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Tickwise
ErrorPluginsSIG-PL-010

Recurring exceptions in a plugin's scheduler tasks (Task #N generated an exception)

Platforms
Paper · Purpur · single server
Verified
Verified
Confidence
Confidence 85%

What it looks like in the log

Any one of these lines is enough. The agent matches them locally, on your server.

logs/latest.log
  • [WARN] generated an exception

Symptoms

  • A plugin's periodic feature (autosave, timers, scoreboard updates) does not work or works only partly
  • The log repeatedly shows: “Task #N for <plugin> vX generated an exception”

Cause

A task the plugin scheduled through the Bukkit/Paper scheduler throws an exception on every run. The cause is in the stack trace: a plugin bug, a wrong config, or a dependency on a disabled plugin/unavailable resource.

Possible causes

  • A plugin bug (NullPointerException and the like in its own classes)
  • The task accesses a disabled plugin or an unavailable resource (database, web API)
  • The plugin version is incompatible with the server (NoSuchMethodError etc. in the trace)

How to fixLow risk

  1. Use the evidence to identify the plugin (the name after for/Plugin) and the exception in the first line of the trace and in Caused by:.
  2. Check whether the plugin the task accesses is disabled (“plugin is disabled” messages, enable errors earlier in the log) and whether external resources are available.
  3. Update the plugin; if the error persists, send the author the full trace along with the server/plugin versions.
  4. If the errors spam the log and get in the way, temporarily disable the offending feature in the plugin config.

Translated from the Russian original; log lines are quoted verbatim.

Sources