The Functor Pattern Example

Prerequisites

To run this example the Oracle Coherence Incubator must be built and installed locally. Instructions on how to achieve this are located here: Building the Oracle Coherence Incubator.

Source Code

The source code for this example is located in the coherence-functorpattern-examples module of the Oracle Coherence Incubator.

Overview

The Functor Pattern example demonstrates how to use the Functor Pattern to set, increment and get the value of an attribute on a Context asynchronously.

It illustrates the main elements of the Functor Pattern, a Context, the FunctorSubmitter and a Functor.

There are four classes in the example:

1. FunctorPatternExample - The main application class.

2. Counter - An mutable implementation of the Context interface that represents a running counter.

3. NextValueFunctor - A Functor that wil increment a Counter.

4. LoggingCommand - A Command that will log the current state of a Context, in this case the Counter.

The FunctorPatternExample creates a new Counter which is then registered with the ContextsManager. The example then submits a LoggingCommand indicating that the application has commenced. In a tight loop, the Counter is incremented 50 times using the NextValueFunctor.

There are two approaches to running the example. First is using a simple entirely encapuslated approach. The second is using a client-server mode in which an Coherence Extend-based Client runs the actual FunctorPatternExample, backed by a Coherence Proxy-enabled Server the hosts the GenericContext.

The following instructions assume that $COHERENCE_INCUBATOR is the directory in which the Oracle Coherence Incubator source code has been downloaded, unpacked and built according to the prerequisites outlined above.

Running the Simple Example

Execute the following shell commands to run the Simple Example.

In a new Terminal / Shell Console for the "Example"

1. Change to the Functor Pattern Examples directory.

   cd $COHERENCE_INCUBATOR/coherence-functorpattern-examples/target

2. Run the Simple Example

   java -jar coherence-functorpattern-examples-11.0.0.jar simple.properties

Running in Client-Server Mode

Execute the following shell commands to run the example in Client-Server Mode.

In a new Terminal / Shell Console for the "Server"

1. Change to the Functor Pattern Examples directory.

   cd $COHERENCE_INCUBATOR/coherence-functorpattern-examples/target

2. Start the Coherence Server (and Proxy) Process/

   java -jar coherence-functorpattern-examples-11.0.0.jar server.properties

In a new Terminal / Shell Console for the "Client"

1. Change to the Functor Pattern Examples directory.

   cd $COHERENCE_INCUBATOR/coherence-functorpattern-examples/target

2. Start the Coherence Extend-based Client Application (example)

   java -jar coherence-functorpattern-examples-11.0.0.jar client.properties

You will notice the "Server" console that the logging commands are executing in the server, where are the "Client" console displays no such logging. This is because the Functors are executed at the Context, that of which is hosted by the "Server".

After this you may kill the "Server" application and close the consoles.