使用 lombok.Getter(lazy = true) 和 java 10 的不兼容类型错误

Question

I'm trying to do some caching using reactor , reactor.ipc.netty.http.client.HttpClient and initialize it as lazy getter field with lombok's @Getter(lazy = true) .

All works fine with Java 8 but fails to compile with error: incompatible types: Duration cannot be converted to String with Java 10 on this snippet

@Value
public static class Translations {

    Map<String, Translation> translations;

    @Value
    public static class Translation {

        Map<String, String> content;

    }
}

@Getter(lazy = true)
Mono<Map<String, Translations.Translation>> translations = httpClient
        .get(String.format("%s/translations/%s", endpoint, translationGroup), Function.identity())
        .flatMap(it -> it.receive().aggregate().asByteArray())
        .map(byteArray -> {
            try {
                return objectMapper.readValue(byteArray, Translations.class);
            } catch (IOException e) {
                throw new UncheckedIOException("Failed to get translation for " + translationGroup, e);
            }
        })
        .map(Translations::getTranslations)
        .retryWhen(it -> it.delayElements(Duration.ofMillis(200)))
        .cache(Duration.ofMinutes(5))
        .timeout(Duration.ofSeconds(10));

but it compiles perfectly fine with

@Getter(lazy = true)
Mono<Map<String, Translations.Translation>> translations = Mono.just(new byte[]{})
        .map(byteArray -> {
            try {
                return objectMapper.readValue(byteArray, Translations.class);
            } catch (IOException e) {
                throw new UncheckedIOException("Failed to get translation for " + translationGroup, e);
            }
        })
        .map(Translations::getTranslations)
        .retryWhen(it -> it.delayElements(Duration.ofMillis(200)))
        .cache(Duration.ofMinutes(5))
        .timeout(Duration.ofSeconds(10));

How to know what's wrong and how its possible to workaround?

Answer 1

I suggest to move the initialization code to a separate method.

@Getter(lazy=true)
SomeType t = <complicatedInitializationCode>;

becomes

@Getter(lazy=true)
SomeType t = initializeT();

private SomeType initializeT() {
    return <complicatedInitializationCode>;
}

Disclosure: I am a lombok developer.