Tile Entity to make an Expanding Block?

[TheMajorN]

Heya, I'm trying to create a shield that you place on the ground and it quickly duplicates the source block and creates a 20x20 block wall (stopping at walls and other blocks and conforms to the shape.)  I have a tile entity ready and am in the tick method right now but I'm having trouble figuring out what to type as to accomplish such a task.  Any points in the right direction would be much appreciated!  In the meantime, I'll be doing some digging myself to try and figure it out, though I can't think of another expanding block in Minecraft that I can reference for it.

(Not an actual expanding block, just creating more of the same blocks for a certain range.)

Edited November 3, 2021 by TheMajorN
Clarification on how I meant "Expanding"

[Draco18s]

Blocks cannot be larger than 1x1x1. If you need it to fill more space, you need more blocks.

[TheMajorN]

Oh yeah sorry that's what I meant.  I would like more blocks of the same type to duplicate from the source block.

Thanks for pointing out the unclear point.  I'll fix that in the main post.

[Draco18s]

BlockPos#offset(direction, distance)

Level#setBlockState(pos, state)

[TheMajorN]

Thank you so much!  Though, what does # mean?  I've never seen that before in Java lol

[Draco18s]

It's javadoc notation, it means that the method is an instance method, not a static method.

You still use a . when calling it.

[TheMajorN]

Ah alright, thanks dude.