[Demonstration 1]

[Buggy Method]
@Override
public void messageReceived(BoffoEvent _event) {
    /**
     * Also using cascading if else statements to catch events
     * within a given range.
     * Using literal ints until the event system is nailed down.
     */
    if (_event.getMessage().getCode() == 0) {
        // check user login data
    } else if (_event.getMessage().getCode() == 1) {
        printReceipt();
    } else if (_event.getMessage().getCode() <= 10) {
        //
        this.changePanel(_event);
    } else if (_event.getMessage().getCode() <= 20) {
        //
        this.preformAction(_event);
    }
    // If the messageString does not fall within range, ignore it.
}

[Buggy Hunk]
this.preformAction(_event);

[Patch]
this.performAction(_event);

[Demonstration 2]

[Buggy Method]
public final boolean dispatch(CommandSender sender, String cmd, String... oargs) throws IncorrectArgumentsException, NoPermissionException {
    if (!commands.containsKey(cmd))
        return true;
    CommandMapping command = commands.get(cmd);
    ArrayList<Object> params = new ArrayList<>();
    Parameter[] methodArgs = command.getMethod().getParameters();
    ArrayDeque<Parameter> parameters = new ArrayDeque<>(Arrays.asList(methodArgs));
    ArrayDeque<String> args = new ArrayDeque<>(Arrays.asList(oargs));
    while (!parameters.isEmpty()) {
        Parameter current = parameters.pop();
        if (args.peek() == null && isOptional(current)) {
            params.add(null);
            continue;
        }
        if (args.peek() == null && !isOptional(current) && !isSender(current))
            throw new IncorrectArgumentsException(String.format("No argument provided for parameter %s!", current.getName()));
        if (subclassOf(CommandSender.class, current)) {
            if (isSender(current)) {
                params.add(sender);
            } else {
                String spl = args.pop();
                Player pl = Bukkit.getServer().getPlayer(spl);
                if (pl != null)
                    params.add(pl);
                else
                    throw new IncorrectArgumentsException(String.format("Couldn't find player %s! Are they online?", spl));
            }
        } else if (subclassOf(String.class, current)) {
            if (current.isAnnotationPresent(Text.class)) {
                StringBuilder builder = new StringBuilder();
                args.forEach(builder::append);
                params.add(builder.toString());
                // this is a bad move but yeah
                break;
            }
        } else if (subclassOf(int.class, current)) {
            int arg;
            try {
                arg = Integer.valueOf(args.pop());
            } catch (NumberFormatException e) {
                throw new IncorrectArgumentsException(String.format("Parameter %s requires an INTEGER.", current.getName()));
            }
            params.add(arg);
        } else if (subclassOf(boolean.class, current)) {
            String arg = args.pop();
            if (arg.equalsIgnoreCase("true"))
                params.add(true);
            else if (arg.equalsIgnoreCase("false"))
                params.add(false);
            else
                throw new IncorrectArgumentsException(String.format("Parameter %s requires a BOOLEAN.", current.getName()));
        } else if (subclassOf(OfflinePlayer.class, current)) {
            String spl = args.pop();
            OfflinePlayer opl = Bukkit.getServer().getOfflinePlayer(spl);
            if (opl != null)
                params.add(opl);
            else
                throw new IncorrectArgumentsException(String.format("Couldn't find offline player %s!", spl));
        }
    }
    // Check permission
    if (command.getPermission() != null && !sender.hasPermission(command.getPermission())) {
        throw new NoPermissionException();
    }
    // Invoke command
    try {
        command.invoke(params.toArray());
        return true;
    } catch (InaccessibleMethodException e) {
        sender.sendMessage(ChatColor.RED + "There was an error processing your command. Try again?");
        Logger.err("Could not invoke method for command " + cmd + "!");
        e.printStackTrace();
        return false;
    }
}

[Buggy Hunk]
args.forEach(builder::append);

[Patch]
args.forEach(a -> builder.append(a).append(" "));