[Demonstration 1]

[Buggy Method]
public static void main(String[] args) {
    if (args.length < 2) {
        System.out.println("Usage: java Server <address> <port>");
        //										0         1
        return;
    }
    int port = Integer.parseInt(args[1]);
    try {
        server = HttpServer.create(new InetSocketAddress(InetAddress.getByName(args[0]), port), 0);
    } catch (IOException e) {
        System.out.println("@Server:error creating server: " + e);
        e.printStackTrace();
    }
    /* Create database - automatically populated */
    users = new Database();
    server.createContext("/login", new LoginHandler());
    server.createContext("/signup", new SignupHandler());
    server.setExecutor(null);
    server.start();
}

[Buggy Hunk]
users = new Database();

[Patch]
db = new Database();

[Demonstration 2]

[Buggy Method]
@Override
public void run() {
    try {
        ServerSocket socket = new ServerSocket(thePort);
    } catch (IOException e) {
        e.printStackTrace();
    }
}

[Buggy Hunk]
ServerSocket socket = new ServerSocket(thePort);

[Patch]
ServerSocket socket = new ServerSocket(port);

[Demonstration 3]

[Buggy Method]
@RequestMapping("/delete")
@ResponseBody
public Result delete(Long id) {
    Result result = new Result();
    try {
        peopleJobService.deletePeopleJobById(id);
        result.setMsg("删除职级成功！");
        result.setSuccess(true);
        return result;
    } catch (RuntimeException e) {
        LOGGER.error("删除职级失败：{}", e);
        result.setMsg(e.getMessage());
        return result;
    }
}

[Buggy Hunk]
}catch(RuntimeException e){

[Patch]
}catch(Throwable e){