Fix NPE during confirmation callback when player flow state is missing (Paper 1.21+)#77
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BenCodez merged 1 commit intoBenCodez:mainfrom Nov 28, 2025
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…n no flow entry exists This patch resolves a NullPointerException triggered in PlayerActionListener.failed() when a confirmation callback fires after the associated player flow state has already been cleared or aborted. Instead of directly accessing a potentially null Map.Entry from the low map, the code now performs proper null checks and safely terminates the flow using fail-safe logic. This prevents scheduled tasks from crashing and avoids repeated console warnings such as: java.lang.NullPointerException: Cannot invoke 'Map.getValue()' because the return value of 'HashMap.get(Object)' is null This issue was triggered when fast player actions caused asynchronous confirmation callbacks to fire after the flow object was removed (e.g., cancelling, teleporting, rapid confirm/deny interactions). Patch tested on Paper 1.21.10.
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Summary
This PR fixes a NullPointerException that occurs inside PlayerActionListener$2.failed()
when a confirmation callback attempts to access a flow entry that no longer exists.
Paper 1.21.x tightened async behavior and timing windows, which exposed a race
condition in the confirmation system. If the player cancels, teleports, or otherwise
causes the flow to clear before the callback is executed, the
flow.get(uuid)callreturns null, causing an NPE: java.lang.NullPointerException: Cannot invoke "Map$Entry.getValue()"
What this PR changes
Why it's needed
This fixes active errors triggered by players on modern Paper servers.
The exception does not affect plot integrity but spams console and interrupts
confirmation logic.
This patch is backwards compatible with earlier Spigot/Paper versions.