Listener

package me.ben.GlassDrops;

import java.util.Random;

import org.bukkit.Material;
import org.bukkit.World;
import org.bukkit.block.Block;
import org.bukkit.entity.Player;
import org.bukkit.event.Listener;
import org.bukkit.event.block.BlockBreakEvent;
import org.bukkit.inventory.ItemStack;

public class GlassDropListener implements Listener {

    private GlassDrops plugin;

    public GlassDropListener(GlassDrops instance) {
        plugin = instance;
    }

    Random chance = new Random();

    String world1 = plugin.getConfig().getString("Worlds.world");
    String nether = plugin.getConfig().getString("Worlds.nether");
    String world3 = plugin.getConfig().getString("Worlds.world3");
    String world4 = plugin.getConfig().getString("Worlds.world4");
    String world5 = plugin.getConfig().getString("Worlds.world5");
    String message = plugin.getConfig().getString("Message.Message");
    String colour = plugin.getConfig().getString("Message.Colour");
    int damChance = plugin.getConfig().getInt("Glass-Damage.Damage-Chance");
    int damAmount = plugin.getConfig().getInt("Glass-Damage.Damage-Amount");
    int dropChance = plugin.getConfig().getInt("Glass-Drops.Drop-Chance");
    boolean glass = plugin.getConfig().getBoolean("Blocks-Dropped.Glass");
    boolean glassPanes = plugin.getConfig().getBoolean("Blocks-Dropped.Glass-Panes");

    public void onBlockBreak(BlockBreakEvent event) {

        Block block = event.getBlock();
        Player player = event.getPlayer();
        String playerName = event.getPlayer().getName();
        World world = event.getPlayer().getWorld();

        if (event.getBlock() == null)
            return;

        if ((world.getName().equals(world1)) || world.getName().equals(nether) || world.getName().equals(world3) || world.getName().equals(world4) || world.getName().equals(world5)) {
            if (block.getType() == Material.GLASS) {
                if (glass = true) {
                    for (int counter = 1; counter < 100; counter++) {
                        int damage = 1 + chance.nextInt(100);
                        if (damage <= damChance) {
                            player.damage(damAmount);
                        }
                        if (plugin.droptoggle.contains(playerName)) {
                            block.setType(Material.AIR);
                            block.getWorld().dropItemNaturally(block.getLocation(), new ItemStack(Material.GLASS, 1));
                        }
                    }
                }
            }
            else if (block.getType() == Material.THIN_GLASS) {
                if (glassPanes = true) {
                    for (int counter = 1; counter < 100; counter++) {
                        int damage = 1 + chance.nextInt(100);
                        if (damage <= damChance) {
                            player.damage(damAmount);
                        }
                        if (plugin.droptoggle.contains(playerName)) {
                            block.setType(Material.AIR);
                            block.getWorld().dropItemNaturally(block.getLocation(), new ItemStack(Material.THIN_GLASS, 1));
                        }
                    }
                }
            }
        }
    }
}