org.jpos.space

Interface Space<K,V>

All Known Subinterfaces:

LocalSpace<K,V>

All Known Implementing Classes:

JDBMSpace, JESpace, SpaceInterceptor, SpaceLet, TSpace

public interface Space<K,V>

Space uses concepts described in the Linda Coordination Language that eases the implementation of other jPOS components (such as Channels, Muxes, etc.), but it is not by any means an attempt to provide a full implementation.

jPOS's Space is basically a Map where each entry is a LinkedList of values that can be used as a BlockingQueue

One can place entries on a queue by calling Space.out, take them by calling Space.in and read (without taking) by calling Space.rd

Since:

2.0

See Also:

TSpace, SpaceError, The Linda Coordination Language

Method Summary

Modifier and Type	Method and Description
boolean	existAny(K[] keys)
boolean	existAny(K[] keys, long timeout)
V	in(K key) Take an entry from the space, waiting forever until one exists.
V	in(K key, long timeout) Take an entry from the space, waiting a limited amount of time until one exists.
V	inp(K key) In probe takes an entry from the space if one exists, return null otherwise.
void	nrd(K key) Nrd (not read) waits forever until Key is not present in space Resolution for expiring entries is implementation dependant, but a minimum one-second is suggested.
V	nrd(K key, long timeout) Nrd (not read) waits up to timeout until Key is not present in space Resolution for expiring entries is implementation dependant, but a minimum one-second is suggested.
void	out(K key, V value) Write a new entry into the Space
void	out(K key, V value, long timeout) Write a new entry into the Space, with an timeout value
void	push(K key, V value) Write a new entry at the head of a queue.
void	push(K key, V value, long timeout) Write a new entry at the head of the queue with a timeout value
void	put(K key, V value) Write a single entry at the head of the queue discarding the other entries
void	put(K key, V value, long timeout) Write a single entry at the head of the queue discarding the other entries, with timeout.
V	rd(K key) Read an entry from the space, waiting forever until one exists.
V	rd(K key, long timeout) Read an entry from the space, waiting a limited amount of time until one exists.
V	rdp(K key) Read probe reads an entry from the space if one exists, return null otherwise.

Method Detail

out

void out(K key,
         V value)

Write a new entry into the Space

Parameters:

key - Entry's key

value - Object value

out

void out(K key,
         V value,
         long timeout)

Write a new entry into the Space, with an timeout value

Parameters:

key - Entry's key

value - Object value

timeout - timeout value in millis

in

V in(K key)

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

Parameters:

key - Entry's key

Returns:

value

rd

V rd(K key)

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

Parameters:

key - Entry's key

Returns:

value

in

V in(K key,
     long timeout)

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

Parameters:

key - Entry's key

timeout - millis to wait

Returns:

value or null

rd

V rd(K key,
     long timeout)

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

Parameters:

key - Entry's key

timeout - millis to wait

Returns:

value or null

inp

V inp(K key)

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

Parameters:

key - Entry's key

Returns:

value or null

rdp

V rdp(K key)

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

Parameters:

key - Entry's key

Returns:

value or null

nrd

void nrd(K key)

Nrd (not read) waits forever until Key is not present in space Resolution for expiring entries is implementation dependant, but a minimum one-second is suggested.

Parameters:

key - Entry's key

nrd

V nrd(K key,
      long timeout)

Nrd (not read) waits up to timeout until Key is not present in space Resolution for expiring entries is implementation dependant, but a minimum one-second is suggested.

Parameters:

key - Entry's key

timeout - millis to wait

Returns:

value or null

push

void push(K key,
          V value)

Write a new entry at the head of a queue.

Parameters:

key - Entry's key

value - Object value

push

void push(K key,
          V value,
          long timeout)

Write a new entry at the head of the queue with a timeout value

Parameters:

key - Entry's key

value - Object value

timeout - timeout value in millis

existAny

boolean existAny(K[] keys)

Parameters:

keys - array of keys to check

Returns:

true if one or more keys are available in the space

existAny

boolean existAny(K[] keys,
                 long timeout)

Parameters:

keys - array of keys to check

timeout - to wait for any of the entries to become available in millis

Returns:

true if one or more keys are available in the space

put

void put(K key,
         V value)

Write a single entry at the head of the queue discarding the other entries

Parameters:

key - Entry's key

value - Object value

put

void put(K key,
         V value,
         long timeout)

Write a single entry at the head of the queue discarding the other entries, with timeout.

Parameters:

key - Entry's key

value - Object value

timeout - timeout value in millis