Federate Protocol Client

Client library for HLA 4 Federate Protocol

TODO

Build jar using GitHub Actions
Publish jar to Maven Central
Add JUnit test

Building

The Federate Protocol Client and its dependencies can be build using the ant-target dist.all present in build.xml.

Regenerating build-targets

Regenerating the build-targets has to be done when module dependencies has changed. For the java build, the plugin 'Ant Build Generation' in IntelliJ should be used, with the settings 'Generate single-file ant build' selected, and 'Enable UI forms compilations' disabled.

Components

Session component

Session states

The possible states a client session can be in are:

NEW, this is an initial state a session is in before the start() method has been called.
RUNNING and DROPPED, these are stable states that the session is expected to remain in for longer periods of time.
STARTING, RESUMING and TERMINATING, these are transitory states that a session would be in for shorter periods of time.
TERMINATED, this is a terminal state which a session will not transition away from. A session will never do any more work as soon as this state is reached.

See the JavaDoc or the Doxygen for the State enum for details on each state.

The graph below describes the possible state transitions of a client session. The dotted lines are considered "exceptional" transitions, which occur due to unexpected events like for example timeouts or network failures.

---
title: All possible state transitions
---
%% http://mermaid.js.org/syntax/flowchart.html
flowchart TD
      S((START))
      E((END))
      S ==> NEW ==> STARTING
      STARTING ==> RUNNING
      STARTING -.-> TERMINATED
      RUNNING ==> TERMINATING
      RUNNING -.-> DROPPED
      DROPPED ==> TERMINATING
      DROPPED ==> RESUMING
      RESUMING ==> RUNNING
      RESUMING -.-> DROPPED
      RESUMING -.-> TERMINATED
      TERMINATING ==> TERMINATED
      TERMINATING -.-> TERMINATED
      TERMINATED ==> E

Samples

AsyncChat

AsyncChat is a basic sample that uses asynchronous versions of updateAttributeValues() and sendInteraction().

AsyncChatAdvanced

AsyncChatAdvanced uses asynchronous versions of HLA services whenever possible, and makes use of many more methods of CompletableFuture than AsyncChat does. For a good primer on CompletableFuture, see this article: https://liakh-aliaksandr.medium.com/asynchronous-programming-in-java-with-completablefuture-47ab86458aab

antelius/FedProClient