WorldGenerator

import java.util.Random;

import net.minecraft.block.Block;
import net.minecraft.init.Blocks;
import net.minecraft.util.math.BlockPos;
import net.minecraft.world.World;
import net.minecraft.world.biome.Biome;
import net.minecraft.world.biome.BiomeCache;
import net.minecraft.world.chunk.IChunkGenerator;
import net.minecraft.world.chunk.IChunkProvider;
import net.minecraft.world.gen.feature.WorldGenerator;
import net.minecraftforge.fml.common.IWorldGenerator;

public class WorldGeneratorxlfoodmod implements IWorldGenerator{

    public void generate(Random random, int chunkX, int chunkZ, World world, IChunkGenerator chunkGenerator, IChunkProvider chunkProvider)
    {
        int blockX = chunkX * 16;
        int blockZ = chunkZ * 16;

        switch(world.provider.getDimension())
        {
        case -1: generateNether(world, random, blockX, blockZ);
        break;
        case 0: generateOverworld(world, random, blockX, blockZ);
        break;
        case 1: generateEnd(world, random, blockX, blockZ);
        break;
        }

    }

    private void generateNether(World world, Random rand, int blockX, int blockZ)
    {

    }

    private void generateOverworld(World world, Random rand, int blockX, int blockZ)
    {
        WorldGenerator genVanillaFlower = new WorldGenxlfoodmod();
        Biome biome = world.getBiomeForCoordsBody(new BlockPos(blockX, 64, blockZ));
        {
            int MIN = 0;
            int MAX = 8;
            int numBushes = MIN + rand.nextInt(MAX - MIN);
            for(int i = 0; i < numBushes; i++)
            {
                int randX = blockX + rand.nextInt(16);
                int randZ = blockZ + rand.nextInt(16);
                genVanillaFlower.generate(world, rand, new BlockPos(randX, 24, randZ));
            }
        }
    }

    private void generateEnd(World world, Random rand, int blockX, int blockZ)
    {

    }

    public static int getGroundFromAbove(World world, int x, int z)
    {
        int y = 255;
        boolean foundGround = false;
        while(!foundGround && y-- >= 0)
        {
            Block blockAt = world.getBlockState(new BlockPos(x,y,z)).getBlock();
            foundGround = blockAt == Blocks.DIRT || blockAt == Blocks.GRASS;
        }

        return y;
    }

}