MC - Menu Maker API

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Pattern;

import org.bukkit.Bukkit;
import org.bukkit.Material;
import org.bukkit.entity.Player;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.inventory.InventoryAction;
import org.bukkit.event.inventory.InventoryClickEvent;
import org.bukkit.inventory.Inventory;
import org.bukkit.inventory.ItemStack;
import org.bukkit.inventory.meta.ItemMeta;
import org.bukkit.plugin.java.JavaPlugin;

public class Menu {

        public interface ItemAction {
                public void run(Player player, Inventory inv, ItemStack item, int slot, InventoryAction action);
        }

        private String title = "";
        private int rows = 3;
        private HashMap<Integer, ItemStack> content = new HashMap<Integer, ItemStack>();
        private HashMap<Integer, ItemAction> commands = new HashMap<Integer, ItemAction>();
        private Inventory inventory;
        private JavaPlugin plugin;
        private ItemAction gaction;
        private boolean runempty = true;

        public Menu(JavaPlugin plugin, String title, int rows) {
                this(title, rows);
                setListener(plugin);
        }
        public Menu(JavaPlugin plugin, String title, int rows, ItemStack[] contents) {
                this(plugin, title, rows);
                setContents(contents);
        }
        public Menu(String title, int rows) throws IndexOutOfBoundsException {
                if (rows < 1 || rows > 6) throw new IndexOutOfBoundsException("Menu can only have between 1 and 6 rows.");
                this.title = title;
                this.rows = rows;
        }

        private void setListener(JavaPlugin pl) {
                pl.getServer().getPluginManager().registerEvents(new Listener() {
                        @EventHandler
                        public void onInvClick(InventoryClickEvent event) {
                                Player player = (Player) event.getWhoClicked();
                                Inventory inv = event.getInventory();
                                ItemStack item = event.getCurrentItem();
                                int slot = event.getRawSlot();
                                InventoryAction a = event.getAction();

                                if (item == null || item.getType() == Material.AIR) {
                                        if (!runempty) return;
                                }

                                if (inv.getName().equals(title)) {
                                        if (inv.equals(inventory)) {
                                                if (slot <= (rows*9)-1) {
                                                        event.setCancelled(true);
                                                        if (hasAction(slot)) commands.get(slot).run(player, inv, item, slot, a);
                                                        if (gaction != null) gaction.run(player, inv, item, slot, a);
                                                }
                                        }
                                }
                        }
                }, pl);
        }

        @Deprecated
        public boolean hasAction(int slot) {
                return commands.containsKey(slot);
        }

        @Deprecated
        public void setAction(int slot, ItemAction action) {
                commands.put(slot, action);
        }

        public void setGlobalAction(ItemAction action) {
                this.gaction = action;
        }

        public void removeGlobalAction() {
                this.gaction = null;
        }

        @Deprecated
        public void removeAction(int slot) {
                if (commands.containsKey(slot)) {
                        commands.remove(slot);
                }
        }

        public void runWhenEmpty(boolean state) {
                this.runempty = state;
        }

        public int nextOpenSlot() {
                int h = 0;
                for (Integer i : content.keySet()) {
                        if (i > h) h = i;
                }
                for (int i = 0; i <= h; i++) {
                        if (!content.containsKey(i)) return i;
                }
                return h+1;
        }

        public void setContents(ItemStack[] contents) throws ArrayIndexOutOfBoundsException {
                if (contents.length > rows*9) throw new ArrayIndexOutOfBoundsException("setContents() : Contents are larger than inventory.");
                content.clear();
                for (int i = 0; i < contents.length; i++) {
                        if (contents[i] != null && contents[i].getType() != Material.AIR) content.put(i, contents[i]);
                }
        }

        public void addItem(ItemStack item) {
                if (nextOpenSlot() > (rows*9)-1) {
                        plugin.getLogger().info("addItem() : Inventory is full.");
                        return;
                }
                setItem(nextOpenSlot(), item);
        }

        public void setItem(int slot, ItemStack item) throws IndexOutOfBoundsException {
                if (slot < 0 || slot > (rows*9)-1) throw new IndexOutOfBoundsException("setItem() : Slot is outside inventory.");
                if (item == null || item.getType() == Material.AIR) {
                        removeItem(slot);
                        return;
                }
                content.put(slot, item);
        }

        public void fill(ItemStack item) {
                for (int i = 0; i < rows*9; i++) content.put(i, item);
        }

        public void fillRange(int s, int e, ItemStack item) throws IndexOutOfBoundsException {
                if (e <= s) throw new IndexOutOfBoundsException("fillRange() : Ending index must be less than starting index.");
                if (s < 0 || s > (rows*9)-1) throw new IndexOutOfBoundsException("fillRange() : Starting index is outside inventory.");
                if (e < 0 || e > (rows*9)-1) throw new IndexOutOfBoundsException("fillRange() : Ending index is outside inventory.");
                for (int i = s; i <= e; i++) content.put(i, item);
        }

        public void removeItem(int slot) {
                if (content.containsKey(slot)) content.remove(slot);
        }

        public ItemStack getItem(int slot) {
                if (content.containsKey(slot)) return content.get(slot);
                return null;
        }

        public void setTitle(String title) {
                this.title = title;
        }

        public String getTitle() {
                return this.title;
        }

        public int rows() {
                return this.rows;
        }

        public void build() {
                this.inventory = Bukkit.createInventory(null, rows*9, this.title);
                inventory.clear();
                for (Map.Entry<Integer, ItemStack> entry : content.entrySet()) inventory.setItem(entry.getKey(), entry.getValue());
        }

        public Inventory getMenu() {
                build();
                return inventory;
        }

        public void showMenu(Player player) {
                player.openInventory(getMenu());
        }

        public ItemStack[] getContents() {
                return getMenu().getContents();
        }

        public ItemStack createItem(Material material, int amount, String name, String lore, short durability) throws IndexOutOfBoundsException {
                if (amount < 1 || amount > 64) {
                        throw new IndexOutOfBoundsException("Amount should be between 1 and 64.");
                }
                ItemStack item = new ItemStack(material, amount);
                ItemMeta meta = item.getItemMeta();

                if (name != null && name != "") {
                        meta.setDisplayName(name);
                }
                if (lore != null && lore != "") {
                        String[] lines = lore.split(Pattern.quote("^$"));
                        List<String> newlore = new ArrayList<String>();
                        for (String s : lines) {
                                newlore.add(s);
                        }
                        meta.setLore(newlore);
                }
                item.setDurability(durability);
                item.setItemMeta(meta);

                return item;
        }
        public ItemStack createItem(Material material, int amount, String name, String lore, short durability, byte data) throws IndexOutOfBoundsException {
                if (amount < 1 || amount > 64) {
                        throw new IndexOutOfBoundsException("Amount should be between 1 and 64.");
                }
                ItemStack item = new ItemStack(material, amount, data);
                ItemMeta meta = item.getItemMeta();

                if (name != null && name != "") {
                        meta.setDisplayName(name);
                }
                if (lore != null && lore != "") {
                        String[] lines = lore.split(Pattern.quote("^$"));
                        List<String> newlore = new ArrayList<String>();
                        for (String s : lines) {
                                newlore.add(s);
                        }
                        meta.setLore(newlore);
                }
                item.setDurability(durability);
                item.setItemMeta(meta);

                return item;
        }

}