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Attached is a patch to add bytea support to JDBC.

This patch does the following:

- Adds binary datatype support (bytea)
- Changes getXXXStream()/setXXXStream() methods to be spec compliant
- Adds ability to revert to old behavior

Details:

Adds support for the binary type bytea.  The ResultSet.getBytes() and
PreparedStatement.setBytes() methods now work against columns of bytea
type.  This is a change in behavior from the previous code which assumed
the column type was OID and thus a LargeObject.  The new behavior is
more complient with the JDBC spec as BLOB/CLOB are to be used for
LargeObjects and the getBytes()/setBytes() methods are for the databases
binary datatype (which is bytea in postgres).

Changes the behavior of the getBinaryStream(), getAsciiStream(),
getCharacterStream(), getUnicodeStream() and their setXXXStream()
counterparts.  These methos now work against either the bytea type
(BinaryStream) or the text types (AsciiStream, CharacterStream,
UnicodeStream).  The previous behavior was that these all assumed the
underlying column was of type OID and thus a LargeObject.  The
spec/javadoc for these methods indicate that they are for LONGVARCHAR
and LONGVARBINARY datatypes, which are distinct from the BLOB/CLOB
datatypes.  Given that the bytea and text types support upto 1G, they
are the LONGVARBINARY and LONGVARCHAR datatypes in postgres.

Added support for turning off the above new functionality.  Given that
the changes above are not backwardly compatible (however they are more
spec complient), I added the ability to revert back to the old behavior.
  The Connection now takes an optional parameter named 'compatible'.  If
the value of '7.1' is passed, the driver reverts to the 7.1 behavior.
If the parameter is not passed or the value '7.2' is passed the behavior
is the new behavior.  The mechanism put in place can be used in the
future when/if similar needs arise to change behavior.  This is
patterned after how Oracle does this (i.e. Oracle has a 'compatible'
parameter that behaves in a similar manner).

Misc fixes.  Cleaned up a few things I encountered along the way.


Note that in testing the patch I needed to ignore whitespace differences
in order to get it to apply cleanly (i.e. patch -l -i byteapatch.diff).
Also this patch introduces a new file
(src/interfaces/jdbc/org/postgresql/util/PGbytea.java).

Barry Lind
This commit is contained in:
Bruce Momjian
2001-09-10 15:07:05 +00:00
parent 6b50f9af33
commit ec0ad67403
10 changed files with 557 additions and 49 deletions

View File

@ -85,12 +85,26 @@ public class Driver implements java.sql.Driver
* database.
*
* <p>The java.util.Properties argument can be used to pass arbitrary
* string tag/value pairs as connection arguments. Normally, at least
* string tag/value pairs as connection arguments.
*
* user - (optional) The user to connect as
* password - (optional) The password for the user
* charSet - (optional) The character set to be used for converting
* to/from the database to unicode. If multibyte is enabled on the
* server then the character set of the database is used as the default,
* otherwise the jvm character encoding is used as the default.
* compatible - This is used to toggle
* between different functionality as it changes across different releases
* of the jdbc driver code. The values here are versions of the jdbc
* client and not server versions. For example in 7.1 get/setBytes
* worked on LargeObject values, in 7.2 these methods were changed
* to work on bytea values. This change in functionality could
* be disabled by setting the compatible level to be "7.1", in
* which case the driver will revert to the 7.1 functionality.
*
* <p>Normally, at least
* "user" and "password" properties should be included in the
* properties. In addition, the "charSet" property can be used to
* set a character set encoding (e.g. "utf-8") other than the platform
* default (typically Latin1). This is necessary in particular if storing
* multibyte characters in the database. For a list of supported
* properties. For a list of supported
* character encoding , see
* http://java.sun.com/products/jdk/1.2/docs/guide/internat/encoding.doc.html
* Note that you will probably want to have set up the Postgres database