com.hp.hpl.jena.db
Class DBConnection

java.lang.Object
  com.hp.hpl.jena.db.DBConnection

All Implemented Interfaces:

IDBConnection

public class DBConnection
extends java.lang.Object
implements IDBConnection

Encapsulate the specification of a jdbc connection. This is mostly used to simplify the calling pattern for ModelRDB factory methods.

Version:

$Revision: 1.1 $

Author:

csayers (based in part on the jena 1 implementation by der).

Constructor Summary

DBConnection(java.sql.Connection connection, java.lang.String databaseType)
Create a connection specification that just wraps up an existing database connection.

DBConnection(java.lang.String url, java.lang.String user, java.lang.String password, java.lang.String databaseType)
Create a connection specification based on jdbc address and appropriate authentication information.

Method Summary

void	cleanDB() Clear all RDF information from the database.
void	close() Close the jdbc connection
boolean	containsDefaultModel() Test if a default model is contained in the database.
boolean	containsModel(java.lang.String name) Test if a given model is contained in the database.
com.hp.hpl.jena.util.iterator.ExtendedIterator<java.lang.String>	getAllModelNames() Retrieve a list of all models in the database
java.sql.Connection	getConnection() Return the jdbc connection or null if we no longer have access to a connection.
Model	getDatabaseProperties() Returns a Jena Model containing database properties.
java.lang.String	getDatabaseType() Get the database type.
Model	getDefaultModelProperties() Retrieve a default set of model customization properties.
com.hp.hpl.jena.db.impl.IRDBDriver	getDriver() Get the database-specific driver For this to work, it needs to know the type of database being used.
boolean	isFormatOK() Return true if the database seems to be formated for RDF storage.
void	setDatabaseProperties(Model dbProperties) Sets database-specific properties.
void	setDatabaseType(java.lang.String databaseType) Set the database type manually.
void	setDriver(com.hp.hpl.jena.db.impl.IRDBDriver driver) Set the IRDBDriver to use for this connection.

Methods inherited from class java.lang.Object

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

Constructor Detail

DBConnection

public DBConnection(java.lang.String url,
                    java.lang.String user,
                    java.lang.String password,
                    java.lang.String databaseType)

Create a connection specification based on jdbc address and appropriate authentication information.

Parameters:

url - the jdbc url for the database, note that the format of this is database dependent and that the appropriate jdbc driver will need to be specified via the standard pattern

     Class.forName("my.sql.driver");
 

user - the user name to log on with

password - the password corresponding to this user

databaseType - the type of database to which we are connecting.

Since:

Jena 2.0

DBConnection

public DBConnection(java.sql.Connection connection,
                    java.lang.String databaseType)

Create a connection specification that just wraps up an existing database connection.

Parameters:

connection - the open jdbc connection to use

databaseType - the type of database to which we are connecting.

Since:

Jena 2.0

Method Detail

getConnection

public java.sql.Connection getConnection()
                                  throws java.sql.SQLException

Description copied from interface: IDBConnection

Return the jdbc connection or null if we no longer have access to a connection.

Specified by:

getConnection in interface IDBConnection

Throws:

java.sql.SQLException

close

public void close()
           throws java.sql.SQLException

Description copied from interface: IDBConnection

Close the jdbc connection

Specified by:

close in interface IDBConnection

Throws:

java.sql.SQLException

cleanDB

public void cleanDB()
             throws java.sql.SQLException

Description copied from interface: IDBConnection

Clear all RDF information from the database. All the Jena RDF tables are dropped. This wipes all the information stored by Jena from the database. Obviously should be used with care. The next atempt to open a DB model will (attempt to) recreate the Jena tables.

Specified by:

cleanDB in interface IDBConnection

Throws:

java.sql.SQLException

isFormatOK

public boolean isFormatOK()

Description copied from interface: IDBConnection

Return true if the database seems to be formated for RDF storage. This is not an integrity check this is simply a flag recording that a base level table exists. Any access errors are treated as the database not being formated.

Specified by:

isFormatOK in interface IDBConnection

setDatabaseProperties

public void setDatabaseProperties(Model dbProperties)
                           throws RDFRDBException

Description copied from interface: IDBConnection

Sets database-specific properties.

These properties may only be set before the first Model has been stored in the database. After that point, the database structure is frozen.

Use these properties to optionally customize the database - this won't change the results you see when using the graph interface, but it may alter the speed with which you get them or the space required by the database.

The properties must form a complete and consistent set. The easist way to get a complete and consistent set is to call getDatabaseProperties, modify the returned model, and then use that as an argument in the call to setDatabaseProperties.

Note that some implementations may choose to delay actually peforming the formatting operation until at least one Graph is constructed in the database. Consequently, a successful return from this call does not necessarily guarantee that the database properties were set correctly.

Specified by:

setDatabaseProperties in interface IDBConnection

Parameters:

dbProperties - is a Model describing the database parameters

Throws:

RDFRDBException

getDatabaseProperties

public Model getDatabaseProperties()
                            throws RDFRDBException

Description copied from interface: IDBConnection

Returns a Jena Model containing database properties.

These describe the optimization/layout for the database.

If the database has not been formatted, then a default set of properties is returned. Otherwise the actual properties are returned.

The returned Model is a copy, modifying it will have no effect on the database. (Use setDatabaseProperties to make changes).

Specified by:

getDatabaseProperties in interface IDBConnection

Throws:

RDFRDBException

getDefaultModelProperties

public Model getDefaultModelProperties()
                                throws RDFRDBException

Description copied from interface: IDBConnection

Retrieve a default set of model customization properties. The returned default set of properties is suitable for use in a call to ModelRDB.create(..., modelProperties);

Specified by:

getDefaultModelProperties in interface IDBConnection

Returns:

Model containing default properties

Throws:

RDFRDBException

getAllModelNames

public com.hp.hpl.jena.util.iterator.ExtendedIterator<java.lang.String> getAllModelNames()
                                                                                  throws RDFRDBException

Description copied from interface: IDBConnection

Retrieve a list of all models in the database

Specified by:

getAllModelNames in interface IDBConnection

Returns:

Iterator over String names for graphs.

Throws:

RDFRDBException

containsModel

public boolean containsModel(java.lang.String name)
                      throws RDFRDBException

Description copied from interface: IDBConnection

Test if a given model is contained in the database.

Specified by:

containsModel in interface IDBConnection

Parameters:

name - the name of a model which may be in the database

Returns:

Boolean true if the model is contained in the database

Throws:

RDFRDBException

containsDefaultModel

public boolean containsDefaultModel()
                             throws RDFRDBException

Description copied from interface: IDBConnection

Test if a default model is contained in the database. A default model is a model for which no specific name was specified. (One that was created by calling ModelRDB.createModel without specifying a name).

Specified by:

containsDefaultModel in interface IDBConnection

Returns:

Boolean true if the model is contained in the database

Throws:

RDFRDBException

setDatabaseType

public void setDatabaseType(java.lang.String databaseType)

Description copied from interface: IDBConnection

Set the database type manually.

This is not for public use (it is preferable to specify it in the constructor) - included here to handle older code, which didn't use the new constructor.

Specified by:

setDatabaseType in interface IDBConnection

getDatabaseType

public java.lang.String getDatabaseType()

Description copied from interface: IDBConnection

Get the database type.

Specified by:

getDatabaseType in interface IDBConnection

Returns:

String database type, or null if unset

getDriver

public com.hp.hpl.jena.db.impl.IRDBDriver getDriver()
                                             throws RDFRDBException

Description copied from interface: IDBConnection

Get the database-specific driver For this to work, it needs to know the type of database being used. That may be specified in the constructor (preferred) or done later by using the setDatabaseType method (for backward compatability).

Specified by:

getDriver in interface IDBConnection

Throws:

RDFRDBException

setDriver

public void setDriver(com.hp.hpl.jena.db.impl.IRDBDriver driver)

Description copied from interface: IDBConnection

Set the IRDBDriver to use for this connection. Useful to enable external drivers to be registered outside of the standard driver package.

Specified by:

setDriver in interface IDBConnection