The Java SQL framework allows for multiple database drivers.
Each driver should supply a class that implements the Driver interface.
The DriverManager will try to load as many drivers as it can find and then for any given connection request, it will ask each driver in turn to try to connect to the target URL.
It is strongly recommended that each Driver class should be small and standalone so that the Driver class can be loaded and queried without bringing in vast quantities of supporting code.
When a Driver class is loaded, it should create an instance of itself and register it with the DriverManager. This means that a user can load and register a driver by calling:
Class.forName("foo.bah.Driver")
A JDBC driver may create a DriverAction implementation in order to receive notifications when DriverManager.deregisterDriver(java.sql.Driver) has been called.
- Since:
- 1.1
- See Also:
DriverManager
,Connection
,DriverAction
-
Method Summary
Modifier and TypeMethodDescriptionboolean
acceptsURL(String url)
Retrieves whether the driver thinks that it can open a connection to the given URL.connect(String url, Properties info)
Attempts to make a database connection to the given URL.int
Retrieves the driver's major version number.int
Gets the driver's minor version number.Return the parent Logger of all the Loggers used by this driver.getPropertyInfo(String url, Properties info)
Gets information about the possible properties for this driver.boolean
Reports whether this driver is a genuine JDBC Compliant driver.
-
Method Details
-
connect
Attempts to make a database connection to the given URL. The driver should return "null" if it realizes it is the wrong kind of driver to connect to the given URL. This will be common, as when the JDBC driver manager is asked to connect to a given URL it passes the URL to each loaded driver in turn.The driver should throw an
SQLException
if it is the right driver to connect to the given URL but has trouble connecting to the database.The
Properties
argument can be used to pass arbitrary string tag/value pairs as connection arguments. Normally at least "user" and "password" properties should be included in theProperties
object.Note: If a property is specified as part of the
url
and is also specified in theProperties
object, it is implementation-defined as to which value will take precedence. For maximum portability, an application should only specify a property once.- Parameters:
url
- the URL of the database to which to connectinfo
- a list of arbitrary string tag/value pairs as connection arguments. Normally at least a "user" and "password" property should be included.- Returns:
- a
Connection
object that represents a connection to the URL - Throws:
SQLException
- if a database access error occurs or the url isnull
-
acceptsURL
Retrieves whether the driver thinks that it can open a connection to the given URL. Typically drivers will returntrue
if they understand the sub-protocol specified in the URL andfalse
if they do not.- Parameters:
url
- the URL of the database- Returns:
true
if this driver understands the given URL;false
otherwise- Throws:
SQLException
- if a database access error occurs or the url isnull
-
getPropertyInfo
Gets information about the possible properties for this driver.The
getPropertyInfo
method is intended to allow a generic GUI tool to discover what properties it should prompt a human for in order to get enough information to connect to a database. Note that depending on the values the human has supplied so far, additional values may become necessary, so it may be necessary to iterate though several calls to thegetPropertyInfo
method.- Parameters:
url
- the URL of the database to which to connectinfo
- a proposed list of tag/value pairs that will be sent on connect open- Returns:
- an array of
DriverPropertyInfo
objects describing possible properties. This array may be an empty array if no properties are required. - Throws:
SQLException
- if a database access error occurs
-
getMajorVersion
int getMajorVersion()Retrieves the driver's major version number. Initially this should be 1.- Returns:
- this driver's major version number
-
getMinorVersion
int getMinorVersion()Gets the driver's minor version number. Initially this should be 0.- Returns:
- this driver's minor version number
-
jdbcCompliant
boolean jdbcCompliant()Reports whether this driver is a genuine JDBC Compliant driver. A driver may only reporttrue
here if it passes the JDBC compliance tests; otherwise it is required to returnfalse
.JDBC compliance requires full support for the JDBC API and full support for SQL 92 Entry Level. It is expected that JDBC compliant drivers will be available for all the major commercial databases.
This method is not intended to encourage the development of non-JDBC compliant drivers, but is a recognition of the fact that some vendors are interested in using the JDBC API and framework for lightweight databases that do not support full database functionality, or for special databases such as document information retrieval where a SQL implementation may not be feasible.
- Returns:
true
if this driver is JDBC Compliant;false
otherwise
-
getParentLogger
Return the parent Logger of all the Loggers used by this driver. This should be the Logger farthest from the root Logger that is still an ancestor of all of the Loggers used by this driver. Configuring this Logger will affect all of the log messages generated by the driver. In the worst case, this may be the root Logger.- Returns:
- the parent Logger for this driver
- Throws:
SQLFeatureNotSupportedException
- if the driver does not usejava.util.logging
.- Since:
- 1.7
-