Creating Sign Permissions?

I'm having trouble with coding permissions for my command signs.

Code:java

@EventHandler
public void onSignChange(SignChangeEvent v) {
 
if (v.getLine(0).equalsIgnoreCase("[Heal]")) {
v.setLine(0, "§4[Heal]");
v.setLine(1, "§0Click Here To");
v.setLine(2, "Be Healed!");
}

I would like to add a permission to this so that not just anyone can create the signs :3
if any one could help that would be great ^_^

 

Code:java

@EventHandler
public void onSignChange(SignChangeEvent v) {
     if (v.getLine(0).equalsIgnoreCase("[Heal]")) {
          ////////////////////////////////////////////////////////////////
          if (!v.getPlayer().hasPermission("random.permission.goes.here")) {
               v.getPlayer().sendMessage("Noap");
               return;
          }
          ////////////////////////////////////////////////////////////////
          v.setLine(0, "§4[Heal]");
          v.setLine(1, "§0Click Here To");
          v.setLine(2, "Be Healed!");
     }
}

 

Thank you ^_^