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通过反射执行java方法

今天想实现一个功能就是通过一个交互式的环境，执行java函数。

通过Cmd类来定义函数

通过一个Executor类来注册命令并且执行命令

Cmd.class

public class Cmd {

    public static Response hello(Request request) {

        return Response.success("hello " + request.getParams().get(0));

    @Data

    public static class Request {

        private MapleCharacter player;

        private List<String> params;

    @Builder

    @Data

    public static class Response {

        private boolean success;

        private String message;

        public static Response success() {

            return Response.builder().success(true).message("执行成功").build();

        public static Response success(String message) {

            return Response.builder().success(true).message(message).build();

CmdExecutor.class

public class CmdExecutor {

    private static final Map<String, Method> methodMap = new HashMap<>();

    public static void init() {

        StringBuilder sb = new StringBuilder();

        Class<Cmd> cmdClass = Cmd.class;

        for (Method method : cmdClass.getMethods()) {

            Parameter[] parameters = method.getParameters();

            Class<?> returnType = method.getReturnType();

            if (parameters.length == 1 && parameters[0].getType()

                                                       .equals(Cmd.Request.class) && returnType.equals(Cmd.Response.class)) {

                sb.append(method.getName()).append(",");

                methodMap.put(method.getName().toLowerCase(), method);

        System.out.printf("注册命令: %s%n", sb);

    public static void execute(String cmdLine) {

        String[] splitCmd = cmdLine.split(" ");

        List<String> stringList = Arrays.asList(splitCmd);

        String cmd = stringList.get(0).toLowerCase();

        List<String> params = stringList.subList(1, stringList.size());

        Method method = methodMap.get(cmd);

        if (Objects.isNull(method)) {

            System.out.printf("命令不存在: %s%n", cmd);

        Cmd.Request request = new Cmd.Request();

        request.setPlayer(null);

        request.setParams(params);

        try {

            Cmd.Response response = (Cmd.Response) method.invoke(null, request);

            System.out.printf("执行结果: %s%n", response.getMessage());

        } catch (IllegalAccessException | InvocationTargetException e) {

            throw new RuntimeException(e);

    public static void main(String[] args) {

        init();

        execute("hello java");

执行结果：

注册命令: hello,

执行结果: hello java