Tuscany Calculator RMI Service Sample

Tuscany Calculator-RMI Service - A Simple SCA Assembly that hosts calculator functions as RMI Services

Overview

This sample is an assembly of Calculator functions implemented in Java and exposed as RMI Services. The primary objective of developing this sample is to support the Calculator-Combo sample.

To test this sample you might have to either run the Calculator-Combo sample after running this sample or you might write your won SCA Application that references the services of this sample

Location

The source for this sample is located in the paths - samples\standalone\calculatorRMIService of the source distribution.

If there is binary distribution available for these samples, then you may find these samples packaged as sample-calculator-rmiService.jar.

Building & Running the CalculatorRMIService Sample Source

If you are working with a source distribution, then you must first build the source of this sample.
- Ensure that you have Java 5 installed on your system.
- Next, you must have Maven 2.0.4 installed on your system. Look up http://maven.apache.org/download.html for downloading and installing Maven.

Building the CalculatorRMIService Sample

Having installed Maven, open a command line console and switch over to the directory on your local system, where you have extracted the source.
- Now switch futher into the subdirectory samples\standalone\calcualtorRMIService. Within this directory execute the following command

mvn

This will build the calculatorRMIService sample, package a JAR file for the composite and make it available in the sub-directory samples\standalone\calculatorRMIService/target

Setting up Tuscany Standalone Runtime

To run these samples you need the Tuscany Standalone Runtime. This is available as a distribution that can be conveniently unpacked and setup in the samples directory itself. For this, do the following: -

From the directory samples\standalone\calculatorRMIService execute the following command

>	mvn dependency:unpack

This will unpack the Tuscany Standalone Runtime Distribution to the target\distribution sub-directory within the present working directory - samples\standalone\calculatorRMIService

ii)

Since this sample would require the RMI Binding Extension of Tuscany you must copy the RMI Extension JAR from the contrib sub-directory into the extensions directory of the distribution. ie. execute the following from the samples\standalone\calculatorRMIService sub-directory: -

>	copy target\distribution\contrib\rmi-1.0-incubator-M2.jar target\distribution\extensions\rmi-1.0-incubator-M2.jar

Note : If you are working with SNAPSHOTs versions of Tuscany Extensions then the file rmi-1.0-incubator-M2.jar in the above command must be substituted with rmi-1.0-incubator-M2-SNAPSHOT.jar

Running the CalculatorRMIService Sample

Now that the sample source has been built and the Tuscany Standalone Runtime setup, you may run the CalculatorRMIService sample as follows: -

Switch to the samples\standalone\calculatorRMIService\target\distribution sub-directory and execute the following command:

>	java -jar bin\launcher.jar ..\sample-calculator-rmiService.jar

ii)

You will initially observe messages that relate to resolution of dependencies required to run this sample and finlly see the following message on your console
**********************************************
Calculator Rmi Service Started and Running...
***********************************************
Hit ENTER to exit

iii)

This message indicates that the CalculatorRMIServer has been successfully started and is running.

iv)

Whenever a client invokes this RMI Service, the console displays a message about the service method invoked.

Pressing the 'Enter' key will stop the RMI Server and the Tuscany Standalone Runtime, ending this sample with the following message
***********************************************************
Calculator RMI Service Stopped!
***********************************************************

Trying the CalculatorRMIService Sample

With the CalculatorRMIService started up and running you may try it out by writing your own RMI Client that can invoke the CalculatorRMIService. The details of the hostname, port and server name which your client should look up is as follows: -

host =	"localhost"
port =	"9999"
server name =	"rmiCalculator"

Note: You are free to modify any of the above (host, port, server name) by making corresponding modifications to the default.scdl file of the CalculatorRMIService sample and then running this sample.

Note : You may also try the CalculatorRMIService Sample by running the Calculator-Combo sample after running this sample. For details on setting up and running the Calculator-Combo sample look at the readme.html under that sample.

Code Overview

The source files are physically organized as shown below:

Calculator RMI Service
+---main
    +---java
    |   +---calculator
                <Interfaces and Implementations for Calculator Functions>

            +---server
                   CalculatorRMIServer.java
    +---resources
        +---META-INF
             +---sca
                   default.scdl

Calculator RMI Service Sample (Standalone Deployment)

default.scdl	Defines an assembly of calculator funtions implemented in Java and exposed as an RMI Service.
AddService.java AddServiceImpl.java DivideService.java DivideServiceImpl.java MathService.java MathServiceImpl.java MultiplyService.java MultiplyServiceImpl.java SubtractService.java SubtractServiceImpl.java	Java Interfaces and Java Implementations for various calculator functions..
CalculatorService.java CalculatorServiceImpl.java	Defines the coarse grained Calculator Interface and Implementation. This calculator implementation delegates function requests to other granular implemenations listed above.
CalculatorRMIServer	The main method of the RMI Server sample that keeps the runtime up and exits the appplication after the user presses 'Enter' key.