Hello, I am looking to change the behavior of water and lava blocks, basically I want to make so that the lava doesn't burn the player and that water burns the player.

I found that the line that handles lava burning is in the onEntityCollision method on the FlowingFluidBlock class:

 

public void onEntityCollision(BlockState state, World worldIn, BlockPos pos, Entity entityIn) {
      if (this.fluid.isIn(FluidTags.LAVA)) {
         entityIn.setInLava();
      }

   }

 

the method checks if the fluid is lava, so I tought that I could create a class that extends this one and modify only that method. But I can't seem to be able to re-define the lava and water blocks on the Blocks class. (I am using reflection to do that, since the fields are final).

 

Field lavafield = Blocks.class.getDeclaredField("LAVA"); // LAVA field from Blocks (THIS IS WHERE THE EXCEPTION OCCURS)
Field waterfield = Blocks.class.getDeclaredField("WATER"); // WATER field from Blocks
Field modifiersField = Field.class.getDeclaredField("modifiers"); // modifiers of a field
modifiersField.setAccessible(true); // make modifiers public
modifiersField.setInt(lavafield, lavafield.getModifiers() & ~Modifier.FINAL); // set LAVA public
modifiersField.setInt(waterfield, waterfield.getModifiers() & ~Modifier.FINAL); // set WATER public
lavafield.set(null, register("lava", new PatchedFlowingFluidBlock(Fluids.LAVA, Block.Properties.create(Material.LAVA).doesNotBlockMovement().tickRandomly().hardnessAndResistance(100.0F).lightValue(15).noDrops()))); // Redefine the block with the "patched" FlowingFluidBlock that checks for water to burn.
waterfield.set(null, register("water", new PatchedFlowingFluidBlock(Fluids.WATER, Block.Properties.create(Material.WATER).doesNotBlockMovement().hardnessAndResistance(100.0F).noDrops()))); // The same as the line before

 

This is my new onEntityCollision:

 

@Override
public void onEntityCollision(BlockState state, World worldIn, BlockPos pos, Entity entityIn) {
	if (this.getFluid().isIn(FluidTags.WATER)) {
		entityIn.setInLava();
    }
}

 

This approach doesn't work (It gives a NoSuchFieldException in the first line, idk why) and also I believe it is very hacky because is uses reflection, modifying final fields and using deprecated methods.

 

Is there a better/easier way to do this?

Edited June 25, 20205 yr by Taimander

@diesieben07 Oh thank you very much. I didn't know tags existed haha. I was overcomplicating everything, this is much easier.