新特性： MySQL Connector/J 5.1.0 includes the following new features:
* JDBC-4.0 ease-of-development features including auto-registration with the DriverManager via the service provider mechanism, standardized Connection validity checks and categorized SQLExceptions based on recoverability/retry-ability and class of the underlying error.
* JDBC-4.0 standardized unwrapping to interfaces that include vendor extensions
* Support for JDBC-4.0 XML processing via JAXP interfaces to DOM, SAX and StAX
* JDBC-4.0 support for setting per-connection client information (which can be viewed in the comments section of a query via "SHOW PROCESSLIST" on a MySQL server, or can be extended to support custom persistence of the information via a public interface)
* Support for JDBC-4.0 NCHAR, NVARCHAR and NCLOB types
* The driver will automatically adjust the server session variable "net_write_timeout" when it determines its been asked for a "streaming"
result, and resets it to the previous value when the result set has been consumed. (The configuration property is named "netTimeoutForStreamingResults", with a unit of seconds, the value '0' means the driver will not try and adjust this value).