patch for jdbc BigDecimal bug

Patch applied. Thanks.

Attached is a simple one line patch for the problem reported in the
following email.

thanks,
--Barry

-----Original Message-----
From: Barry Lind [mailto:barry@xythos.com]
Sent: Tuesday, August 21, 2001 11:45 AM
To: Jason Orendorff
Cc: pgsql-interfaces@postgresql.org; pgsql-jdbc@postgresql.org
Subject: Re: [INTERFACES] Bad BigDecimal

Yes this does appear to be a bug. Can you submit a patch to
pgsql-patches@postgresql.org with the fix. If you don't have time, let
me know and I will submit the patch.

thanks,
--Barry

Jason Orendorff wrote:

Reply-To: sender

Hi. I'm having a problem with the JDBC driver. It's excellent for
the most part - kudos to Mr. Mount - and this is the first problem
I've run into. I think there's a bug; read below for my explanation
and (I think) the fix.

The problem: When I call getBigDecimal() on a ResultSet, it
sometimes throws an exception:

Bad BigDecimal 174.50
at org.postgresql.jdbc2.ResultSet.getBigDecimal(ResultSet.java:373)
at org.postgresql.jdbc2.ResultSet.getBigDecimal(ResultSet.java:984)
...blah blah blah...
org.postgresql.util.PSQLException: Bad BigDecimal 174.50

I think the problem is on line 984 of
org/postgresql/jdbc2/ResultSet.java. Here's the method I'm looking at
(slightly reformatted to fit in this e-mail message):

public java.math.BigDecimal getBigDecimal(int columnIndex)
throws SQLException
{
// Now must call BigDecimal with a scale otherwise JBuilder
// barfs
return getBigDecimal(columnIndex,0);
}

Notice that it's calling getBigDecimal(int, int) with a 0 for the
second argument. Here's the source of that method (again, slightly
reformatted):

public BigDecimal getBigDecimal(int columnIndex, int scale)
throws SQLException
{
String s = getFixedString(columnIndex);
BigDecimal val;

if (s != null)
{

try
{
val = new BigDecimal(s);
} catch (NumberFormatException e) {
throw new PSQLException("postgresql.res.badbigdec",s);
}
if (scale==-1) return val;
try
{
return val.setScale(scale);
} catch (ArithmeticException e) {
throw new PSQLException("postgresql.res.badbigdec",s);
}
}
return null; // SQL NULL
}

Okay. The fact that the default scale is 0 causes essentially
the following to happen:
BigDecimal val;
val = new BigDecimal("174.50");
return val.setScale(0);

This causes an exception because 174.50 can't be exactly represented
by a BigDecimal that has scale 0.

The fix: change the appropriate line to read:
return getBigDecimal(columnIndex, -1);

I'm sure I'm probably overlooking something; please let me know...
Also, please copy me on replies! Thanks!

*** ./src/interfaces/jdbc/org/postgresql/jdbc2/ResultSet.java.orig	Wed Aug 22 02:56:25 2001
--- ./src/interfaces/jdbc/org/postgresql/jdbc2/ResultSet.java	Wed Aug 22 03:57:18 2001
***************
*** 798,805 ****

public java.math.BigDecimal getBigDecimal(int columnIndex) throws SQLException
{
! // Now must call BigDecimal with a scale otherwise JBuilder barfs
! return getBigDecimal(columnIndex,0);
}

public java.math.BigDecimal getBigDecimal(String columnName) throws SQLException
--- 798,804 ----

public java.math.BigDecimal getBigDecimal(int columnIndex) throws SQLException
{
! return getBigDecimal(columnIndex,-1);
}

public java.math.BigDecimal getBigDecimal(String columnName) throws SQLException

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