[MC-6883] Other hoppers can push items into locked hoppers Created: 10/Jan/13  Updated: 25/Apr/21  Resolved: 21/Jan/13

Status: Resolved
Project: Minecraft: Java Edition
Component/s: None
Affects Version/s: Snapshot 13w02a, Snapshot 13w02b, Snapshot 13w03a
Fix Version/s: None

Type: Bug
Reporter: Timothy Bailey Assignee: Unassigned
Resolution: Works As Intended Votes: 4
Labels: container, hopper, redstone, redstone-repeater
Environment:

Windows 7 64bit
Unmodded


Attachments: PNG File 2013-01-10_19.48.38.png    
Issue Links:
Duplicate
is duplicated by MC-7221 Hopper Locking Not Affecting Other Ho... Resolved
is duplicated by MC-7444 Powering a hopper doesn't make it sto... Resolved
is duplicated by MC-7659 Hopper won't stop Resolved
is duplicated by MC-7677 Hopper cart issue Resolved
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is duplicated by MC-7910 Whopper bug Resolved
is duplicated by MC-8135 Hopper Transfers to Other Hoppers whe... Resolved
is duplicated by MC-8380 When powered, hoppers don't behave co... Resolved
is duplicated by MC-8533 Hoppers will not pick up or take item... Resolved
is duplicated by MC-8868 Hoppers continue to unload even when ... Resolved
is duplicated by MC-9909 Hoppers "ARE" losing items to hoppers... Resolved
is duplicated by MC-10886 Hopper Problem Resolved
is duplicated by MC-11140 Hopper bug Resolved
is duplicated by MC-11917 Hopper receiving items when it is on Resolved
is duplicated by MC-12495 Hopper with redstone does not stop ho... Resolved
is duplicated by MC-12658 Powered Hopper still recives items th... Resolved
is duplicated by MC-14215 Hoppers working when powered Resolved
is duplicated by MC-33168 Hopper does a terrible job at locking... Resolved
is duplicated by MC-42022 Hopper absorb item even if it is lock Resolved
is duplicated by MC-52771 Hopper Problem Resolved
is duplicated by MC-112126 Locked Hoppers don't behave as they a... Resolved
is duplicated by MC-117473 Hoppers ignore redstone signal Resolved
is duplicated by MC-141438 Hopper improper operation Resolved
is duplicated by MC-142130 Hopper lock doesn't work Resolved
is duplicated by MC-156232 Hopper Transfering Glitch /w Redstone... Resolved
is duplicated by MC-192605 Locked hoppers are no longer working Resolved
is duplicated by MC-224079 Locked Hopper collects items Resolved
CHK:
Confirmation Status: Confirmed
Game Mode: Creative

 Description   

When powering a Hopper that is above a solid block or a container the items are held in place correctly within the Hopper. If however the Hopper is placed above a second Hopper then the second hopper will overpower the redstone signal and suck the items out regardless. This may not be a bug and be functioning as intended however, as Hoppers with containers above them are designed to suck out items.

Screenshot: Powering the 2nd Hopper in the chain as shown is completely ineffective as the 3rd Hopper still takes items out.

EDIT: This has been somewhat fixed in 13w02b by the fact that a powered Hopper now does not take items from above, so powering 2 sequential Hoppers in the chain would create an effective lock. Powering the first or the last Hopper in the chain would also be effective, this bug only occurs in long chains of vertical Hoppers, when trying to create a lock mid way down the stack.



 Comments   
Comment by [Mod] Torabi [ 03/Feb/13 ]

A redstone signal does not "lock" the hopper. It merely stops it from operating, meaning that it no longer pulls items from the space or container above it, and no longer pushes items into the space or container pointed to by its output. Because hoppers are containers, hoppers can pull items from other hoppers, regardless of their operational state.

The primary purpose of hoppers, as far as I can tell, is to give us a way to automatically put items in containers and pull them out. The enables the automatic collection of mob drops and the transportation of items via minecarts. They weren't necessarily intended to make sorting machines, but people will figure out a way that works regardless.

And, to put it simply, it's easier to program the way it is.

Comment by Tanner Loper [ 02/Feb/13 ]

Dinnerbone, merely making hoppers conductive would fix this. After all, they can somehow allow redstone to float on top of the hole. You say there is nothing to fix. Well, this compromises the most simple of sorting machines and forces minecrafters to use pistons ans minecarts. I don't know what you intend the hopper be used for, but if it is locked, it should be completely locked, not only partially. hogwash.

Comment by [Mojang] Nathan Adams [ 21/Jan/13 ]

Intentional. Powering it merely stops it from sucking items from above or pushing items down, but another hopper/dropper can do what it likes still.

Comment by Timothy Bailey [ 12/Jan/13 ]

Yea that is correct Louis. The lower hopper is taking items out of the hopper above it, despite the upper one being locked, thus rendering the lock pointless.

Comment by MegaScience [ 12/Jan/13 ]

Could someone explain this a bit better? The problem is that the hoppers below still take out items despite the hopper above being locked? In that case, that shouldn't be possible. In real world concept, I'd imagine locking a hopper would act as closing up it's outputs and forcing it shut. Whether that is actually how it is thought is another thing, but this behavior definitely defies the lock.

Comment by Tails [ 12/Jan/13 ]

Confirmed in 13w02b.

Comment by -- -- [ 11/Jan/13 ]

Can confirm.
I hope this isn't a feature.

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