MySQL Connector/J 5.1.23 has been released

[Hery Ramilison]

Hello all,

MySQL Connector/J 5.1.23, a maintenance release of the production 5.1
branch has been released. Connector/J is the Type-IV pure-Java JDBC
driver for MySQL.

Version 5.1.23 is suitable for use with many MySQL server versions,
including 4.1, 5.0, 5.1, 5.4, 5.5 and 5.6.

It is now available in source and binary form from the Connector/J
download pages at http://dev.mysql.com/downloads/connector/j/5.1.html
and mirror sites as well as Maven-2 repositories.

As always, we recommend that you check the "CHANGES" file in the
download archive to be aware of changes in behavior that might affect
your application.

* The driver now allows the mechanism for caching MySQL server
configuration values replaceable at runtime, via the
serverConfigCacheFactory property. The default is an
implementation that is a per-VM concurrent map, keyed by URL.
The driver will invalidate cache entries when SQLException
exceptions that indicate communications errors are thrown (on
the assumption that the server has been or is restarting). The
driver also invalidates cache entries if the server version
that is being connected to differs from the one that was
present when the cached values were populated.
To replace the default implementation, implement
CacheAdapterFactory<String, Map<String, String>>, and specify
the fully-qualified class name of this implementation for the
serverConfigCacheFactory connection option.

* Connection.setReadOnly() will take advantage of server-side
support for read-only transactions present in MySQL 5.6 and
newer. Calling .isReadOnly() will incur a round-trip if
useLocalSessionState is not enabled.

* Static charset/collation maps were updated, particularly for
the ucs2_unicode_ci and utf8_unicode_ci collations.

* Added support of password expiration protocol. This introduces
a new Boolean connection property
disconnectOnExpiredPasswords. If
disconnectOnExpiredPasswords=true and the password has
expired, the connection will be rejected by server with
ErrorCode == 1820 (ER_MUST_CHANGE_PASSWORD). If
disconnectOnExpiredPasswords=false, the connection enters
"sandbox" mode, where all commands except SET PASSWORD = ...
and SET PASSWORD FOR CURRENT_USER() = ... cause an error to be
thrown.

* New test cases cover new features from MySQL Server 5.6:

+ Explicit partition selection syntax.

+ EXCHANGE PARTITION syntax.

+ Transportable tablespaces syntax: LOCK TABLES ... FOR
EXPORT.

+ CREATE TABLE ... DATA DIRECTORY =
'/absolute/path/to/directory/' syntax for InnoDB tables.

+ New ALTER TABLE syntax: ALGORITHM and LOCK keywords.

Bugs Fixed

* Stack trace used for point-of-origin in log and exception
messages caused a Permgen leak when an application was
redeployed, because the WebappClassloader could not be garbage
collected. We no longer store the entire stack trace, only the
calling class and method, and only when using the usage
advisor or when profiling. (Bug #16097851, Bug #67954)

* With the connection setting useCompression=true, the SQL
statement LOAD DATA LOCAL INFILE could cause a
java.net.SocketException error due to a broken pipe. (Bug
#15895369, Bug #11237)

* The nativeSQL() method would always truncate fractional
seconds rather than preserving the fractional part in the
output string. Now Connector/J checks the server version: it
preserves the fractional part for MySQL 5.6.4 and greater, and
truncates the fractional part for older versions. (Bug
#14748459, Bug #60598)

* With the new MySQL server password hashing feature enabled,
different results could be returned from ResultSet and
CachedRowSet. The test suite was modified to not perform
comparison of PASSWORD() results when the setting
old_passwords=2, because with SHA-256 password hashing
enabled, the function return results are nondeterministic.
(Bug #14665141)

* The cleanup thread for abandoned connections in the
NonRegisteringDriver class was refactored to have a static
shutdown method. Memory was allocated but never released. If
you encountered this leak problem, implement the context
listener in your application with the
AbandonedConnectionCleanupThread.shutdown() call in the
contextDestroyed method. This issue was found in applications
running under the Tomcat application server; it might have
also applied to other application servers.
For example:
@WebListener
public class YourThreadsListener implements ServletContextListener {
public void contextDestroyed(ServletContextEvent arg0) {
try {
AbandonedConnectionCleanupThread.shutdown();
} catch (InterruptedException e) {
}
}
...
}
Note that if container does not support annotations, you add
the description to web.xml:
<listener>
<listener-class>user.package.YourThreadsListener</listener-class>
</listener>

(Bug #14570236, Bug #65909)

* With the connection parameter rewriteBatchedStatements=true,
ResultSetRow.getTimeFast could give an incorrect value for
TIME columns containing a fractional part. (Bug #14260352)

* executeQuery() in Statement.java let TRUNCATE queries be
executed, although that method is supposed to block any
request that modifies the database. TRUNCATE and RENAME are
now filtered for executeQuery(). (Bug #11748257, Bug #35653)

* If a timestamp value was passed through prepared statement
parameters, fractional-second precision was stripped off, even
if the underlying field (such as VARCHAR(255)) could store the
full value. A workaround was to convert the timestamp value to
a string when specifying the prepared statement argument, for
example prepped_stmt.setString(1,time_stamp.toString(). This
was partly fixed in 5.1.19, but that fix did not cover the
case with the setting useLegacyDatetimeCode=true. (Bug
#11750017, Bug #40279, Bug #60584)

Thanks,
On behalf of the MySQL/ORACLE Build Team

Hery Ramilison