Package org.apache.jena.jdbc

Class JenaDriver

java.lang.Object

org.apache.jena.jdbc.JenaDriver

All Implemented Interfaces:

Driver

Direct Known Subclasses:

MemDriver, RemoteEndpointDriver, TDBDriver

public abstract class JenaDriver
extends Object
implements Driver

Abstract implementation of a Jena JDBC driver

Connection URLs

All Jena JDBC drivers are expected to have connection URLs which start with the following:

 jdbc:jena:foo:
 

The jdbc:jena: portion is the common prefix for all Jena JDBC drivers, the foo: portion is an implementation specific prefix. Each Jena JDBC driver will have a different foo: prefix chosen such that it appropriately identifies at a glance the type of the underlying RDF database.

Connection URL Parameters

After the prefix a Jena JDBC connection URL consists of a sequence of key value pairs, the characters ampersand (&), semicolon (;) and pipe (|) are considered to be separators between pairs, the separators are reserved characters and may not be used in values. The key is separated from the value by a equals sign (=) though unlike the separators this is not a reserved character in values.

There is no notion of character escaping in connection parameters so if you need to use any of the reserved characters in your values then you should pass these to the connect(String, Properties) method directly in the Properties object.

Common Parameters

There are some common parameter understood by all Jena JDBC drivers and which apply regardless of driver implementation.

JDBC Compatibility Level

The first of these is the jdbc-compatibility parameter. To avoid typos when creating URLs programmatically a constant ( PARAM_JDBC_COMPATIBILITY) is provided which contains the parameter name exactly as the code expects it. This parameter provides an integer value in the range 1-9 which denotes how compatible the driver should attempt to be, see JdbcCompatibility for discussion on the meaning of compatibility levels.

When not set the JdbcCompatibility.DEFAULT compatibility level is used, note that JenaConnection objects support changing this after the connection has been established.

Pre-Processors

The second of these is the pre-processor parameter which is used to specify one/more CommandPreProcessor implementations to use. The parameter should be specified once for each pre-processor you wish to you and you should supply a fully qualified class name to ensure the pre-processor can be loaded and registered on your connections. The driver will report an error if you specify a class that cannot be appropriately loaded and registered.

Pre-processors are registered in the order that they are specified so if you use multiple pre-processors and they have ordering dependencies please ensure that you specify them in the desired order. Note that JenaConnection objects support changing registered pre-processors after the connection has been established.

Post-Processors

There is also a post-processor parameter which is used to specify one/more ResultsPostProcessor implementations to use. The parameter should be specified once for each post-processor you wish to use and you should supply a fully qualified class name to ensure the post-processor can be loaded and registered on your connections. The driver will report an error is you specify a class that cannot be appropriately loaded and registered.

Post-processors are registered in the order that they are specified so if you use multiple post-processors and they have ordering dependencies please ensure that you specify them in the desired order. Note that JenaConnection objects support changing registered post-processors after the connection has been established.

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DRIVER_PREFIX	Constant for the primary Jena JDBC Driver prefix, implementations supply an additional prefix which will form the next portion of the JDBC URL
static final String	NO_AUTO_LOGGING_CONFIGURATION	Deprecated.
static final String	PARAM_CONFIG	Constant for the connection URL parameter used to set the path to a Java properties file used to provide additional connection parameters external to the URL.
static final String	PARAM_JDBC_COMPATIBILITY	Constant for the connection URL parameter which sets the desired JDBC compatibility level
static final String	PARAM_LOGGING	Deprecated. No longer supported as of Jena 4.x
static final String	PARAM_PASSWORD	Constant for the standard JDBC connection URL parameter used to set password for drivers that support authentication
static final String	PARAM_POST_PROCESSOR	Constant for the connection URL parameter used to set class names of ResultsPostProcessor implementations to use with returned connections.
static final String	PARAM_PRE_PROCESSOR	Constant for the connection URL parameter used to set class names of CommandPreProcessor implementations to use with returned connections.
static final String	PARAM_USERNAME	Constant for the standard JDBC connection URL parameter used to set user name for drivers that support authentication

Constructor Summary

Constructors

Constructor	Description
JenaDriver(int majorVer, int minorVer, String prefix)	Creates a new driver

Method Summary

Modifier and Type	Method	Description
boolean	acceptsURL(String url)
final Connection	connect(String url, Properties props)
int	getMajorVersion()
int	getMinorVersion()
Logger	getParentLogger()
final DriverPropertyInfo[]	getPropertyInfo(String url, Properties props)
final boolean	jdbcCompliant()	Returns that a Jena JDBC driver is not JDBC compliant since strict JDBC compliance requires support for SQL-92 and since we are using SPARQL we don't meet that criteria

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

DRIVER_PREFIX

public static final String DRIVER_PREFIX

Constant for the primary Jena JDBC Driver prefix, implementations supply an additional prefix which will form the next portion of the JDBC URL

See Also:

• Constant Field Values

PARAM_JDBC_COMPATIBILITY

public static final String PARAM_JDBC_COMPATIBILITY

Constant for the connection URL parameter which sets the desired JDBC compatibility level

See Also:

• Constant Field Values

PARAM_PRE_PROCESSOR

public static final String PARAM_PRE_PROCESSOR

Constant for the connection URL parameter used to set class names of CommandPreProcessor implementations to use with returned connections.

This parameter may be specified multiple times and pre-processors will be registered (and thus applied) in the order specified. If any pre-processors are passed as part of the Properties object rather than in the connection URL then these will be registered (and thus applied) prior to those specified in the connection URL.

See Also:

• Constant Field Values

PARAM_POST_PROCESSOR

public static final String PARAM_POST_PROCESSOR

Constant for the connection URL parameter used to set class names of ResultsPostProcessor implementations to use with returned connections.

This parameter may be specified multiple times and post-processors will be registered (and thus applied) in the order specified. If any post-processors are passed as part of the Properties object rather than in the connection URL then these will be registered (and thus applied) prior to those specified in the connection URL.

See Also:

• Constant Field Values

PARAM_USERNAME

public static final String PARAM_USERNAME

Constant for the standard JDBC connection URL parameter used to set user name for drivers that support authentication

See Also:

• Constant Field Values

PARAM_PASSWORD

public static final String PARAM_PASSWORD

Constant for the standard JDBC connection URL parameter used to set password for drivers that support authentication

See Also:

• Constant Field Values

PARAM_LOGGING

@Deprecated
public static final String PARAM_LOGGING

Deprecated.

No longer supported as of Jena 4.x

Old connection URL property for having the driver configure logging, no longer supported as of Jena 4.x

See Also:

• Constant Field Values

NO_AUTO_LOGGING_CONFIGURATION

@Deprecated
public static final String NO_AUTO_LOGGING_CONFIGURATION

Deprecated.

Constant for the special value used with the PARAM_LOGGING parameter to indicate that the user code will manage configuration of logging. This is also the default value when that parameter is not set.

See Also:

• Constant Field Values

PARAM_CONFIG

public static final String PARAM_CONFIG

Constant for the connection URL parameter used to set the path to a Java properties file used to provide additional connection parameters external to the URL. This is useful when you want to have a single connection string and pick up different configurations depending on where the driver is used.

Just like the PARAM_LOGGING parameter the file system is searched before the class path. Also note that this is the first parameter that is honored so settings present in the properties file may be overridden by those explicitly provided in the connection URL or those given in the Properties object passed to the Driver.connect(String, Properties) method.

If you specify this parameter in both the connection URL and the Properties object then the latter takes precedence and the former is ignored. It is also important to note that this is not transitively resolved i.e. if the referenced property file includes a config parameter it does not result in a further properties file/files being loaded.

See Also:

• Constant Field Values

Constructor Details

JenaDriver

public JenaDriver(int majorVer,
 int minorVer,
 String prefix)

Creates a new driver

Parameters:

majorVer - Major Version

minorVer - Minor Version

prefix - Implementation specific prefix which must end with a colon

Method Details

acceptsURL

public boolean acceptsURL(String url)

Specified by:

acceptsURL in interface Driver

connect

public final Connection connect(String url,
 Properties props)
                         throws SQLException

Specified by:

connect in interface Driver

Throws:

SQLException

getMajorVersion

public int getMajorVersion()

Specified by:

getMajorVersion in interface Driver

getMinorVersion

public int getMinorVersion()

Specified by:

getMinorVersion in interface Driver

getPropertyInfo

public final DriverPropertyInfo[] getPropertyInfo(String url,
 Properties props)
                                           throws SQLException

Specified by:

getPropertyInfo in interface Driver

Throws:

SQLException

jdbcCompliant

public final boolean jdbcCompliant()

Returns that a Jena JDBC driver is not JDBC compliant since strict JDBC compliance requires support for SQL-92 and since we are using SPARQL we don't meet that criteria

Specified by:

jdbcCompliant in interface Driver

getParentLogger

public Logger getParentLogger()
                       throws SQLFeatureNotSupportedException

Specified by:

getParentLogger in interface Driver

Throws:

SQLFeatureNotSupportedException