ParkNPark.middletier
Class ClientManagerImpl

java.lang.Object
  org.omg.PortableServer.Servant
      ParkNPark.interfaces.ClientManagerPOA
          ParkNPark.middletier.ClientManagerImpl

All Implemented Interfaces:

InvokeHandler, ClientManagerOperations

public class ClientManagerImpl
extends ClientManagerPOA

Server object that will manage communication between the client and the database.

Field Summary

protected PreparedStatement	checkDuplicate Statements used for duplicate message detection
protected String	clientHostname Client's hostname
protected int	clientID Client's ID used for fault-tolerance
protected Connection	conn Connection to the database
protected DatabaseManager	databaseManager Our database manager instance
protected static int	INTEGER_SIZE Size of an intger variable
protected byte[]	integerPadding Byte array used to pad integer variables
protected int	level Level that client is in
protected Logger	logger Our Logger instance
protected int	lot Lot that client is in
protected static int	MAX_ATTEMPTS Maximum number of attempts when trying to execute commends on database
protected PaddedVoid	paddedVoid PaddedVoid instance for padded void returns
protected static boolean	PRINT_LEVELS_STATUS
protected static boolean	PRINT_LOTS_STATUS Flags used to print out the status of lots and levels
protected int	replySize Size of replies
protected int	seq Client's current operation sequence number used for fault-tolerance
protected PreparedStatement	updateSequence

Constructor Summary

ClientManagerImpl(DatabaseManager databaseManager, int clientID, String clientHostname, Logger logger, int replySize)
Create a client manager for an existing client that will hold information specific to the client.

ClientManagerImpl(DatabaseManager databaseManager, String clientHostname, Logger logger, int replySize)
Create a client manager for a new client that will hold information specific to the client.

Method Summary

protected boolean	alreadyCompleted(int seq) Checks if the current client request has already been completed.
void	closeClientManager() Closes the client manager and frees server resources associated with it, including the client manager's activation in the server's CORBA portable object adapter
PaddedIntegerSeq	enterLot(int seq, int lot) Moves the client's car into the lot with the given lot number and returns an array of level numbers that have available spaces
PaddedVoid	exitLot(int seq) Removes the client's car from the lot that it is currently in
PaddedInteger	getClientID() Returns the client's ID, which can be used in the client manager factory's getExistingClientManager() method
PaddedInteger	getCurrentLevel() Returns the car's current level number
PaddedIntegerSeq	getLots() Returns an array of valid lot numbers in the system, sorted by the lot number in ascending order
PaddedInteger	getMaxLevel() Returns the top level number of the car's current parking lot
PaddedInteger	getMinLevel() Returns the bottom level number of the car's current parking lot
PaddedIntegerSeq	getOtherLotAvailability(int lot) Returns an array of other lots that have availability, sorted by lot distance such that closer lots are listed first
PaddedInteger	moveDownLevel(int seq) Moves the car from its present level to the level beneath it
PaddedInteger	moveUpLevel(int seq) Moves the car from its present level to the level above it
protected PaddedInteger	padInteger(int value) Pad the integer in order to make it comply with the reply size of the analysis
protected PaddedIntegerSeq	padIntegerArray(int[] value) Pad the integer array in order to make it comply with the reply size of the analysis
protected PaddedVoid	padVoid() Pad the void in order to make it comply with the reply size of the analysis
protected void	printLevelsStatus(String message, int seq) Print the status of all the levels in the current lot
protected void	printLotsStatus(String message, int seq) Print the status of all the lots
protected void	setupDatabaseConn() Set up the database connection
protected void	setupProbes(String clientHostname, Logger logger, int replySize) Setup probes for real-time analysis
protected void	updateClientData(int seq, int lot, int level) Updates the client table, which is used for duplicate detection.

Methods inherited from class ParkNPark.interfaces.ClientManagerPOA

_all_interfaces, _invoke, _this, _this

Methods inherited from class org.omg.PortableServer.Servant

_default_POA, _get_delegate, _get_interface_def, _is_a, _non_existent, _object_id, _orb, _poa, _set_delegate, _this_object, _this_object

Methods inherited from class java.lang.Object

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

Field Detail

MAX_ATTEMPTS

protected static final int MAX_ATTEMPTS

Maximum number of attempts when trying to execute commends on database

See Also:

Constant Field Values

INTEGER_SIZE

protected static int INTEGER_SIZE

Size of an intger variable

integerPadding

protected byte[] integerPadding

Byte array used to pad integer variables

paddedVoid

protected PaddedVoid paddedVoid

PaddedVoid instance for padded void returns

PRINT_LOTS_STATUS

protected static final boolean PRINT_LOTS_STATUS

Flags used to print out the status of lots and levels

See Also:

Constant Field Values

PRINT_LEVELS_STATUS

protected static final boolean PRINT_LEVELS_STATUS

See Also:

Constant Field Values

databaseManager

protected DatabaseManager databaseManager

Our database manager instance

clientID

protected int clientID

Client's ID used for fault-tolerance

seq

protected int seq

Client's current operation sequence number used for fault-tolerance

lot

protected int lot

Lot that client is in

level

protected int level

Level that client is in

conn

protected Connection conn

Connection to the database

checkDuplicate

protected PreparedStatement checkDuplicate

Statements used for duplicate message detection

updateSequence

protected PreparedStatement updateSequence

clientHostname

protected String clientHostname

Client's hostname

replySize

protected int replySize

Size of replies

logger

protected Logger logger

Our Logger instance

Constructor Detail

ClientManagerImpl

public ClientManagerImpl(DatabaseManager databaseManager,
                         int clientID,
                         String clientHostname,
                         Logger logger,
                         int replySize)
                  throws ServiceUnavailableException,
                         InvalidClientException

Create a client manager for an existing client that will hold information specific to the client.

Parameters:

databaseManager - The database manager to use in this client manager

clientID - The ID of the client to restore this ClientManager instance from

clientHostname - The hostname of the client

logger - The Logger object to log performance data to

replySize - The size of the method return values to use for the current test

Throws:

ServiceUnavailableException - Thrown when a database exception prevented the client manager from being created successfully

InvalidClientException - Thrown when the given client ID does not exist in the database

ClientManagerImpl

public ClientManagerImpl(DatabaseManager databaseManager,
                         String clientHostname,
                         Logger logger,
                         int replySize)
                  throws ServiceUnavailableException

Create a client manager for a new client that will hold information specific to the client.

Parameters:

databaseManager - The database manager to use in this client manager

clientHostname - The hostname of the client

logger - The Logger object to log performance data to

replySize - The size of the method return values to use for the current test

Throws:

ServiceUnavailableException - Thrown when a database exception prevented the client manager from being created successfully

Method Detail

setupDatabaseConn

protected void setupDatabaseConn()
                          throws ServiceUnavailableException

Set up the database connection

Throws:

ServiceUnavailableException - Thrown if a problem came up while connecting to the database server or setting it up after connecting

setupProbes

protected void setupProbes(String clientHostname,
                           Logger logger,
                           int replySize)

Setup probes for real-time analysis

Parameters:

clientHostname -

numClients -

interRequestTime -

replySize -

serverHostname -

closeClientManager

public void closeClientManager()
                        throws ServiceUnavailableException

Closes the client manager and frees server resources associated with it, including the client manager's activation in the server's CORBA portable object adapter

Throws:

ServiceUnavailableException - Thrown if the database cannot be contacted or if some other reason prevents the system from closing the client manager. The client manager remains open if this exception gets thrown

enterLot

public PaddedIntegerSeq enterLot(int seq,
                                 int lot)
                          throws AlreadyInLotException,
                                 LotNotFoundException,
                                 LotFullException,
                                 ServiceUnavailableException

Moves the client's car into the lot with the given lot number and returns an array of level numbers that have available spaces

Parameters:

seq - The latest sequence number of the client

lot - The lot number to enter

Returns:

An array of level numbers that have available spaces

Throws:

AlreadyInLotException - Thrown when the client's car is already in a lot

LotNotFoundException - Thrown if the given lot number is not known to the system

LotFullException - Thrown if the given lot is full

ServiceUnavailableException - Thrown if the database cannot be contacted or if some other reason prevents the car from entering the lot

exitLot

public PaddedVoid exitLot(int seq)
                   throws NotInLotException,
                          NotOnExitLevelException,
                          ServiceUnavailableException

Removes the client's car from the lot that it is currently in

Parameters:

seq - The latest sequence number of the client

Throws:

NotInLotException - Thrown if the car is not in a lot

NotOnExitLevelException - Thrown if the car is in a lot but is not on a permitted exit level

ServiceUnavailableException - Thrown if the database cannot be contacted or if some other reason prevents the car from exiting the lot

getClientID

public PaddedInteger getClientID()
                          throws ServiceUnavailableException

Returns the client's ID, which can be used in the client manager factory's getExistingClientManager() method

Returns:

The client's ID

Throws:

ServiceUnavailableException - Thrown when the log is closed and the server is shutting down

getCurrentLevel

public PaddedInteger getCurrentLevel()
                              throws NotInLotException,
                                     ServiceUnavailableException

Returns the car's current level number

Returns:

The car's current level number

Throws:

NotInLotException - Thrown if the car is not in a lot

ServiceUnavailableException - Thrown if the database cannot be contacted or if some other reason prevents the system from returning the car's current level

getLots

public PaddedIntegerSeq getLots()
                         throws ServiceUnavailableException

Returns an array of valid lot numbers in the system, sorted by the lot number in ascending order

Returns:

An array of valid lot numbers in the system

Throws:

ServiceUnavailableException - Thrown if the database cannot be contacted or if some other reason prevents the system from discovering the its defined lots

getMaxLevel

public PaddedInteger getMaxLevel()
                          throws NotInLotException,
                                 ServiceUnavailableException

Returns the top level number of the car's current parking lot

Returns:

The top level number of the car's current parking lot

Throws:

NotInLotException - Thrown if the car is not in a lot

ServiceUnavailableException - Thrown if the database cannot be contacted or if some other reason prevents the system from returning the current lot's highest level

getMinLevel

public PaddedInteger getMinLevel()
                          throws NotInLotException,
                                 ServiceUnavailableException

Returns the bottom level number of the car's current parking lot

Returns:

The bottom level number of the car's current parking lot

Throws:

NotInLotException - Thrown if the car is not in a lot

ServiceUnavailableException - Thrown if the database cannot be contacted or if some other reason prevents the system from returning the current lot's lowest level

getOtherLotAvailability

public PaddedIntegerSeq getOtherLotAvailability(int lot)
                                         throws LotNotFoundException,
                                                ServiceUnavailableException

Returns an array of other lots that have availability, sorted by lot distance such that closer lots are listed first

Parameters:

lot - The lot to get lot distances from

Returns:

An array of other lots that have availability

Throws:

LotNotFoundException - Thrown if the given lot number is not known to the system

ServiceUnavailableException - Thrown if the database cannot be contacted or if some other reason prevents the system from discovering the availability of other lots

moveDownLevel

public PaddedInteger moveDownLevel(int seq)
                            throws NotInLotException,
                                   AtBottomLevelException,
                                   ServiceUnavailableException

Moves the car from its present level to the level beneath it

Parameters:

seq - The latest sequence number of the client

Returns:

The level number that the client's car is now on

Throws:

NotInLotException - Thrown if the car is not in a lot

AtTopLevelException - Thrown if the car is already on the lowest level

ServiceUnavailableException - Thrown if the database cannot be contacted or if some other reason prevents the car from moving to the lower level

AtBottomLevelException

moveUpLevel

public PaddedInteger moveUpLevel(int seq)
                          throws NotInLotException,
                                 AtTopLevelException,
                                 ServiceUnavailableException

Moves the car from its present level to the level above it

Parameters:

seq - The latest sequence number of the client

Returns:

The level number that the client's car is now on

Throws:

NotInLotException - Thrown if the car is not in a lot

AtTopLevelException - Thrown if the car is already on the highest level

ServiceUnavailableException - Thrown if the database cannot be contacted or if some other reason prevents the car from moving to the next highest level

alreadyCompleted

protected boolean alreadyCompleted(int seq)
                            throws ServiceUnavailableException

Checks if the current client request has already been completed.

Parameters:

seq -

Returns:

Throws:

ServiceUnavailableException

updateClientData

protected void updateClientData(int seq,
                                int lot,
                                int level)
                         throws ServiceUnavailableException

Updates the client table, which is used for duplicate detection.

Parameters:

seq -

lot -

level -

Throws:

ServiceUnavailableException

printLotsStatus

protected void printLotsStatus(String message,
                               int seq)

Print the status of all the lots

Parameters:

message - The message to display with the status

seq - The client request sequence number

printLevelsStatus

protected void printLevelsStatus(String message,
                                 int seq)

Print the status of all the levels in the current lot

Parameters:

message - The message to display with the status

seq - The client request sequence number

padIntegerArray

protected PaddedIntegerSeq padIntegerArray(int[] value)

Pad the integer array in order to make it comply with the reply size of the analysis

Parameters:

value -

Returns:

padded value

padInteger

protected PaddedInteger padInteger(int value)

Pad the integer in order to make it comply with the reply size of the analysis

Parameters:

value -

Returns:

padded value

padVoid

protected PaddedVoid padVoid()

Pad the void in order to make it comply with the reply size of the analysis

Returns:

padded void