uk.ac.ed.epcc.webapp.jdbc

Class WrappedDatabaseService

java.lang.Object

uk.ac.ed.epcc.webapp.jdbc.WrappedDatabaseService

All Implemented Interfaces:

AppContextCleanup, AppContextService<DatabaseService>, Contexed, CloseRegistry, DatabaseService

public class WrappedDatabaseService
extends java.lang.Object
implements DatabaseService

A DatabaseService wrapper that can beused to generate a tabe showing the current active connections

Field Summary

Fields inherited from interface uk.ac.ed.epcc.webapp.jdbc.DatabaseService

LOG_INSERT_FEATURE, LOG_QUERY_FEATURE, LOG_UPDATE, USE_SQL_DISTICT_FEATURE

Constructor Summary

Constructors

Constructor and Description
WrappedDatabaseService(AppContext conn)
WrappedDatabaseService(DatabaseService inner, java.lang.String id)

Method Summary

Modifier and Type	Method and Description
static void	add(WrappedDatabaseService serv)
void	addClosable(java.lang.AutoCloseable c)
void	cleanup() AppContext is being closed.
void	closeRetainedClosables()
void	commitTransaction() flush changes since start of last commit.
java.util.Map<java.lang.String,java.lang.Object>	getConnectionAttributes() get a map of information about the connection
AppContext	getContext()
SQLContext	getSQLContext() get SQLContext using the default ConfigService
SQLContext	getSQLContext(java.lang.String tag) get alternative database SQLContext If the tag is null it returns the same SQLContext as DatabaseService.getSQLContext().
SQLContext	getSQLContext(java.lang.String tag, java.util.Properties config_props) get a {SQLContext} based on properties
static Table	getStatusTable()
java.lang.Class<? super DatabaseService>	getType() Returns the type of service the class should be registered under.
void	handleError(java.lang.String message, java.sql.SQLException e) Handle an unexpected database exception.
boolean	inTransaction() Are we already in a transaction
void	logError(java.lang.String message, java.sql.SQLException e) handle an SQLException directly.
static void	remove(WrappedDatabaseService serv)
void	removeClosable(java.lang.AutoCloseable c)
void	rollbackTransaction() Abort changes since start or last commit
void	startTransaction() Start a database transaction Transactions cannot be nested so use DatabaseService.inTransaction() if possible doubt.
void	stopTransaction() finish transaction (includes commit).
int	transactionStage() returns the number of times DatabaseService.commitTransaction() has been called since the last transaction start.

Methods inherited from class java.lang.Object

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

Constructor Detail

WrappedDatabaseService

public WrappedDatabaseService(AppContext conn)

Parameters:

conn -

WrappedDatabaseService

public WrappedDatabaseService(DatabaseService inner,
                              java.lang.String id)

Method Detail

add

public static void add(WrappedDatabaseService serv)

remove

public static void remove(WrappedDatabaseService serv)

getStatusTable

public static Table getStatusTable()

getContext

public AppContext getContext()

Specified by:

getContext in interface Contexed

getType

public java.lang.Class<? super DatabaseService> getType()

Description copied from interface: AppContextService

Returns the type of service the class should be registered under.

Specified by:

getType in interface AppContextService<DatabaseService>

Returns:

registration type

cleanup

public void cleanup()

Description copied from interface: AppContextCleanup

AppContext is being closed. Only use this for cleanup that can't be handled by normal garbage collection or for state which is never returned by reference.

Specified by:

cleanup in interface AppContextCleanup

addClosable

public void addClosable(java.lang.AutoCloseable c)

Specified by:

addClosable in interface CloseRegistry

removeClosable

public void removeClosable(java.lang.AutoCloseable c)

Specified by:

removeClosable in interface CloseRegistry

getSQLContext

public SQLContext getSQLContext(java.lang.String tag,
                                java.util.Properties config_props)
                         throws java.sql.SQLException

Description copied from interface: DatabaseService

get a {SQLContext} based on properties

Specified by:

getSQLContext in interface DatabaseService

Returns:

SQLContext

Throws:

java.sql.SQLException

getSQLContext

public SQLContext getSQLContext()
                         throws java.sql.SQLException

Description copied from interface: DatabaseService

get SQLContext using the default ConfigService

Specified by:

getSQLContext in interface DatabaseService

Returns:

SQLContext to database

Throws:

java.sql.SQLException

getSQLContext

public SQLContext getSQLContext(java.lang.String tag)
                         throws java.sql.SQLException

Description copied from interface: DatabaseService

get alternative database SQLContext If the tag is null it returns the same SQLContext as DatabaseService.getSQLContext().

Specified by:

getSQLContext in interface DatabaseService

Returns:

Connection to database

Throws:

java.sql.SQLException

inTransaction

public boolean inTransaction()

Description copied from interface: DatabaseService

Are we already in a transaction

Specified by:

inTransaction in interface DatabaseService

Returns:

boolean

transactionStage

public int transactionStage()

Description copied from interface: DatabaseService

returns the number of times DatabaseService.commitTransaction() has been called since the last transaction start. If this returns 0 then a roll-back will return to the state at DatabaseService.startTransaction() if greater than zero there have been intermediate commits. To aid in testing the value is not reset to zero until the next call to DatabaseService.startTransaction()

Specified by:

transactionStage in interface DatabaseService

Returns:

int

startTransaction

public void startTransaction()

Description copied from interface: DatabaseService

Start a database transaction Transactions cannot be nested so use DatabaseService.inTransaction() if possible doubt.

Specified by:

startTransaction in interface DatabaseService

rollbackTransaction

public void rollbackTransaction()

Description copied from interface: DatabaseService

Abort changes since start or last commit

Specified by:

rollbackTransaction in interface DatabaseService

commitTransaction

public void commitTransaction()

Description copied from interface: DatabaseService

flush changes since start of last commit. Unlike the commit method of a Connection this is a NOP if not in a transaction. Call before an operation that modifies external state as these won't roll-back. However probably better to defer the external state change using the CleanupService unless the transaction phases all make sense in their own right.

Specified by:

commitTransaction in interface DatabaseService

stopTransaction

public void stopTransaction()

Description copied from interface: DatabaseService

finish transaction (includes commit).

Specified by:

stopTransaction in interface DatabaseService

handleError

public void handleError(java.lang.String message,
                        java.sql.SQLException e)
                 throws DataFault

Description copied from interface: DatabaseService

Handle an unexpected database exception. Most of the time this will just re-throw the exception wrapped in a DataFault however this also allow special handing of certain classes of error such as SQLTransientExceptions

Specified by:

handleError in interface DatabaseService

Throws:

DataFault

logError

public void logError(java.lang.String message,
                     java.sql.SQLException e)

Description copied from interface: DatabaseService

handle an SQLException directly. Normally this will just log the error however this also allow special handing of certain classes of error such as SQLTransientExceptions

Specified by:

logError in interface DatabaseService

closeRetainedClosables

public void closeRetainedClosables()

Specified by:

closeRetainedClosables in interface CloseRegistry

getConnectionAttributes

public java.util.Map<java.lang.String,java.lang.Object> getConnectionAttributes()
                                                                         throws java.lang.Exception

Description copied from interface: DatabaseService

get a map of information about the connection

Specified by:

getConnectionAttributes in interface DatabaseService

Returns:

Throws:

java.lang.Exception