DerbyCaseFragment


1   //$Id: DerbyCaseFragment.java,v 1.2 2004/09/29 12:29:05 pgmjsd Exp $
2   package org.hibernate.sql;
3   
4   import java.util.Iterator  ;
5   import java.util.Map  ;
6   
7   /**
8    * @author Simon Johnston
9    * @see org.hibernate.dialect.DerbyDialect
10   */
11  public class DerbyCaseFragment extends CaseFragment {
12  
13      /**
14       * From http://www.jroller.com/comments/kenlars99/Weblog/cloudscape_soon_to_be_derby
15       * <p/>
16       * The problem we had, was when Hibernate does a select with a case statement, for joined subclasses.
17       * This seems to be because there was no else at the end of the case statement (other dbs seem to not mind).
18       */
19      public String   toFragmentString() {
20          StringBuffer   buf = new StringBuffer  ( cases.size() * 15 + 10 );
21          buf.append( "case" );                               //$NON-NLS-1
22          Iterator   iter = cases.entrySet().iterator();
23          while ( iter.hasNext() ) {
24              Map.Entry   me = ( Map.Entry   ) iter.next();
25              buf.append( " when " )//$NON-NLS-1
26                      .append( me.getKey() )
27                      .append( " is not null then " )//$NON-NLS-1
28                      .append( me.getValue() );
29          }
30          // null is not considered the same type as Integer.
31          buf.append( " else -1" );                               //$NON-NLS-1
32          buf.append( " end" );                                   //$NON-NLS-1
33          if ( returnColumnName != null ) {
34              buf.append( " as " )//$NON-NLS-1
35                      .append( returnColumnName );
36          }
37          return buf.toString();
38      }
39  }
40
A to Z: JavaDoc & Examples Daily Java News & Articles Open Source Projects Open Source Codes Free Computer Books Remove Frame
Popular Tags