Right Click Help Please

package com.stepoffmysweg.cavewriting;

import org.bukkit.Bukkit;
import org.bukkit.ChatColor;
import org.bukkit.Material;
import org.bukkit.command.Command;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;
import org.bukkit.event.Listener;
import org.bukkit.event.block.Action;
import org.bukkit.event.player.PlayerInteractEvent;
import org.bukkit.inventory.ItemStack;
import org.bukkit.inventory.ShapedRecipe;
import org.bukkit.inventory.meta.ItemMeta;
import org.bukkit.plugin.java.JavaPlugin;

public class CaveWriting extends JavaPlugin implements Listener{

	public void onEnable(){
		addRecipes();
		Bukkit.getServer().getPluginManager().registerEvents(this, this);
	}

	public void onDisable(){

	}

	private void addRecipes() {
	 //Cave Writing Stick
	                ShapedRecipe g = new ShapedRecipe(writingstick());
	                g.shape(" * ", " E ", " E ");
	                g.setIngredient('*', Material.FLINT);
	                g.setIngredient('E', Material.STICK);
	                getServer().addRecipe(g);
	        }

	 private ItemStack writingstick() {
         ItemStack i = new ItemStack(Material.BLAZE_ROD, 1);
         ItemMeta m = i.getItemMeta();
         m.setDisplayName("Cave Writing Stick");
         i.setItemMeta(m);
         return i;
 }

	 public void playerInteractEvent(PlayerInteractEvent e) {
	    	Player player = e.getPlayer();
	    	if(e.getAction() == Action.RIGHT_CLICK_AIR || e.getAction() == Action.RIGHT_CLICK_BLOCK) {
	    		if(player.getItemInHand().getType() == Material.DIAMOND) {
	    			player.sendMessage(ChatColor.RED + "You just right clicked with a diamond!");
	    		}
	    	}
	    }

	@Override
	public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args) {
		if (cmd.getName().equalsIgnoreCase("stick")) {
			if(sender instanceof Player){
				Player player = (Player) sender;
				player.getInventory().addItem(writingstick());
			} else {
				sender.sendMessage(ChatColor.DARK_RED + "Only works with players!");
			}
		}
		return false;
	}
}