org.rhq.core.db

Class DatabaseTypeFactory

java.lang.Object

org.rhq.core.db.DatabaseTypeFactory

public class DatabaseTypeFactory
extends Object

A factory class that creates DatabaseType objects based on the database being connected to. This should be the only class (or at least one of the very few) that actually has database-specific knowledge coded into it.

Method Summary

Methods

Modifier and Type	Method and Description
static void	clearDatabaseTypeCache() By default, this factory will remember what DatabaseType is associated with a specific connection class type.
static Connection	getConnection(Context context, String datasource) Given a context and a JNDI datasource name, this will lookup within that context to find the named datasource.
static DatabaseType	getDatabaseType(Connection conn) Given a Connection object, this method returns its associated DatabaseType.
static DatabaseType	getDatabaseType(Context context, String datasource) Convenience method that gives you the DatabaseType given a context and datasource.
static DatabaseType	getDefaultDatabaseType() This is the getter of a get/set convenience mechanism for storing and retrieving the active database type.
static boolean	isH2(Connection c) Is the database H2?
static boolean	isH2(DatabaseType type) Determines if the given type refers to an H2 database.
static boolean	isOracle(Connection c) Is the database Oracle?
static boolean	isOracle(DatabaseType type) Determines if the given type refers to an Oracle database.
static boolean	isPostgres(Connection c) Is the database PostgreSQL?
static boolean	isPostgres(DatabaseType type) Determines if the given type refers to a Postgres database.
static boolean	isSQLServer(Connection c) Is the database SQL Server?
static boolean	isSQLServer(DatabaseType type) Determines if the given type refers to an SQL Server database.
static String	loadJdbcDriver(String jdbc_url) Given a JDBC URL, this will attempt to load in the JDBC driver class that will be needed to connect to the database via that URL and will return that driver class name.
static void	setDefaultDatabaseType(DatabaseType databaseType) This is the setter of a get/set convenience mechanism for storing and retrieving the active database type.

Methods inherited from class java.lang.Object

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

Method Detail

clearDatabaseTypeCache

public static void clearDatabaseTypeCache()

By default, this factory will remember what DatabaseType is associated with a specific connection class type. However, if you change the JDBC URL, its possible that this will also change the database type the connection class type should be associated with (i.e. the URL may point to a different version of the same vendor's database). If you change the JDBC URL, you should call this method to clear the cache, thus enabling the factory to re-check the connection metadata to associate a new database type with the connection class type.

getDatabaseType

public static DatabaseType getDatabaseType(Context context,
                           String datasource)
                                    throws Exception

Convenience method that gives you the DatabaseType given a context and datasource. This is a combination of getDatabaseType(Context, String) and getDatabaseType(Connection).

Parameters:

context - the context where the datasource can be found

datasource - the name of the datasource within the given context

Returns:

the DatabaseType of the type of database behind the data source

Throws:

Exception - if cannot find the datasource in the given context or the connection cannot be created or if cannot determine what database the connection is connected to

getConnection

public static Connection getConnection(Context context,
                       String datasource)
                                throws Exception

Given a context and a JNDI datasource name, this will lookup within that context to find the named datasource. A connection to that datasource will be created and returned - with the intent that the connection will be passed to getDatabaseType(Connection) to create a DatabaseType.

Parameters:

context - the context where the datasource can be found

datasource - the name of the datasource within the given context

Returns:

a connection to the given datasource

Throws:

Exception - if cannot find the datasource in the given context or the connection cannot be created

getDatabaseType

public static DatabaseType getDatabaseType(Connection conn)
                                    throws Exception

Given a Connection object, this method returns its associated DatabaseType.

Parameters:

conn -

Returns:

the DatabaseType that the connection is connected to

Throws:

Exception - if cannot determine what database the connection is connected to

getDefaultDatabaseType

public static DatabaseType getDefaultDatabaseType()

This is the getter of a get/set convenience mechanism for storing and retrieving the active database type. Not a true singleton but typically the value will not change as the underlying db is typically not going to change at runtime.

Returns:

The current DatabaseType or null if not yet set.

setDefaultDatabaseType

public static void setDefaultDatabaseType(DatabaseType databaseType)

This is the setter of a get/set convenience mechanism for storing and retrieving the active database type. Typically called one time when the dbType is established. Not a true singleton but typically the value will not change as the underlying db is typically not going to change.

loadJdbcDriver

public static String loadJdbcDriver(String jdbc_url)

Given a JDBC URL, this will attempt to load in the JDBC driver class that will be needed to connect to the database via that URL and will return that driver class name. If the driver class could not be loaded, null will be returned - in which case attempting to connect to the database with the given URL will probably fail.

Parameters:

jdbc_url - a connection URL to the database

Returns:

the driver class that was attempted to have been loaded

isPostgres

public static boolean isPostgres(Connection c)
                          throws Exception

Is the database PostgreSQL?

Parameters:

c - the connection to the database

Returns:

true if the connection is talking to a Postgres database

Throws:

Exception

isPostgres

public static boolean isPostgres(DatabaseType type)

Determines if the given type refers to a Postgres database.

Parameters:

type -

Returns:

true if the type is a Postgres database

isOracle

public static boolean isOracle(Connection c)
                        throws Exception

Is the database Oracle?

Parameters:

c - the connection to the database

Returns:

true if the connection is talking to an Oracle database

Throws:

Exception

isOracle

public static boolean isOracle(DatabaseType type)

Determines if the given type refers to an Oracle database.

Parameters:

type -

Returns:

true if the type is an Oracle database

isH2

public static boolean isH2(Connection c)
                    throws Exception

Is the database H2?

Parameters:

c - the connection to the database

Returns:

true if the connection is talking to an H2 database

Throws:

Exception

isH2

public static boolean isH2(DatabaseType type)

Determines if the given type refers to an H2 database.

Parameters:

type -

Returns:

true if the type is an H2 database

isSQLServer

public static boolean isSQLServer(Connection c)
                           throws Exception

Is the database SQL Server?

Parameters:

c - the connection to the database

Returns:

true if the connection is talking to an SQL Server database

Throws:

Exception

isSQLServer

public static boolean isSQLServer(DatabaseType type)

Determines if the given type refers to an SQL Server database.

Parameters:

type -

Returns:

true if the type is an SQL Server database