Introduction

Software

Source Code

Grid Market Middtleware will be soon released under the GLPL open source licence.

Binaries

The file gmm.tar.gz contains the binaries required to execute the middleware.

Documentation

Samples

Echoes

This sample application presents a simple, yet very complete example of the main functionalities provided by the P2pAgent API, a fundamental part of the Grid Market Middleware.
The application shows two agents, EchoesServer and EchoesClient, which engage in a multiple communications of the type send/reply to implement a sort of "ping" command, as provided for TCPIP in most platforms. Along this process, the EchoesClient determines the average response time of the sever.

Throught this example we can show how the following functionalities are implemented:

Crete an agent and pass initialization parameters
Wait for an agent to complete and get results from it
Retrieve parameters passed to an agent and pass back results
Send and receive messages
Reply to an message received from other agent
Schedulle events to be executed in the future and handle them when the time expires
Report execution metrics that can be externaly analyzed
Keep a record of agent's the execution by means of log entries

Components

EchoesMainApp: is the main application that starts the client and server agents and pass to them the required parameters, as specified below.
EchoServer respond to requests received from cliets after waiting for a random delay that simulates the response time of the server. The delay is implemented by a schedulled event with a random delay time. When the event expires, the server replies to the client with the same message it received.
EchoClient send a series of requests to the EchoServer and records the response time of each request. The client for responses until either a minimun number of responses have been received or a timeout expiries. Upon finalization, calculates the average response time, reports it as a "ResponseTime" metrics and returns as a result argument to the caller application.

The EchoesSample.tar.gz file contains all the artifacts needed to setup an eclipse project to execute the Echoes sample application or develop other applications. In particular, it contains

src/ source files for the sample application
lib/ middleware's jar (p2pagent.jar) and required libraries
bin/ compiled classes
doc/ javadoc documentation for the sample application and the middleware's API
.project Eclipse project configuration
.classpath Eclipse project's classpath
profile.xml configuration for Jxta
HostingConfig.properties configuration for the GMM
EchoClient working directory for sample client application
EchoServer working directory for sample server application