  		// this call must be made before commit the insert command, so you
73          // must turn off autocommit by seting the useAutoCommit="2"
74          // or use useAutoCommit="1" or use a connection with autoCommit set false
75          // by default (e.g. in managed environments)
76          // transaction demarcation is mandatory
77          return "values IDENTITY_VAL_LOCAL()";
78      }
79  }