Class DriverManager
NOTE: The DataSource
interface, provides
another way to connect to a data source.
The use of a DataSource
object is the preferred means of
connecting to a data source.
As part of its initialization, the DriverManager
class will
attempt to load available JDBC drivers by using:
- The
jdbc.drivers
system property which contains a colon separated list of fully qualified class names of JDBC drivers. Each driver is loaded using the system class loader:jdbc.drivers=foo.bah.Driver:wombat.sql.Driver:bad.taste.ourDriver
- Service providers of the
java.sql.Driver
class, that are loaded via the service-provider loading mechanism.
- Implementation Note:
DriverManager
initialization is done lazily and looks up service providers using the thread context class loader. The drivers loaded and available to an application will depend on the thread context class loader of the thread that triggers driver initialization byDriverManager
.When the method
getConnection
is called, theDriverManager
will attempt to locate a suitable driver from amongst those loaded at initialization and those loaded explicitly using the same class loader as the current application.- Since:
- 1.1
- See Also:
-
Method Summary
Modifier and TypeMethodDescriptionstatic void
deregisterDriver
(Driver driver) Removes the specified driver from theDriverManager
's list of registered drivers.drivers()
Retrieves a Stream with all of the currently loaded JDBC drivers to which the current caller has access.static Connection
getConnection
(String url) Attempts to establish a connection to the given database URL.static Connection
getConnection
(String url, String user, String password) Attempts to establish a connection to the given database URL.static Connection
getConnection
(String url, Properties info) Attempts to establish a connection to the given database URL.static Driver
Attempts to locate a driver that understands the given URL.static Enumeration
<Driver> Retrieves an Enumeration with all of the currently loaded JDBC drivers to which the current caller has access.static int
Gets the maximum time in seconds that a driver can wait when attempting to log in to a database.static PrintStream
Deprecated.static PrintWriter
Retrieves the log writer.static void
Prints a message to the current JDBC log stream.static void
registerDriver
(Driver driver) Registers the given driver with theDriverManager
.static void
registerDriver
(Driver driver, DriverAction da) Registers the given driver with theDriverManager
.static void
setLoginTimeout
(int seconds) Sets the maximum time in seconds that a driver will wait while attempting to connect to a database once the driver has been identified.static void
setLogStream
(PrintStream out) Deprecated.UsesetLogWriter
static void
setLogWriter
(PrintWriter out) Sets the logging/tracingPrintWriter
object that is used by theDriverManager
and all drivers.
-
Method Details
-
getLogWriter
Retrieves the log writer. ThegetLogWriter
andsetLogWriter
methods should be used instead of theget/setlogStream
methods, which are deprecated.- Returns:
- a
java.io.PrintWriter
object - Since:
- 1.2
- See Also:
-
setLogWriter
Sets the logging/tracingPrintWriter
object that is used by theDriverManager
and all drivers.If a security manager exists, its
checkPermission
method is first called with aSQLPermission("setLog")
permission to check that the caller is allowed to callsetLogWriter
.- Parameters:
out
- the new logging/tracingPrintStream
object;null
to disable logging and tracing- Throws:
SecurityException
- if a security manager exists and itscheckPermission
method denies permission to set the log writer.- Since:
- 1.2
- See Also:
-
getConnection
Attempts to establish a connection to the given database URL. TheDriverManager
attempts to select an appropriate driver from the set of registered JDBC drivers.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
- a database url of the formjdbc:subprotocol:subname
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 to the URL
- Throws:
SQLException
- if a database access error occurs or the url isnull
SQLTimeoutException
- when the driver has determined that the timeout value specified by thesetLoginTimeout
method has been exceeded and has at least tried to cancel the current database connection attempt
-
getConnection
public static Connection getConnection(String url, String user, String password) throws SQLException Attempts to establish a connection to the given database URL. TheDriverManager
attempts to select an appropriate driver from the set of registered JDBC drivers.Note: If the
user
orpassword
property are also specified as part of theurl
, it is implementation-defined as to which value will take precedence. For maximum portability, an application should only specify a property once.- Parameters:
url
- a database url of the formjdbc:subprotocol:subname
user
- the database user on whose behalf the connection is being madepassword
- the user's password- Returns:
- a connection to the URL
- Throws:
SQLException
- if a database access error occurs or the url isnull
SQLTimeoutException
- when the driver has determined that the timeout value specified by thesetLoginTimeout
method has been exceeded and has at least tried to cancel the current database connection attempt
-
getConnection
Attempts to establish a connection to the given database URL. TheDriverManager
attempts to select an appropriate driver from the set of registered JDBC drivers.- Parameters:
url
- a database url of the formjdbc:subprotocol:subname
- Returns:
- a connection to the URL
- Throws:
SQLException
- if a database access error occurs or the url isnull
SQLTimeoutException
- when the driver has determined that the timeout value specified by thesetLoginTimeout
method has been exceeded and has at least tried to cancel the current database connection attempt
-
getDriver
Attempts to locate a driver that understands the given URL. TheDriverManager
attempts to select an appropriate driver from the set of registered JDBC drivers.- Parameters:
url
- a database URL of the formjdbc:subprotocol:subname
- Returns:
- a
Driver
object representing a driver that can connect to the given URL - Throws:
SQLException
- if a database access error occurs
-
registerDriver
Registers the given driver with theDriverManager
. A newly-loaded driver class should call the methodregisterDriver
to make itself known to theDriverManager
. If the driver is currently registered, no action is taken.- Parameters:
driver
- the new JDBC Driver that is to be registered with theDriverManager
- Throws:
SQLException
- if a database access error occursNullPointerException
- ifdriver
is null
-
registerDriver
Registers the given driver with theDriverManager
. A newly-loaded driver class should call the methodregisterDriver
to make itself known to theDriverManager
. If the driver is currently registered, no action is taken.- Parameters:
driver
- the new JDBC Driver that is to be registered with theDriverManager
da
- theDriverAction
implementation to be used whenDriverManager#deregisterDriver
is called- Throws:
SQLException
- if a database access error occursNullPointerException
- ifdriver
is null- Since:
- 1.8
-
deregisterDriver
Removes the specified driver from theDriverManager
's list of registered drivers.If a
null
value is specified for the driver to be removed, then no action is taken.If a security manager exists, its
checkPermission
method is first called with aSQLPermission("deregisterDriver")
permission to check that the caller is allowed to deregister a JDBC Driver.If the specified driver is not found in the list of registered drivers, then no action is taken. If the driver was found, it will be removed from the list of registered drivers.
If a
DriverAction
instance was specified when the JDBC driver was registered, its deregister method will be called prior to the driver being removed from the list of registered drivers.- Parameters:
driver
- the JDBC Driver to remove- Throws:
SQLException
- if a database access error occursSecurityException
- if a security manager exists and itscheckPermission
method denies permission to deregister a driver.- See Also:
-
getDrivers
Retrieves an Enumeration with all of the currently loaded JDBC drivers to which the current caller has access.Note: The classname of a driver can be found using
d.getClass().getName()
- Returns:
- the list of JDBC Drivers loaded by the caller's class loader
- See Also:
-
drivers
-
setLoginTimeout
public static void setLoginTimeout(int seconds) Sets the maximum time in seconds that a driver will wait while attempting to connect to a database once the driver has been identified.- Parameters:
seconds
- the login time limit in seconds; zero means there is no limit- See Also:
-
getLoginTimeout
public static int getLoginTimeout()Gets the maximum time in seconds that a driver can wait when attempting to log in to a database.- Returns:
- the driver login time limit in seconds
- See Also:
-
setLogStream
Deprecated.UsesetLogWriter
Sets the logging/tracing PrintStream that is used by theDriverManager
and all drivers.If a security manager exists, its
checkPermission
method is first called with aSQLPermission("setLog")
permission to check that the caller is allowed to callsetLogStream
.- Parameters:
out
- the new logging/tracing PrintStream; to disable, set tonull
- Throws:
SecurityException
- if a security manager exists and itscheckPermission
method denies permission to set the log stream.- See Also:
-
getLogStream
Deprecated.UsegetLogWriter
Retrieves the logging/tracing PrintStream that is used by theDriverManager
and all drivers.- Returns:
- the logging/tracing PrintStream; if disabled, is
null
- See Also:
-
println
Prints a message to the current JDBC log stream.- Parameters:
message
- a log or tracing message
-
getLogWriter