java - Retrofit2，maven项目，非法反射访问警告

Question

我刚刚开始一个新的Maven项目，并对Retrofit客户端进行了简单的实现。我收到以下警告:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by retrofit2.Platform (file:/C:/Users/Admin/.m2/repository/com/squareup/retrofit2/retrofit/2.8.1/retrofit-2.8.1.jar) to constructor java.lang.invoke.MethodHandles$Lookup(java.lang.Class,int)
WARNING: Please consider reporting this to the maintainers of retrofit2.Platform
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
Process finished with exit code 0

这是代码

import retrofit2.Retrofit;
import retrofit2.SimpleXmlConverterFactory;
import retrofit2.adapter.rxjava2.RxJava2CallAdapterFactory;

public class RetrofitClient {

    private static Retrofit retrofit = null;
    private RetrofitClient() { }

    public static EndPoints getAPI(String baseUrl) {
        if (retrofit == null) {
            retrofit = new Retrofit.Builder()
                    .baseUrl(baseUrl)
                    .addConverterFactory(SimpleXmlConverterFactory.create())
                    .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
                    .build();
        }
        return retrofit.create(EndPoints.class);
    }
}

界面简单

import retrofit2.Call;
import retrofit2.http.GET;

public interface EndPoints {
    @GET("teststatuses")
    Call<String> testStatus();
}

调用看起来像这样:

EndPoints endPoints = RetrofitClient.getAPI("http://localhost:8080/");
Call<String> repos = endPoints.testStatus();
System.out.println(repos.execute());

该项目使用SDK 11运行Java语言级别11

Answer 1

有一个issue归档，改造维护者之一对此做出了回应:

The reflection works around a bug in the JDK which was fixed in 14 but it's only used for default methods. As it's only a warning, it's not preventing your call from working.

因此，您可以选择

坚持使用Retrofit 2.8.x，并且

忽略警告，或

升级到Java 14

降级为Retrofit 2.7。*