SimpleTP - A simple plugin for bukkit that has the /tpa command.

plugin.yml

name: SimpleTP
version: b4
description: Adds simple teleport request functionality to a bukkit server.
author: Sushi
main: net.openprog.simpletp.SimpleTP

commands:
  tpa:
    description: Send a teleport request to a player on the server.
    aliases: [tpr, tprequest]
    permission: simpletp.tpa
    permission-message: You do not have permission to use this command!
  tpaccept:
    description: Accept a teleport request.
    aliases: accept
    permission: simpletp.tpaccept
    permission-message: You do not have permission to use this command!
  tpdeny:
    description: Deny a teleport request.
    aliases: deny
    permission: simpletp.tpdeny
    permission-message: You do not have permission to use this command!

permissions:
  simpletp.tpa:
    description: Allows you to use the /tpa command.
    default: true
  simpletp.tpaccept:
    description: Allows you to use the /tpaccept command.
    default: true
  simpletp.tpdeny:
    description: Allows you to use the /tpdeny command.
    default: true

SimpleTP.java

package net.openprog.simpletp;

import java.util.HashMap;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;

import org.bukkit.ChatColor;
import org.bukkit.command.Command;
import org.bukkit.command.CommandSender;
import org.bukkit.entity.Player;
import org.bukkit.plugin.java.JavaPlugin;

public class SimpleTP extends JavaPlugin {
	Logger log  = Logger.getLogger("Minecraft");
	Map<String, Long> tpaCooldown = new HashMap<String, Long>();
	Map<String, String> currentRequest = new HashMap<String, String>();
	
	public void onEnable() {
		loadConfig();
		log.log(Level.INFO, String.format("[%s] Successfully enabled version %s!", getDescription().getName(), getDescription().getVersion()));
	}
	
	public void onDisable() {
		log.log(Level.INFO, String.format("[%s] Successfully disabled version %s!", getDescription().getName(), getDescription().getVersion()));
	}
	
	public boolean onCommand(CommandSender sender, Command cmd, String commandLabel, String[] args) {
		Player p = null;
		if (sender instanceof Player) {
			p = (Player) sender;
		}
		
		if (cmd.getName().equalsIgnoreCase("tpa")) {
			if (!(p == null)) {
				if (p.hasPermission("simpletp.overridecooldown")) {
					
				} else {
					int cooldown = getConfig().getInt("tpa-cooldown");
					if (tpaCooldown.containsKey(p.getName())) {
						long diff = (System.currentTimeMillis() - tpaCooldown.get(sender.getName())) / 1000;
						if (diff < cooldown) {
							p.sendMessage(ChatColor.RED + "Error: You must wait a " + cooldown + " second cooldown in between teleport requests!");
							return false;
						}
					}
				}
				
				if (args.length > 0) {
					final Player target = getServer().getPlayer(args[0]);
					long keepAlive = getConfig().getLong("keep-alive") * 20;
					
					if (target == null) {
						sender.sendMessage(ChatColor.RED + "Error: You can only send a teleport request to online players!");
						return false;
					}
					
					if (target == p) {
						sender.sendMessage(ChatColor.RED + "Error: You can't teleport to yourself!");
						return false;
					}
					
					sendRequest(p, target);
					
					getServer().getScheduler().scheduleSyncDelayedTask(this, new Runnable() {
						public void run() {
							killRequest(target.getName());
						}
					}, keepAlive);
					
					tpaCooldown.put(p.getName(), System.currentTimeMillis());
				} else {
					p.sendMessage("Send a teleport request to a player.");
					p.sendMessage("/tpa <player>");
				}
			} else {
				sender.sendMessage(ChatColor.RED + "Error: The console can't teleport to people, silly!");
				return false;
			}
			return true;
		}
		
		if (cmd.getName().equalsIgnoreCase("tpaccept")) {
			if (!(p == null)) {
				if (currentRequest.containsKey(p.getName())) {
					
					Player heIsGoingOutOnADate = getServer().getPlayer(currentRequest.get(p.getName()));
					currentRequest.remove(p.getName());
					
					if (!(heIsGoingOutOnADate == null)) {
						heIsGoingOutOnADate.teleport(p);
						p.sendMessage(ChatColor.GRAY + "Teleporting...");
						heIsGoingOutOnADate.sendMessage(ChatColor.GRAY + "Teleporting...");
					} else {
						sender.sendMessage(ChatColor.RED + "Error: It appears that the person trying to teleport to you doesn't exist anymore. WHOA!");
						return false;
					}
				} else {
					sender.sendMessage(ChatColor.RED + "Error: It doesn't appear that there are any current tp requests. Maybe it timed out?");
					return false;
				}
			} else {
				sender.sendMessage(ChatColor.RED + "Error: The console can't accept teleport requests, silly!");
				return false;
			}
			return true;
		}

		if (cmd.getName().equalsIgnoreCase("tpdeny")) {
			if (!(p == null)) {
				if (currentRequest.containsKey(p.getName())) {
					Player poorRejectedGuy = getServer().getPlayer(currentRequest.get(p.getName()));
					currentRequest.remove(p.getName());
					
					if (!(poorRejectedGuy == null)) {
						poorRejectedGuy.sendMessage(ChatColor.RED + p.getName() + " rejected your teleport request! :(");
						p.sendMessage(ChatColor.GRAY + poorRejectedGuy.getName() + " was rejected!");
						return true;
					}
				} else {
					sender.sendMessage(ChatColor.RED + "Error: It doesn't appear that there are any current tp requests. Maybe it timed out?");
					return false;
				}
			} else {
				sender.sendMessage(ChatColor.RED + "Error: The console can't deny teleport requests, silly!");
				return false;
			}
			return true;
		}
		return false;
	}
	
	public boolean killRequest(String key) {
		if (currentRequest.containsKey(key)) {
			Player loser = getServer().getPlayer(currentRequest.get(key));
			if (!(loser == null)) {
				loser.sendMessage(ChatColor.RED + "Your teleport request timed out.");
			}
			
			currentRequest.remove(key);
			
			return true;
		} else {
			return false;
		}
	}
	
	public void sendRequest(Player sender, Player recipient) {
		sender.sendMessage("Sending a teleport request to " + recipient.getName() + ".");
		
		String sendtpaccept = "";
		String sendtpdeny = "";
		
		if (recipient.hasPermission("simpletp.tpaccept")) {
			sendtpaccept = " To accept the teleport request, type " +  ChatColor.RED + "/tpaccept" + ChatColor.RESET + ".";
		} else {
			sendtpaccept = "";
		}
		
		if (recipient.hasPermission("simpletp.tpdeny")) {
			sendtpdeny = " To deny the teleport request, type " + ChatColor.RED + "/tpdeny" + ChatColor.RESET + ".";
		} else {
			sendtpdeny = "";
		}
		
		recipient.sendMessage(ChatColor.RED + sender.getName() + ChatColor.RESET + " has sent a request to teleport to you." + sendtpaccept + sendtpdeny);
		currentRequest.put(recipient.getName(), sender.getName());
	}
	
	public void loadConfig() {
		getConfig().addDefault("tpa-cooldown", 5);
		getConfig().addDefault("keep-alive", 30);
		getConfig().options().copyDefaults(true);
		saveConfig();
	}
}