The interface that every driver class must implement.
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")
See Also
Public Method Summary
abstract boolean |
acceptsURL(String url)
Retrieves whether the driver thinks that it can open a connection
to the given URL.
|
abstract Connection | |
abstract int |
getMajorVersion()
Retrieves the driver's major version number.
|
abstract int |
getMinorVersion()
Gets the driver's minor version number.
|
abstract DriverPropertyInfo[] |
getPropertyInfo(String url, Properties info)
Gets information about the possible properties for this driver.
|
abstract boolean |
jdbcCompliant()
Reports whether this driver is a genuine JDBC
CompliantTM driver.
|
Public Methods
public abstract boolean acceptsURL (String url)
Retrieves whether the driver thinks that it can open a connection
to the given URL. Typically drivers will return true
if they
understand the subprotocol specified in the URL and false
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 |
---|
public abstract Connection connect (String url, Properties info)
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 java.util.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 the Properties
object.
Parameters
url | the URL of the database to which to connect |
---|---|
info | 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 |
---|
public abstract int getMajorVersion ()
Retrieves the driver's major version number. Initially this should be 1.
Returns
- this driver's major version number
public abstract int getMinorVersion ()
Gets the driver's minor version number. Initially this should be 0.
Returns
- this driver's minor version number
public abstract DriverPropertyInfo[] getPropertyInfo (String url, Properties info)
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 the getPropertyInfo
method.
Parameters
url | the URL of the database to which to connect |
---|---|
info | 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 |
---|
public abstract boolean jdbcCompliant ()
Reports whether this driver is a genuine JDBC
CompliantTM driver.
A driver may only report true
here if it passes the JDBC
compliance tests; otherwise it is required to return false
.
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