使用Jakarta ClientBuilder调用第三方API时遭遇BlockingNotAllowedException

问题根源 #

你遇到的异常是因为fetchUserInfo方法里的同步HTTP调用（get(JSONObject.class)）在Vert.x事件循环线程上执行了阻塞IO操作，之前仅在控制器级别添加@Blocking/@NonBlocking注解无效，是因为实际执行阻塞逻辑的是WenTokenInfoResolver类的方法，控制器的注解无法覆盖这个独立类的方法执行线程。

解决方案 #

方案1：给阻塞方法/类添加@Blocking注解 #

直接在执行阻塞IO的fetchUserInfo方法或者整个WenTokenInfoResolver类上添加@io.smallrye.common.annotation.Blocking注解，让该方法被调度到Vert.x的工作线程池执行：

import io.smallrye.common.annotation.Blocking;
import static jakarta.ws.rs.core.HttpHeaders.AUTHORIZATION;
import jakarta.ws.rs.client.Client;
import jakarta.ws.rs.client.ClientBuilder;

public class WenTokenInfoResolver {
    private final Client client;

    public WenTokenInfoResolver() {
        client = ClientBuilder.newBuilder().register(JacksonFeature.class).build();
    }

    @Blocking
    public UserInfo fetchUserInfo(final String userToken) throws WenTokenInfoResolverFailureException {
        return UserInfo.fromResponse(client.target(ConfigHelper.wenBaseUrl)
                .path(ConfigHelper.wenInfoOAuth)
                .request()
                .header(AUTHORIZATION, "Bearer " + userToken)
                .get(JSONObject.class));
    }
}

方案2：改用异步HTTP调用（推荐） #

使用Jakarta Client的异步API，避免阻塞事件循环线程，无需添加@Blocking注解：

import java.util.concurrent.CompletionStage;
import static jakarta.ws.rs.core.HttpHeaders.AUTHORIZATION;
import jakarta.ws.rs.client.Client;
import jakarta.ws.rs.client.ClientBuilder;

public class WenTokenInfoResolver {
    private final Client client;

    public WenTokenInfoResolver() {
        client = ClientBuilder.newBuilder().register(JacksonFeature.class).build();
    }

    public CompletionStage<UserInfo> fetchUserInfo(final String userToken) {
        return client.target(ConfigHelper.wenBaseUrl)
                .path(ConfigHelper.wenInfoOAuth)
                .request()
                .header(AUTHORIZATION, "Bearer " + userToken)
                .rx() // 启用反应式异步API
                .get(JSONObject.class)
                .thenApply(UserInfo::fromResponse);
    }
}

调用该方法时，需处理CompletionStage的异步结果，比如在控制器方法中直接返回CompletionStage<UserInfo>，框架会自动处理异步调度。

方案3：使用Vert.x适配的Jakarta Client #

如果项目基于Quarkus等Vertx生态框架，推荐使用VertxClientBuilder创建客户端，更好适配Vert.x异步模型：

import io.vertx.mutiny.core.Vertx;
import io.vertx.mutiny.ext.web.WebClient;
import io.vertx.ext.web.client.WebClientOptions;
import jakarta.enterprise.context.ApplicationScoped;

@ApplicationScoped
public class WenTokenInfoResolver {
    private final WebClient webClient;

    public WenTokenInfoResolver(Vertx vertx) {
        this.webClient = WebClient.create(vertx, new WebClientOptions()
                .setDefaultHost(ConfigHelper.wenBaseUrl)
                .setDefaultPort(80)); // 根据实际服务端口调整
    }

    public Uni<UserInfo> fetchUserInfo(final String userToken) {
        return webClient.get(ConfigHelper.wenInfoOAuth)
                .putHeader(AUTHORIZATION, "Bearer " + userToken)
                .send()
                .onItem().transform(response -> {
                    JSONObject json = response.bodyAsJsonObject();
                    return UserInfo.fromResponse(json);
                });
    }
}

内容的提问来源于stack exchange，提问作者hemanth reddy m