com.aspc.commander

Class Connection

java.lang.Object

com.aspc.commander.Connection

All Implemented Interfaces:

ServerProcess, Executor

public class Connection
extends java.lang.Object
implements Executor, ServerProcess

Parse SQL like statements to implement in terms of DBObjects THREAD MODE: SINGLE THREADED a connection may only be accessed by one thread at a time.

Since:

3 December 2003

Author:

Nigel Leck

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Connection.Version

Field Summary

Fields

Modifier and Type	Field and Description
static java.util.concurrent.atomic.AtomicBoolean	DEFAULT_LOG_COMMANDS should by default log the commands.
static int	MAX_CURSOR_COUNT The maximum number of cursors allowed per connection.
static java.lang.String	THREAD_NAME_SIGNATURE The Signature part of the thread name.
static double	TOTAL_WEIGHT The total weight of all commands allowed to be running at one time.

Constructor Summary

Constructors

Constructor and Description
Connection(Connection rootConnection) Constructor for a new connection from another connection
Connection(ForkJoinDataSource fjDS) Constructor for a new connection from a MutableDataSource
Connection(Login login, java.util.TimeZone tz) Constructor for a new connection from a Login and timezone
Connection(Login login, java.util.TimeZone tz, boolean readonly) Constructor for a new connection from a Login and timezone
Connection(MutableDataSource mds) Constructor for a new connection from a MutableDataSource
Connection(Session session) Creates a new connection using the given session to get the login and timezone

Method Summary

Modifier and Type	Method and Description
void	close() dispose of this connection.
void	closeCursor(java.lang.String name) Close this cursor and release any resources held.
long	commit(java.lang.String reason) Commit the changes to the database.
static Connection	currentConnection() The current connection for this thread.
org.w3c.dom.Document	execute(java.lang.String isql) Connection was not intended to be multiple threaded but...
SoapResultSet	fetch(java.lang.String sql) run the passed commands and return the results as a JDBC record set.
java.lang.Object	getAttribute(java.lang.String code) Returns a previously set attribute
DataSource	getBestDataSource() Try to use Readonly datasource if no modifications have been made yet.
java.lang.String	getConnectionID() get the connection id
Command	getCurrentCommand() The current command that is being processed for this connection
java.lang.String	getCurrentSql() The currently running statement.
SQLCommand	getCursor(java.lang.String name) Gets the previously executed command from the unique name passed.
int	getCursorSize() get the cursor size
Login	getLogin() The login of this connection.
MutableDataSource	getMutableDataSource() Return the current mutable data source for this connection
java.lang.String	getProgressMsg() get the progress message
ReadOnlyDataSource	getReadOnlyDataSource() Get the current read only datasource for this connection
Session	getSession() get the session if any.
java.lang.String	getStateID() return the state ID
java.util.TimeZone	getTimeZone() The timezone of this executor
java.lang.String	getUserName() get the user name
Connection.Version	getVersion()
boolean	isCursorDisabled() Is the cursor feature turned off ?
boolean	isRowCountRequired() Do records sets require the ROW_COUNT option
boolean	isStateless() is the connection currently stateless.
Command	makeCommand(DBCommand bc) make a command for this DBCommand
java.lang.String	makeCursor(SQLCommand sql) Make a unique cursor id for this statement
java.lang.String	makeThreadName() Create and Returns the thread name
void	paused() This process has been paused.
void	resumed() This process has been started.
void	rollback() abort any changes not committed for this connection.
void	setAttribute(java.lang.String code, java.lang.Object data) Sets a attribute for this connection
void	setCursorDisable(boolean flag) turn on/off the cursor feature.
void	setCursorSize(int cursorSize) set the cursor size
void	setReadOnlyDataSource(ReadOnlyDataSource rds) set the readonly data source to use.
void	setRowCountRequired(boolean flag) Require the ROW_COUNT= for record sets.
void	setThreadName(java.lang.String title) Sets the connection's thread name
void	setVersion(Connection.Version version) Set the required version
void	terminated() This process has been terminated.
static int	zombieCount(java.lang.String code) Gets the zombie count for the given dbcommand code
static int	zombieWeight() Gets the zombie weight

Methods inherited from class java.lang.Object

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

Field Detail

MAX_CURSOR_COUNT

public static final int MAX_CURSOR_COUNT

The maximum number of cursors allowed per connection.

See Also:

Constant Field Values

DEFAULT_LOG_COMMANDS

public static final java.util.concurrent.atomic.AtomicBoolean DEFAULT_LOG_COMMANDS

should by default log the commands.

THREAD_NAME_SIGNATURE

public static final java.lang.String THREAD_NAME_SIGNATURE

The Signature part of the thread name. eg nigel:Commander: select * from person

See Also:

Constant Field Values

TOTAL_WEIGHT

public static final double TOTAL_WEIGHT

The total weight of all commands allowed to be running at one time.

See Also:

Constant Field Values

Constructor Detail

Connection

public Connection(@Nonnull
                  MutableDataSource mds)
           throws java.lang.Exception

Constructor for a new connection from a MutableDataSource

Parameters:

mds - The user's datasource

Throws:

java.lang.Exception - A serious problem

Connection

public Connection(@Nonnull
                  ForkJoinDataSource fjDS)
           throws java.lang.Exception

Constructor for a new connection from a MutableDataSource

Parameters:

fjDS - The fork join datasource

Throws:

java.lang.Exception - A serious problem

Connection

public Connection(@Nonnull
                  Login login,
                  @Nonnull
                  java.util.TimeZone tz)
           throws java.lang.Exception

Constructor for a new connection from a Login and timezone

Parameters:

login - The Login

tz - The timezone to use

Throws:

java.lang.Exception - A serious problem

Connection

public Connection(@Nonnull
                  Login login,
                  @Nonnull
                  java.util.TimeZone tz,
                  boolean readonly)
           throws java.lang.Exception

Constructor for a new connection from a Login and timezone

Parameters:

login - The Login

tz - The timezone to use

readonly -

Throws:

java.lang.Exception - A serious problem

Connection

public Connection(@Nonnull
                  Session session)
           throws java.lang.Exception

Creates a new connection using the given session to get the login and timezone

Parameters:

session - the session for this connection

Throws:

java.lang.Exception - a serious problem

Connection

public Connection(@Nonnull
                  Connection rootConnection)
           throws java.lang.Exception

Constructor for a new connection from another connection

Parameters:

rootConnection - the other connection

Throws:

java.lang.Exception - A serious problem

Method Detail

setVersion

public void setVersion(Connection.Version version)

Set the required version

Parameters:

version - the version

getVersion

@CheckReturnValue
 @Nonnull
public Connection.Version getVersion()

getSession

@CheckReturnValue
 @Nullable
public Session getSession()

get the session if any.

Returns:

the session

setRowCountRequired

public void setRowCountRequired(boolean flag)

Require the ROW_COUNT= for record sets.

Parameters:

flag - Does the client require a row count ?

isRowCountRequired

@CheckReturnValue
public boolean isRowCountRequired()

Do records sets require the ROW_COUNT option

Returns:

TRUE if the client requires a row count for every record set

getMutableDataSource

@CheckReturnValue
 @Nonnull
public MutableDataSource getMutableDataSource()

Return the current mutable data source for this connection

Returns:

The mutable data source

getCurrentSql

@CheckReturnValue
 @Nonnull
public java.lang.String getCurrentSql()

The currently running statement.

Returns:

The current statement

getLogin

@CheckReturnValue
 @Nonnull
public Login getLogin()

The login of this connection.

Returns:

The login

getUserName

@CheckReturnValue
 @Nonnull
public java.lang.String getUserName()

get the user name

Specified by:

getUserName in interface Executor

Returns:

the user name

getConnectionID

@CheckReturnValue
 @Nonnull
public java.lang.String getConnectionID()

get the connection id

Returns:

the connection id

isStateless

@CheckReturnValue
public boolean isStateless()

is the connection currently stateless.

Specified by:

isStateless in interface Executor

Returns:

TRUE if stateless

getStateID

@CheckReturnValue
 @Nullable
public java.lang.String getStateID()

return the state ID

Returns:

the State ID

getAttribute

@CheckReturnValue
 @Nullable
public java.lang.Object getAttribute(java.lang.String code)

Returns a previously set attribute

Parameters:

code - The code for the attribute to be fetched

Returns:

The value

setAttribute

public void setAttribute(java.lang.String code,
                         java.lang.Object data)

Sets a attribute for this connection

Parameters:

code - The code

data - The data

getBestDataSource

@CheckReturnValue
 @Nonnull
public DataSource getBestDataSource()

Try to use Readonly datasource if no modifications have been made yet.

Returns:

The read only datasource.

getReadOnlyDataSource

@CheckReturnValue
 @Nonnull
public ReadOnlyDataSource getReadOnlyDataSource()

Get the current read only datasource for this connection

Returns:

The data source

makeCursor

@CheckReturnValue
 @Nonnull
public java.lang.String makeCursor(@Nonnull
                                                               SQLCommand sql)
                                                        throws java.lang.Exception

Make a unique cursor id for this statement

Parameters:

sql - The command

Returns:

The cursor id

Throws:

java.lang.Exception - A serious problem

closeCursor

public void closeCursor(@Nonnull
                        java.lang.String name)
                 throws java.lang.Exception

Close this cursor and release any resources held.

Parameters:

name - The cursor name

Throws:

java.lang.Exception - A serious problem

currentConnection

@CheckReturnValue
 @Nullable
public static Connection currentConnection()

The current connection for this thread.

Returns:

The connection for this thread. NULL if no connection

getCursor

@CheckReturnValue
 @Nullable
public SQLCommand getCursor(@Nonnull
                                                         java.lang.String name)

Gets the previously executed command from the unique name passed.

Parameters:

name - The cursor name

Returns:

The previously executed command.

fetch

@CheckReturnValue
 @Nonnull
public SoapResultSet fetch(@Nonnull
                                                       java.lang.String sql)
                                                throws java.lang.Exception

run the passed commands and return the results as a JDBC record set.

Specified by:

fetch in interface Executor

Parameters:

sql - The commands to run

Returns:

The JDBC record set

Throws:

java.lang.Exception - A serious problem

execute

@CheckReturnValue
public org.w3c.dom.Document execute(@Nonnull
                                                      java.lang.String isql)
                                               throws java.lang.Exception

Connection was not intended to be multiple threaded but... I've sync'd this method to prevent known errors when called by multiple threads.

Specified by:

execute in interface Executor

Parameters:

isql - The commands to run

Returns:

The result XML document

Throws:

java.lang.Exception - A serious problem

zombieCount

@CheckReturnValue
public static int zombieCount(@Nonnull
                                                java.lang.String code)
                                         throws java.lang.Exception

Gets the zombie count for the given dbcommand code

Parameters:

code - the dbcommand code

Returns:

int the number of zombies

Throws:

java.lang.Exception - a serious problem

zombieWeight

@CheckReturnValue
public static int zombieWeight()
                                          throws java.lang.Exception

Gets the zombie weight

Returns:

int the weight

Throws:

java.lang.Exception - a serious problem

setThreadName

public void setThreadName(@Nonnull
                          java.lang.String title)

Sets the connection's thread name

Parameters:

title - The title of this connection

setReadOnlyDataSource

public void setReadOnlyDataSource(ReadOnlyDataSource rds)

set the readonly data source to use.

Parameters:

rds - the data source

rollback

public void rollback()

abort any changes not committed for this connection.

close

public void close()

dispose of this connection.

commit

public long commit(@Nonnull
                   java.lang.String reason)
            throws java.lang.Exception

Commit the changes to the database.

Parameters:

reason - The reason to be recorded in the transaction tables

Returns:

The transaction number

Throws:

java.lang.Exception - A problem occurred

getCurrentCommand

@CheckReturnValue
 @Nonnull
public Command getCurrentCommand()

The current command that is being processed for this connection

Returns:

The current command

makeCommand

@CheckReturnValue
 @Nonnull
public Command makeCommand(@Nonnull
                                                       DBCommand bc)
                                                throws java.lang.Exception

make a command for this DBCommand

Parameters:

bc - The database command

Returns:

The Command to be executed

Throws:

java.lang.Exception - A serious problem

setCursorDisable

public void setCursorDisable(boolean flag)

turn on/off the cursor feature. This is used for the JOB command.

Parameters:

flag - TRUE will disable cursors

isCursorDisabled

@CheckReturnValue
public boolean isCursorDisabled()

Is the cursor feature turned off ?

Returns:

TRUE if cursors have been disabled.

setCursorSize

public void setCursorSize(int cursorSize)

set the cursor size

Parameters:

cursorSize - the size

getCursorSize

@CheckReturnValue
public int getCursorSize()

get the cursor size

Returns:

the cursor size

paused

public void paused()

This process has been paused. MODE: Multi Threaded

Specified by:

paused in interface ServerProcess

resumed

public void resumed()

This process has been started. MODE: single threaded

Specified by:

resumed in interface ServerProcess

terminated

public void terminated()

This process has been terminated. MODE: Multi Threaded

Specified by:

terminated in interface ServerProcess

getProgressMsg

@CheckReturnValue
 @Nonnull
public java.lang.String getProgressMsg()

get the progress message

Returns:

the string message

makeThreadName

public java.lang.String makeThreadName()

Create and Returns the thread name

Specified by:

makeThreadName in interface ServerProcess

Returns:

thread name

See Also:

ServerProcess.makeThreadName()

getTimeZone

@CheckReturnValue
 @Nonnull
public java.util.TimeZone getTimeZone()

Description copied from interface: Executor

The timezone of this executor

Specified by:

getTimeZone in interface Executor

Returns:

the timezone.