Fix GUI startup freeze, JSON crash, and WebSocket thread bugs#5
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JoOkuma wants to merge 4 commits into
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Fix GUI startup freeze, JSON crash, and WebSocket thread bugs#5JoOkuma wants to merge 4 commits into
JoOkuma wants to merge 4 commits into
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The GUI would freeze on first launch because the JavaFX Application Thread was blocked inside MainApp while CondaEnvironmentFinder waited for user input (lock.wait). Move the conda-path lookup to a daemon thread so the loading screen renders immediately and Swing dialogs can receive events. JavaConnector crashed with JsonSyntaxException when the Python server sent a plain-text error message instead of a JSON object (e.g. an unhandled traceback). Wrap the Gson parse in a try-catch and route non-JSON payloads to the error log. Additional hardening: - UltrackConnector.startServer: guard against a null/empty ultrackPath before launching the subprocess, showing a clear error dialog instead of a silent NullPointerException. - CondaEnvironmentFinder.updateCondaEnvironments: switch from Runtime.exec(String) to ProcessBuilder so conda paths containing spaces are handled correctly on Windows. - ultrack_server.js: guard against undefined fetch response data and add a .catch() so network errors during server polling are logged rather than silently swallowed. Fixes royerlab/ultrack#160, royerlab/ultrack#243, #4
…-1 race
- UltrackConnector.connectToWebsocket: latch.await() was called on the
calling thread; since connectToUltrackWebsocket is invoked from JS
(JavaFX Application Thread), this froze the UI during the WebSocket
handshake — same class of bug as the startup freeze. The await+send
is now done in a daemon background thread.
- JavaConnector.onMessageConsumer: jsonObject.get("err_log"),
"std_log", and "status" had no null checks. If the server sends JSON
that omits any of these keys, a NullPointerException crashed the
message handler silently. Replaced with jsonObject.has() guards.
- JavaConnector.startUltrackServer: when startServer() returned early
because ultrackPath was null, port stayed -1. The method still called
javascriptConnector.call("setPort", -1), causing the JS polling loop
to spin on 127.0.0.1:-1/config/available indefinitely. Added an
early-return guard on port == -1.
- MainApp.onUpdateCondaEnv: InterruptedException was wrapped in
RuntimeException and re-thrown, which crashed the background thread
silently instead of restoring the interrupt flag.
JoOkuma
changed the title
UltrackConnector.connectToWebsocket: if the server isn't listening when c.connect() fires, onOpen is never called so the CountDownLatch stays at 1 and the background connect thread blocks forever. Add a 30-second timeout and an isOpen guard so the thread always exits — either by sending the message, reporting a timeout error, or silently returning when onErrorConsumer has already surfaced the failure. ultrack_server.js: the viewButton fetch had no null guard on the response data and no .catch(), so a non-OK response or network error would silently drop the view request. Mirror the same pattern already applied to the server-polling loop.
MainApp.java - onLoadUltrackPath: keep a reference to the ChangeListener and remove it before adding a new one, so repeated calls (conda env change) don't accumulate stale listeners that re-wire javaConnector on every page load. - Replace 'assert url != null' with a proper null check + error dialog; assertions are disabled at runtime by default and would silently pass. JavaConnector.java - stopUltrackServer: guard against null ultrackConnector so calling stop before the server is ever started doesn't throw NPE. CondaEnvironmentFinder.java - getUltrackPath: convert tail-recursive implementation to an iterative while-loop; users who repeatedly pick an environment without ultrack installed would otherwise overflow the call stack. ultrack_server.js - Declare all implicit globals with let/const so they are properly scoped rather than silently leaking onto the window object: connection_successfull, available_configs, link, config, human_name, inputs, input, value, id, prev, json, images_json, image_options, available, experimentJson, xml. pom.xml / tests - Add JUnit 5 dependency (test scope). - UltrackConnectorTest: isPortOpen utility and null/empty-path startServer guards. - CondaEnvironmentFinderTest: getUltrackPath resolves executable in bin/ultrack and Scripts/ultrack.exe without opening a dialog.
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Problem
Three distinct bugs were causing the plugin to be unusable on first launch and during tracking:
GUI freeze on startup (#243, server connection issue #4): The JavaFX Application Thread was blocked inside
MainAppwhileCondaEnvironmentFinderwaited for user input vialock.wait(). Because the JAT was stalled, the loading screen never rendered, and dialogs couldn't receive events — the window appeared frozen.Crash when server sends a plain-text error (error running ultrack plugging inside fiji ultrack#160): Python's
raise_error()sends a raw traceback string over the WebSocket.JavaConnector.onMessageConsumerpassed this directly togson.fromJson(..., JsonObject.class), which threwJsonSyntaxExceptionand crashed the message handler.GUI freeze during WebSocket connect:
UltrackConnector.connectToWebsocketcalledlatch.await()on the calling thread. SinceconnectToUltrackWebsocketis invoked from JavaScript (JavaFX thread), this blocked the JAT during the WebSocket handshake — the same class of bug as Minor refactor #1.Changes
MainApp.javaCondaEnvironmentFinder.getUltrackPath()to a daemon background thread so the JAT is never blocked.onUpdateCondaEnv: restore interrupt flag withThread.currentThread().interrupt()instead of wrapping inRuntimeException.JavaConnector.javagson.fromJson()in a try-catch; route plain-text / malformed responses to the error log instead of crashing.jsonObject.has()guards before accessing"err_log","std_log", and"status"keys to prevent NPE on partial JSON.startUltrackServeragainstport == -1(returned whenultrackPathis null) so the JS polling loop doesn't spin on127.0.0.1:-1/config/availableforever.UltrackConnector.javalatch.await()+c.send()into a daemon background thread so the WebSocket handshake no longer blocks the JavaFX Application Thread.ultrackPathat the start ofstartServer()with a clear error dialog.CondaEnvironmentFinder.javaupdateCondaEnvironmentsfromRuntime.exec(String)toProcessBuilderso conda paths containing spaces are handled correctly on Windows.ultrack_server.jsundefinedfetch response data..catch()to the polling loop so network errors are logged rather than silently swallowed.Related issues
Fixes royerlab/ultrack#160, royerlab/ultrack#243, #4