Re: Patch to Village (Oracle Clobs)

FYI, John McNally committed some related code:

From: [email protected]
Subject: cvs commit: village/com/workingdogs/village Value.java
To: [email protected]
Cc: 
Date: Wed, 25 Jun 2003 08:28:06 -0700 (PDT)

jmcnally    03/06/25 08:28:06

  Modified:    com/workingdogs/village Value.java
  Log:
  Patch to Value.java handling of Blobs.  Submitted by Jetspeed developers.
  
  Revision  Changes    Path
  1.19      +12 -3     village/com/workingdogs/village/Value.java
  
  Index: Value.java
  ===================================================================
  RCS file: /home/cvs/village/com/workingdogs/village/Value.java,v
  retrieving revision 1.18
  retrieving revision 1.19
  diff -u -r1.18 -r1.19
  --- Value.java	30 Jul 2002 23:20:51 -0000	1.18
  +++ Value.java	25 Jun 2003 15:28:05 -0000	1.19
  @@ -54,6 +54,7 @@
   package com.workingdogs.village;
   
   import java.math.BigDecimal;
  +import java.sql.Blob;
   import java.sql.PreparedStatement;
   import java.sql.ResultSet;
   import java.sql.SQLException;
  @@ -67,7 +68,7 @@
   cross between a row and column and contains the information held there.
   
   @author Jon S. Stevens <A HREF="mailto:[email protected]">[email protected]</A>
  -@version $Revision: 1.18 $
  +@version $Revision: 1.19 $
   */
   public class Value
   {
  @@ -149,10 +150,14 @@
               case Types.LONGVARBINARY:
               case Types.VARBINARY:
               case Types.BINARY:
  -            case Types.BLOB:
                   valueObject = rs.getBytes (columnNumber);
                   break;
   
  +            case Types.BLOB:
  +                Blob blob = rs.getBlob(columnNumber);
  +                valueObject = blob.getBytes(1, (int) blob.length());
  +                break;
  +
               case Types.LONGVARCHAR:
               case Types.CHAR:
               case Types.VARCHAR:
  @@ -264,7 +269,11 @@
               case Types.VARBINARY:
               case Types.BINARY:
               case Types.BLOB:
  -                stmt.setBytes (stmtNumber, this.asBytes());
  +                // The following form is reported to work and be necessary for
  +                // Oracle when the blob exceeds 4k.
  +                byte[] value = this.asBytes();
  +                stmt.setBinaryStream(stmtNumber, 
  +                        new java.io.ByteArrayInputStream(value), value.length);
                   break;
   
               case Types.LONGVARCHAR:
  


Scott Miller <[email protected]> writes:

> Hi,
> 
> I have been trying to use Torque as a database abstraction layer for an Oracle 
> database containing CLOBs.  However, Village does not properly retrieve or set 
> CLOB values with Oracle.  This is because Village uses the ResultSet.getString 
> method to read the CLOB value from the database and the 
> PreparedStatement.setString method to set the CLOB value.  This approach will 
> work for many JDBC drivers because they support the handling of CLOBs as 
> Strings.  However, the Oracle JDBC driver does not support this conversition.  
> I have modified Value.java to properly handle Oracle clobs.  This file is 
> attached to this email.  I am not sure of the proper avenue to submit a patch 
> for Village, so I am hoping that someone can advise me on the best course of 
> action.  The rest of this email is devoted to a brief explanation of the code 
> change.
> 
> Because Oracle's JDBC driver does not support the CLOB to String conversion, 
> you need to actually use the java.sql.Clob interface, which is implemented by 
> oracle.sql.CLOB.  You can refer to the Clob object by the java.sql.Clob 
> interface during data retrieval, because there is no need to instantiate an 
> instance of the Class.  The constructor of the Value class was modified to 
> handle retrieval by simply adding a Types.CLOB case to the switch statement.  
> 
> Unfortunately, you need to create an instance of the clob object when you want 
> to set the CLOB data, so you must refer to the oracle.sql.CLOB class.  
> However, in order to not rely on the Oracle JDBC driver at compile time, I 
> have writted the code to use reflection to create an instance of 
> oracle.sql.CLOB and set the value.  This code is located in the 
> setPreparedStatementValue method of the Value class.
> 
> Any advice on how to submit this update would be appreciated.
> 
> Thanks,
> 
> Scott
> 
> 
> 
> 
> _______________________________________________
> Village-dev mailing list
> [email protected]
> http://share.whichever.com/mailman/listinfo/village-dev

-- 

Daniel Rall