gistfile1.java

public class PlayerDamageHistory {
	
	public static PlayerDamageHistory createDamageHistory(String attacker) {
		return new PlayerDamageHistory(attacker);
	}

	private final String attacker;
	private final long time;
	
	private PlayerDamageHistory(String attacker) {
		this.attacker = attacker;
		this.time = System.currentTimeMillis();
	}
	
	public String getAttacker() {
		return this.attacker;
	}
	
	public Long getTime() {
		return this.time;
	}
}

//When player is hit
lastHit.put(victim.getName(), PlayerDamageHistory.createDamageHistory(attacker.getName()));

//When player gets knocked off
PlayerDamageHistory history = lastHit.get(player.getName());
if (history != null) {
	if ((System.currentTimeMillis() - history.getTime()) < 15000){
		Player attacker = Bukkit.getPlayerExact(history.getAttacker());
		a.sendMessage(ChatColor.GREEN + player.getName() + ChatColor.GOLD + " was hit off the earth by " + ChatColor.GREEN +  attacker.getName() + ".");

		FishSlap run = ((FishSlap)a.getController());
		if (run != null) {
			run.addPoint(attacker, a);
		}
	} else {
		a.sendMessage(ChatColor.GREEN + player.getName() + ChatColor.GOLD + " fell off the earth.");
		lastHit.remove(player.getName());
	}
	
} else {
	a.sendMessage(ChatColor.GREEN + player.getName() + ChatColor.GOLD + " fell off the earth.");
}