de.fuberlin.wiwiss.ng4j.db
Class QuadDB

java.lang.Object
  de.fuberlin.wiwiss.ng4j.db.QuadDB

public class QuadDB
extends Object

Database persistence for a set of Quads and a set of graph names, with a Node based interface. The class manages two collections of objects: a set of quads, and a set of graph names. The latter is needed because we want to support empty graphs.

All operations but insert(com.hp.hpl.jena.graph.Node, com.hp.hpl.jena.graph.Node, com.hp.hpl.jena.graph.Node, com.hp.hpl.jena.graph.Node) allow Node.ANY wildcards.

The implementation is na•ve: a graphs table and a quads table. A table prefix can be supplied in order to support multiple QuadDBs in a single database.

TODO: Factor out DB-specific stuff, e.g. table creation.

Author:

Richard Cyganiak (richard@cyganiak.de)

Field Summary

static int	HSQL_TYPE
static int	MYSQL_TYPE
static int	POSTGRESQL_TYPE

Constructor Summary

QuadDB(Connection connection, String tablePrefix)

Method Summary

void	close()
boolean	containsGraphName(Node graphName)
int	count()
int	countGraphNames()
void	createTables()
void	delete(Node g, Node s, Node p, Node o)
void	deleteGraphName(Node graphName)
void	deleteTables()
Iterator	find(Node g, Node s, Node p, Node o)
void	insert(Node g, Node s, Node p, Node o)
void	insertGraphName(Node graphName)
Iterator	listGraphNames()
boolean	tablesExist()

Methods inherited from class java.lang.Object

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

Field Detail

HSQL_TYPE

public static final int HSQL_TYPE

See Also:

Constant Field Values

MYSQL_TYPE

public static final int MYSQL_TYPE

See Also:

Constant Field Values

POSTGRESQL_TYPE

public static final int POSTGRESQL_TYPE

See Also:

Constant Field Values

Constructor Detail

QuadDB

public QuadDB(Connection connection,
              String tablePrefix)

Method Detail

insert

public void insert(Node g,
                   Node s,
                   Node p,
                   Node o)

delete

public void delete(Node g,
                   Node s,
                   Node p,
                   Node o)

find

public Iterator find(Node g,
                     Node s,
                     Node p,
                     Node o)

count

public int count()

insertGraphName

public void insertGraphName(Node graphName)

deleteGraphName

public void deleteGraphName(Node graphName)

containsGraphName

public boolean containsGraphName(Node graphName)

listGraphNames

public Iterator listGraphNames()

countGraphNames

public int countGraphNames()

createTables

public void createTables()

deleteTables

public void deleteTables()

tablesExist

public boolean tablesExist()

close

public void close()