org.jpos.space
Class JDBMSpace

java.lang.Object
  java.util.TimerTask
      org.jpos.space.JDBMSpace

All Implemented Interfaces:

java.lang.Runnable, Space

public class JDBMSpace
extends java.util.TimerTask
implements Space

JDBM based persistent space implementation

Since:

1.4.7

Version:

$Revision: 2594 $ $Date: 2008-01-22 08:41:31 -0800 (Tue, 22 Jan 2008) $

Author:

Alejandro Revilla, Kris Leite

Field Summary

static long

GCDELAY

Method Summary

void	close() close this space - use with care
void	commit() force commit
void	gc() garbage collector.
java.lang.String	getKeys()
static JDBMSpace	getSpace()
static JDBMSpace	getSpace(java.lang.String name) creates a named JDBMSpace (filename used for storage is the same as the given name)
static JDBMSpace	getSpace(java.lang.String name, java.lang.String filename) creates a named JDBMSpace
java.lang.Object	in(java.lang.Object key) Take an entry from the space, waiting forever until one exists.
java.lang.Object	in(java.lang.Object key, long timeout) Take an entry from the space, waiting forever until one exists.
java.lang.Object	inp(java.lang.Object key) In probe takes an entry from the space if one exists, return null otherwise.
void	out(java.lang.Object key, java.lang.Object value) Write a new entry into the Space
void	out(java.lang.Object key, java.lang.Object value, long timeout) Write a new entry into the Space The entry will timeout after the specified period
void	push(java.lang.Object key, java.lang.Object value) Write a new entry at the head of a queue.
void	push(java.lang.Object key, java.lang.Object value, long timeout) Write a new entry into the Space at the head of a queue The entry will timeout after the specified period
java.lang.Object	rd(java.lang.Object key) Read an entry from the space, waiting forever until one exists.
java.lang.Object	rd(java.lang.Object key, long timeout) Read an entry from the space, waiting a limited amount of time until one exists.
java.lang.Object	rdp(java.lang.Object key) Read probe reads an entry from the space if one exists, return null otherwise.
void	rollback() force rollback
void	run()
void	setAutoCommit(boolean b) Use with utmost care and at your own risk.
long	size(java.lang.Object key)

Methods inherited from class java.util.TimerTask

cancel, scheduledExecutionTime

Methods inherited from class java.lang.Object

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

Field Detail

GCDELAY

public static final long GCDELAY

See Also:

Constant Field Values

Method Detail

getSpace

public static final JDBMSpace getSpace()

Returns:

reference to default JDBMSpace

getSpace

public static final JDBMSpace getSpace(java.lang.String name)

creates a named JDBMSpace (filename used for storage is the same as the given name)

Parameters:

name - the Space name

Returns:

reference to named JDBMSpace

getSpace

public static final JDBMSpace getSpace(java.lang.String name,
                                       java.lang.String filename)

creates a named JDBMSpace

Parameters:

name - the Space name

filename - the storage file name

Returns:

reference to named JDBMSpace

setAutoCommit

public void setAutoCommit(boolean b)

Use with utmost care and at your own risk. If you are to perform several operations on the space you should synchronize on the space, i.e:

   synchronized (sp) {
     sp.setAutoCommit (false);
     sp.out (..., ...)
     sp.out (..., ...)
     ...
     ...
     sp.inp (...);
     sp.commit ();    // or sp.rollback ();
     sp.setAutoCommit (true);
   }
 

Parameters:

b - true or false

commit

public void commit()

force commit

See Also:

setAutoCommit(boolean)

rollback

public void rollback()

force rollback

See Also:

setAutoCommit(boolean)

close

public void close()

close this space - use with care

out

public void out(java.lang.Object key,
                java.lang.Object value)

Write a new entry into the Space

Specified by:

out in interface Space

Parameters:

key - Entry's key

value - Object value

out

public void out(java.lang.Object key,
                java.lang.Object value,
                long timeout)

Write a new entry into the Space The entry will timeout after the specified period

Specified by:

out in interface Space

Parameters:

key - Entry's key

value - Object value

timeout - entry timeout in millis

push

public void push(java.lang.Object key,
                 java.lang.Object value)

Description copied from interface: Space

Write a new entry at the head of a queue.

Specified by:

push in interface Space

Parameters:

key - Entry's key

value - Object value

push

public void push(java.lang.Object key,
                 java.lang.Object value,
                 long timeout)

Write a new entry into the Space at the head of a queue The entry will timeout after the specified period

Specified by:

push in interface Space

Parameters:

key - Entry's key

value - Object value

timeout - entry timeout in millis

rdp

public java.lang.Object rdp(java.lang.Object key)

Read probe reads an entry from the space if one exists, return null otherwise.

Specified by:

rdp in interface Space

Parameters:

key - Entry's key

Returns:

value or null

inp

public java.lang.Object inp(java.lang.Object key)

In probe takes an entry from the space if one exists, return null otherwise.

Specified by:

inp in interface Space

Parameters:

key - Entry's key

Returns:

value or null

in

public java.lang.Object in(java.lang.Object key)

Description copied from interface: Space

Take an entry from the space, waiting forever until one exists.

Specified by:

in in interface Space

Parameters:

key - Entry's key

Returns:

value

in

public java.lang.Object in(java.lang.Object key,
                           long timeout)

Take an entry from the space, waiting forever until one exists.

Specified by:

in in interface Space

Parameters:

key - Entry's key

timeout - millis to wait

Returns:

value

rd

public java.lang.Object rd(java.lang.Object key)

Read an entry from the space, waiting forever until one exists.

Specified by:

rd in interface Space

Parameters:

key - Entry's key

Returns:

value

rd

public java.lang.Object rd(java.lang.Object key,
                           long timeout)

Read an entry from the space, waiting a limited amount of time until one exists.

Specified by:

rd in interface Space

Parameters:

key - Entry's key

timeout - millis to wait

Returns:

value or null

size

public long size(java.lang.Object key)

Returns:

aproximately queue size

run

public void run()

Specified by:

run in interface java.lang.Runnable

Specified by:

run in class java.util.TimerTask

gc

public void gc()

garbage collector. removes expired entries

getKeys

public java.lang.String getKeys()