implementation 'com.squareup.retrofit2:retrofit:2.9.0'
implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
implementation 'com.squareup.retrofit2:adapter-rxjava2:2.9.0'
implementation 'io.reactivex.rxjava2:rxjava:2.2.21'
implementation 'io.reactivex.rxjava2:rxandroid:2.1.1'

public interface ApiService {
    @POST("user/login")
    Observable<Response<LoginResponse>> login(
        @Body LoginRequest loginRequest
    );
}

Retrofit retrofit = new Retrofit.Builder()
    .baseUrl("https://api.example.com/")
    .addConverterFactory(GsonConverterFactory.create())
    .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
    .build();

ApiService apiService = retrofit.create(ApiService.class);

public class LoginRequest {
    private String username;
    private String password;
    
    // 构造函数、getter和setter
}

public class LoginResponse {
    private String token;
    private User user;
    
    // getter和setter
}

LoginRequest loginRequest = new LoginRequest("username", "password");

apiService.login(loginRequest)
    .subscribeOn(Schedulers.io()) // 在IO线程执行网络请求
    .observeOn(AndroidSchedulers.mainThread()) // 在主线程处理结果
    .subscribe(new Observer<Response<LoginResponse>>() {
        @Override
        public void onSubscribe(Disposable d) {
            // 可以在这里显示加载进度条
        }

        @Override
        public void onNext(Response<LoginResponse> response) {
            if (response.isSuccessful()) {
                LoginResponse loginResponse = response.body();
                // 处理成功响应
            } else {
                // 处理错误响应
            }
        }

        @Override
        public void onError(Throwable e) {
            // 处理网络错误
        }

        @Override
        public void onComplete() {
            // 请求完成，可以隐藏加载进度条
        }
    });

apiService.login(loginRequest)
    .subscribeOn(Schedulers.io())
    .observeOn(AndroidSchedulers.mainThread())
    .subscribe(
        response -> {
            if (response.isSuccessful()) {
                // 处理成功响应
            } else {
                // 处理错误响应
            }
        },
        throwable -> {
            // 处理错误
        }
    );

@POST("user/login")
@Headers({
    "Content-Type: application/json",
    "Accept: application/json"
})
Observable<Response<LoginResponse>> login(@Body LoginRequest loginRequest);

@POST("user/login")
Observable<Response<LoginResponse>> login(
    @Header("Authorization") String authToken,
    @Body LoginRequest loginRequest
);