Fix fluid encoder JEI support not working #13

solidDoWant · 2026-01-20T07:53:15Z

JEI's "Move Items" button failed to transfer fluids to the native AE2 Pattern Terminal when EnderCore/EnderIO was present. Fluids were completely omitted from the pattern, while items worked correctly. The Extended Pattern Terminal was unaffected.

Root Cause

JEI's RecipeRegistry creates an immutable snapshot of recipe transfer handlers during construction. The original approach attempted to replace AE2's handler via reflection by modifying RecipeTransferRegistry, but this had two fatal flaws:

Non-deterministic plugin load order: JEI loads @JEIPlugin classes in an undefined order (from ASMDataTable.getAll() which returns an unordered Set). Sometimes our plugin loaded before AE2's, sometimes after.
Immutable handler cache: Even when the source registry was successfully modified via reflection, RecipeRegistry already held a frozen ImmutableTable snapshot taken during startup. Runtime modifications were never seen by the actual handler lookup code.

Solution

Implemented a Mixin (RecipeRegistryMixin) that intercepts RecipeRegistry.getRecipeTransferHandler() at runtime:

Detects when the lookup is for ContainerPatternTerm
Replaces AE2's fluid-unaware handler with our custom handler that converts fluids to fluid encoder items
Works regardless of plugin load order since it intercepts the actual runtime lookup

Changes

Added RecipeRegistryMixin.java - Mixin that intercepts handler lookups
Simplified JeiPlugin.java - Removed complex reflection code, now only registers Extended Pattern Terminal handler
Fixed RecipeTransferHandler.java - Force processing mode for fluids to avoid slot conflicts
Updated mixins.gregtechenergistics.json - Registered the new mixin

Testing

Verified with EnderCore/EnderIO enabled across multiple restarts - fluids now consistently appear as fluid encoder items when using JEI's "Move Items" button on the native AE2 Pattern Terminal.

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

Copilot

Pull request overview

Fixes JEI “Move Items” failing to transfer fluids into AE2’s native Pattern Terminal when EnderCore/EnderIO affects plugin load order, by replacing the runtime recipe transfer handler lookup instead of trying to mutate JEI’s startup snapshot.

Changes:

Added a JEI RecipeRegistry Mixin to override the handler returned for ContainerPatternTerm.
Simplified the JEI plugin registration to only register the Extended Pattern Terminal handler via public API.
Adjusted recipe transfer logic to avoid slot conflicts by forcing “processing mode” for fluids and adding null-guards.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
`src/main/resources/mixins.gregtechenergistics.json`	Registers the new JEI mixin so runtime handler interception is applied.
`src/main/java/com/soliddowant/gregtechenergistics/mixins/jei/RecipeRegistryMixin.java`	Intercepts `RecipeRegistry.getRecipeTransferHandler` and swaps AE2’s handler for the mod’s handler for `ContainerPatternTerm`.
`src/main/java/com/soliddowant/gregtechenergistics/integration/jei/RecipeTransferHandler.java`	Changes transfer behavior for fluids and server-side merging/preserve-slot logic.
`src/main/java/com/soliddowant/gregtechenergistics/integration/jei/JeiPlugin.java`	Removes reflection-based registry mutation; registers only the extended terminal handler.

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src/main/java/com/soliddowant/gregtechenergistics/integration/jei/RecipeTransferHandler.java

src/main/java/com/soliddowant/gregtechenergistics/integration/jei/JeiPlugin.java

Copilot · 2026-01-20T08:03:34Z

@solidDoWant I've opened a new pull request, #14, to work on those changes. Once the pull request is ready, I'll request review from you.

* Initial plan * Fix hasInputFluids and hasOutputFluids calculation Co-authored-by: solidDoWant <16456946+solidDoWant@users.noreply.github.com> --------- Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: solidDoWant <16456946+solidDoWant@users.noreply.github.com>

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

Copilot

Pull request overview

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

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src/main/resources/mixins.gregtechenergistics.json

src/main/java/com/soliddowant/gregtechenergistics/mixins/jei/RecipeRegistryMixin.java

src/main/java/com/soliddowant/gregtechenergistics/integration/jei/JeiPlugin.java

Copilot · 2026-01-20T08:24:14Z

@solidDoWant I've opened a new pull request, #15, to work on those changes. Once the pull request is ready, I'll request review from you.

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

…EI (#15) * Initial plan * Add IMixinConfigPlugin to gate JEI mixin behind mod presence check Co-authored-by: solidDoWant <16456946+solidDoWant@users.noreply.github.com> * Use startsWith for more precise JEI mixin package detection Co-authored-by: solidDoWant <16456946+solidDoWant@users.noreply.github.com> * Make JEI package detection more robust using mixinPackage parameter Co-authored-by: solidDoWant <16456946+solidDoWant@users.noreply.github.com> * Extract JEI constants and fix formatting Co-authored-by: solidDoWant <16456946+solidDoWant@users.noreply.github.com> * Add documentation for JEI package convention Co-authored-by: solidDoWant <16456946+solidDoWant@users.noreply.github.com> --------- Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: solidDoWant <16456946+solidDoWant@users.noreply.github.com>

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

Copilot

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

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src/main/java/com/soliddowant/gregtechenergistics/integration/jei/RecipeTransferHandler.java

src/main/java/com/soliddowant/gregtechenergistics/mixins/jei/RecipeRegistryMixin.java

Copilot · 2026-01-20T08:47:25Z

@solidDoWant I've opened a new pull request, #16, to work on those changes. Once the pull request is ready, I'll request review from you.

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

solidDoWant added 2 commits January 20, 2026 07:37

try mixin approach

cbbde37

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

remove d ebug code

c63fdeb

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

solidDoWant requested a review from Copilot January 20, 2026 07:53

Copilot started reviewing on behalf of solidDoWant January 20, 2026 07:53 View session

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Copilot AI mentioned this pull request Jan 20, 2026

Fix hasInputFluids check to prevent shaped recipe compression #14

Merged

Copilot AI and others added 3 commits January 20, 2026 02:10

rm dead code

ab8bbcb

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

rm old import, warning

476d22f

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

solidDoWant requested a review from Copilot January 20, 2026 08:16

Copilot started reviewing on behalf of solidDoWant January 20, 2026 08:16 View session

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Copilot AI mentioned this pull request Jan 20, 2026

Gate JEI mixin behind mod presence check to prevent crashes without JEI #15

Merged

solidDoWant and others added 3 commits January 20, 2026 08:26

address PR comments

3dc75f4

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

fix import

b548fc0

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

solidDoWant requested a review from Copilot January 20, 2026 08:39

Copilot started reviewing on behalf of solidDoWant January 20, 2026 08:39 View session

Copilot AI reviewed Jan 20, 2026

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Copilot AI mentioned this pull request Jan 20, 2026

Verify fluid handling in crafting recipes #16

Closed

Statically init GT_ENERGISTICS_HANDLER

ff00260

Signed-off-by: solidDoWant <fred.heinecke@yahoo.com>

solidDoWant merged commit 491b1b7 into main Jan 20, 2026

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Fix fluid encoder JEI support not working #13

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solidDoWant commented Jan 20, 2026

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