The javaspace component is a
transport for working with any JavaSpace compliant implementation
and this component has been tested with both the Blitz
implementation and the GigaSpace
implementation. This component can be used for sending
and receiving any object inheriting from the Jini
net.jini.core.entry.Entry
class. It is also
possible to pass the bean ID of a template that can be used for
reading/taking the entries from the space. This component can be
used for sending/receiving any serializable object acting as a sort
of generic transport. The JavaSpace component contains a special
optimization for dealing with the BeanExchange
.
It can be used to invoke a POJO remotely, using a JavaSpace as a
transport. This latter feature can provide a simple implementation
of the master/worker pattern, where a POJO provides the business
logic for the worker. Look at the test cases for examples of various
use cases for this component.
javaspace:jini://host[?options]
You can append query options to the URI in the following format,
?option=value&option=value&...
Name | Default Value | Description |
---|---|---|
spaceName
|
null
|
Specifies the JavaSpace name. |
verb
|
take
|
Specifies the verb for getting JavaSpace entries. The
values can be: take or
read . |
transactional
|
false
|
If true , sending and receiving entries
is performed within a transaction. |
transactionalTimeout
|
Long.MAX_VALUE
|
Specifies the transaction timeout. |
concurrentConsumers
|
1
|
Specifies the number of concurrent consumers getting entries from the JavaSpace. |
templateId
|
null
|
If present, this option specifies the Spring bean ID of the template to use for reading/taking entries. |
//Sending route from("direct:input").to("javaspace:jini://localhost?spaceName=mySpace"); //Receiving Route from("javaspace:jini://localhost?spaceName=mySpace&templateId=template&verb=take&concurrentConsumers=1")
In this case the payload can be any object that inherits from the
Jini Entry
type.
Using the preceding routes, it is also possible to send and
receive any serializable object. The JavaSpace component detects
that the payload is not a Jini Entry
and then it
automatically wraps the payload with a Camel Jini
Entry
. In this way, a JavaSpace can be used
as a generic transport mechanism.
The JavaSpace component has been tailored to work in combination with the Camel bean component. It is therefore possible to call a remote POJO using JavaSpace as the transport:
from("direct:input").to("javaspace:jini://localhost?spaceName=mySpace"); //Client side from("javaspace:jini://localhost?concurrentConsumers=10&spaceName=mySpace").to("pojo:pojo"); //Server side
In the code there are two test cases showing how to use a POJO to realize the master/worker pattern. The idea is to use the POJO to provide the business logic and rely on Apache Camel for sending/receiving requests/replies with the proper correlation.