package com.JohnnyMccrum.JohnnyBaseMod.Structure;

    import com.JohnnyMccrum.JohnnyBaseMod.init.ModBlocks;
    import java.util.Random;
    import net.minecraft.block.Block;
    import net.minecraft.block.material.Material;
    import net.minecraft.init.Blocks;
    import net.minecraft.world.World;
    import net.minecraft.world.gen.feature.WorldGenerator;

public class StructureJohnnyFaceCave extends WorldGenerator
{
protected Block[] GetValidSpawnBlocks()
        {
return new Block[]
                    {
Blocks.grass,
Blocks.dirt,
Blocks.stone,
};
}

public boolean LocationIsValidSpawn(World world, int x, int y, int z)
        {
int distanceToAir = 0;
Block checkBlock = world.getBlock(x, y, z);

            while (checkBlock != Blocks.air)
            {
distanceToAir++;
checkBlock = world.getBlock(x, y + distanceToAir, z);
}

if (distanceToAir > 1)
            {
return false;
}

y += distanceToAir - 1;

Block block = world.getBlock(x, y, z);
Block blockAbove = world.getBlock(x, y + 1, z);
Block blockBelow = world.getBlock(x, y - 1, z);

            for (Block i : GetValidSpawnBlocks())
            {
if (blockAbove != Blocks.air)
                {
return false;
}
if (block == i)
                {
return true;
}
else if (block == Blocks.snow_layer && blockBelow == i) {
return true;
}
else if (block.getMaterial() == Material.plants && blockBelow == i)
            {
return true;
}
            }
return false;
}

public boolean generate(World world, Random rand, int x, int y, int z)
        {
if (!LocationIsValidSpawn(world, x, y, z) || !LocationIsValidSpawn(world, x + 12, y, z) || !LocationIsValidSpawn(world, x + 12, y, z + 20) || !LocationIsValidSpawn(world, x, y, z + 20)) {
return false;
}

world.setBlock(x + 0, y + 0, z + 0, Blocks.stone, 0, 3);
world.setBlock(x + 1, y + 0, z + 0, Blocks.dirt, 0, 3);
<snip>