com.lutris.appserver.server.sql
Interface DatabaseManager

public interface DatabaseManager

The database management object interface. This class implementing this interface manages the database connections for one application.

Version:

$Revision: 1.1 $

Author:

Paul Morgan

Field Summary

static boolean

debug Flag to enable debug logging of queries and transactions.

Method Summary

DBConnection	allocateConnection() Allocate a connection to the default logical database.
DBConnection	allocateConnection(java.lang.String dbName) Allocate a connection to the specified logic database.
ObjectId	allocateObjectId() Allocate an object id from the specified logical database.
ObjectId	allocateObjectId(java.lang.String dbName) Allocate an object id from the specified logical database.
void	checkOId(ObjectId oid) Check does oid belong to Object id's range [minOId, currentOId] for default database
void	checkOId(java.lang.String dbName, ObjectId oid) Check does oid belong to Object id's range [minOId, currentOId]
DBQuery	createQuery() Create a query object for the default logical database.
DBQuery	createQuery(java.lang.String dbName) Create a query object for the specified logical database.
DBTransaction	createTransaction() Create a transaction object for the default logical database.
DBTransaction	createTransaction(java.lang.String dbName) Create a transaction object for the specified logical database.
LogicalDatabase	findLogicalDatabase(java.lang.String dbName)
int	getActiveConnectionCount(java.lang.String dbName) Returns the number of currently active connections for the supplied logical database name.
com.lutris.util.Config	getConfig() Return main configuration class
java.lang.String	getDefaultDB() Return default database name (given in config file)
java.lang.String[]	getLogicalDatabaseNames() Returns the list of managed logical databases.
int	getMaxConnectionCount(java.lang.String dbName) Returns the maximum number of concurent connections that existed at any time since this object was created, or resetMaxConnectionCount() was called.
java.util.Date	getMaxConnectionCountDate(java.lang.String dbName) Returns the time when the maximum refered to by maxConnectionCount() occured.
long	getRequestCount(java.lang.String dbName) Returns the number of requests made to the database since startup time.
java.lang.String	getType(java.lang.String dbName) Returns a description of the logical database type.
java.lang.String	logicalDatabaseType() Return a logical database type for the default logical database.
java.lang.String	logicalDatabaseType(java.lang.String dbName) Return a logical database type for the default logical database.
void	resetMaxConnectionCount(java.lang.String dbName) Reset the maximum connection count.
void	setDefaultDatabase(java.lang.String dbName) Set the default logical database.
void	shutdown() Shutdown the database manager.

Field Detail

debug

public static final boolean debug

Flag to enable debug logging of queries and transactions.

See Also:

Constant Field Values

Method Detail

getConfig

public com.lutris.util.Config getConfig()

Return main configuration class

Returns:

main configuration class.

allocateConnection

public DBConnection allocateConnection(java.lang.String dbName)
                                throws DatabaseManagerException,
                                       java.sql.SQLException

Allocate a connection to the specified logic database. The connection should be returned to the pool by calling its release() function. A thread will wait if no connections are available. Interupted exceptions are converted to errors.

Parameters:

dbName - Logical name of the database to allocate a connection to.

Returns:

The allocated connection object.

Throws:

DatabaseManagerException - If a nonexistent logical database name is supplied.

java.sql.SQLException - If a SQL error occures.

allocateConnection

public DBConnection allocateConnection()
                                throws DatabaseManagerException,
                                       java.sql.SQLException

Allocate a connection to the default logical database. The connection should be returned to the pool by calling its release() function. A thread will wait if no connections are available. Interupted exceptions are converted to errors.

Returns:

The allocated connection object.

Throws:

DatabaseManagerException - If a nonexistent default logical database name is supplied.

java.sql.SQLException - If a SQL error occures.

See Also:

setDefaultDatabase(java.lang.String)

allocateObjectId

public ObjectId allocateObjectId(java.lang.String dbName)
                          throws DatabaseManagerException,
                                 ObjectIdException

Allocate an object id from the specified logical database.

Parameters:

dbName - Logical name of the database from which to obtain an object id.

Returns:

The allocated unique OID

Throws:

DatabaseManagerException - If a nonexistent logical database name is supplied.

ObjectIdException - If a problem (e.g. SQL error) occured in obtaining the OID.

allocateObjectId

public ObjectId allocateObjectId()
                          throws DatabaseManagerException,
                                 ObjectIdException

Allocate an object id from the specified logical database.

Returns:

The allocated connection object.

Throws:

DatabaseManagerException - If a nonexistent default logical database has been set.

ObjectIdException - If a problem (e.g. SQL error) occured in obtaining the OID.

See Also:

setDefaultDatabase(java.lang.String)

checkOId

public void checkOId(java.lang.String dbName,
                     ObjectId oid)
              throws DatabaseManagerException,
                     ObjectIdException

Check does oid belong to Object id's range [minOId, currentOId]

Parameters:

dbName - Logical name of the database from which to check an object id.

oid - oid which will be checked.

Throws:

DatabaseManagerException - If a nonexistent logical database name is supplied.

ObjectIdException - If a oid does't belong to range.

checkOId

public void checkOId(ObjectId oid)
              throws DatabaseManagerException,
                     ObjectIdException

Check does oid belong to Object id's range [minOId, currentOId] for default database

Parameters:

oid - oid which will be checked.

Throws:

DatabaseManagerException - If a nonexistent default logical database has been set.

ObjectIdException - If a oid does't belong to range.

createTransaction

public DBTransaction createTransaction(java.lang.String dbName)
                                throws DatabaseManagerException,
                                       java.sql.SQLException

Create a transaction object for the specified logical database.

Parameters:

dbName - Logical name of the database from which to obtain a transaction.

Returns:

The transaction

Throws:

DatabaseManagerException - If a nonexistent or invalid logical database name is supplied.

java.sql.SQLException - If a problem occured creating the transaction.

createTransaction

public DBTransaction createTransaction()
                                throws DatabaseManagerException,
                                       java.sql.SQLException

Create a transaction object for the default logical database.

Returns:

The transaction

Throws:

DatabaseManagerException - If a nonexistent default logical database has been set.

java.sql.SQLException - If a problem occured creating the transaction.

See Also:

setDefaultDatabase(java.lang.String)

createQuery

public DBQuery createQuery(java.lang.String dbName)
                    throws DatabaseManagerException,
                           java.sql.SQLException

Create a query object for the specified logical database.

Parameters:

dbName - Logical name of the database from which to obtain a query.

Returns:

The query

Throws:

DatabaseManagerException - If a nonexistent or invalid logical database name is supplied.

java.sql.SQLException - If a problem occured creating the query.

createQuery

public DBQuery createQuery()
                    throws DatabaseManagerException,
                           java.sql.SQLException

Create a query object for the default logical database.

Returns:

The query

Throws:

DatabaseManagerException - If a nonexistent default logical database has been set.

java.sql.SQLException - If a problem occured creating the query.

See Also:

setDefaultDatabase(java.lang.String)

logicalDatabaseType

public java.lang.String logicalDatabaseType(java.lang.String dbName)
                                     throws DatabaseManagerException,
                                            java.sql.SQLException

Return a logical database type for the default logical database.

Parameters:

dbName - Logical name of the database from which to obtain a query.

Returns:

logical database type

Throws:

DatabaseManagerException - If a nonexistent default logical database has been set.

java.sql.SQLException - If a problem occured creating the query.

See Also:

setDefaultDatabase(java.lang.String)

logicalDatabaseType

public java.lang.String logicalDatabaseType()
                                     throws DatabaseManagerException,
                                            java.sql.SQLException

Return a logical database type for the default logical database.

Returns:

logical database type

Throws:

DatabaseManagerException - If a nonexistent default logical database has been set.

java.sql.SQLException - If a problem occured creating the query.

See Also:

setDefaultDatabase(java.lang.String)

setDefaultDatabase

public void setDefaultDatabase(java.lang.String dbName)
                        throws DatabaseManagerException

Set the default logical database. This should be used with caution, but it makes allocating connections easier.

Parameters:

dbName - The default logical dabase name.

Throws:

DatabaseManagerException - If a nonexistent or illegal logical database name is supplied.

getDefaultDB

public java.lang.String getDefaultDB()

Return default database name (given in config file)

Returns:

default database name

shutdown

public void shutdown()

Shutdown the database manager. All logical databases will be shutdown and all connection closed.

getLogicalDatabaseNames

public java.lang.String[] getLogicalDatabaseNames()

Returns the list of managed logical databases.

Returns:

List of logical database names.

getType

public java.lang.String getType(java.lang.String dbName)
                         throws DatabaseManagerException

Returns a description of the logical database type.

Parameters:

dbName - The logical database name.

Returns:

A text description of the logical database type.

Throws:

DatabaseManagerException - If a nonexistent logical database name is supplied.

getRequestCount

public long getRequestCount(java.lang.String dbName)
                     throws DatabaseManagerException

Returns the number of requests made to the database since startup time.

Parameters:

dbName - The logical database name.

Returns:

The number of database requests since the server started.

Throws:

DatabaseManagerException - If a nonexistent logical database name is supplied.

getActiveConnectionCount

public int getActiveConnectionCount(java.lang.String dbName)
                             throws DatabaseManagerException

Returns the number of currently active connections for the supplied logical database name. If not implemented, then -1 is returned.

Parameters:

dbName - The logical database name.

Returns:

The number of currently active connections.

Throws:

DatabaseManagerException - If a nonexistent logical database name is supplied.

getMaxConnectionCount

public int getMaxConnectionCount(java.lang.String dbName)
                          throws DatabaseManagerException

Returns the maximum number of concurent connections that existed at any time since this object was created, or resetMaxConnectionCount() was called. This is a historical highwater mark. If not implemented, then -1 is returned.

Parameters:

dbName - The logical database name.

Returns:

The highwater mark for number of connections, or -1.

Throws:

DatabaseManagerException - If a nonexistent logical database name is supplied.

getMaxConnectionCountDate

public java.util.Date getMaxConnectionCountDate(java.lang.String dbName)
                                         throws DatabaseManagerException

Returns the time when the maximum refered to by maxConnectionCount() occured. If not implemented, then null is returned.

Parameters:

dbName - The logical database name.

Returns:

The Date of when the maximum number of connections occured.

Throws:

DatabaseManagerException - If a nonexistent logical database name is supplied.

resetMaxConnectionCount

public void resetMaxConnectionCount(java.lang.String dbName)
                             throws DatabaseManagerException

Reset the maximum connection count. See maxConnectionCount(). The highwater mark should be reset to the current number of connections.

Parameters:

dbName - The logical database name.

Throws:

DatabaseManagerException - If a nonexistent logical database name is supplied.

findLogicalDatabase

public LogicalDatabase findLogicalDatabase(java.lang.String dbName)
                                    throws DatabaseManagerException

Throws:

DatabaseManagerException