dm3270

Pure Java TN3270 terminal client library.

Loki Network Recording

Optional Loki TCP recording captures raw TN3270 network traffic for offline replay with the OpenLegacy Loki player.

API

Configure recording before calling connect():

TerminalClient client = new TerminalClient(2, new ScreenDimensions(24, 80));
client.setRecordingFile("/tmp/session.json");  // null or empty = disabled (default)
client.setRecordingSsl(false);                 // true when using an SSL SocketFactory
client.connect("mainframe.example.com", 623);
// ... use the session ...
client.disconnect();                           // writes the Loki JSON file

When recording is enabled, a WARN log is emitted: TN3270 network traffic is being recorded to: {file}.

Output format

The file is a Loki NetworkTrace JSON document with backendSolution set to MF_SCREENS_OL. It can be replayed with SingleSequentialTpcPlayerVertical or TcpPlayersControllerVerticle from loki-tcp-player.

Notes

• Recording starts at connect() and is flushed on disconnect().
• setRecordingFile() / setRecordingSsl() throw IllegalStateException if called after connect().
• Sniffy instrumentation is JVM-global; avoid concurrent recording sessions in the same JVM.
• Match SSL settings between recording and replay (setRecordingSsl must reflect the actual socket factory).

Build

./gradlew build

Requires OpenLegacy Artifactory credentials (ARTIFACTORY_OL_OPS_USER, ARTIFACTORY_OL_OPS_PASSWORD) for the loki-tcp-recorder dependency.