在Rxjava2中从Single.onErrorResumeNext启动可观察链

import io.reactivex.Single;
import io.reactivex.functions.Function;

public class RxJavaExample {
    public static void main(String[] args) {
        Single<String> primarySource = Single.error(new RuntimeException("Primary source failed"));

        Single<String> fallbackSource = Single.just("Fallback data");

        primarySource
            .onErrorResumeNext(new Function<Throwable, Single<? extends String>>() {
                @Override
                public Single<? extends String> apply(Throwable throwable) throws Exception {
                    System.out.println("Error occurred: " + throwable.getMessage());
                    return fallbackSource;
                }
            })
            .subscribe(
                data -> System.out.println("Received data: " + data),
                error -> System.out.println("Final error: " + error.getMessage())
            );
    }
}