vertx中的并行/并发调用

时间:2019-07-11 11:10:38

标签: java asynchronous vert.x

我正在后端(垂直代码)从数据库中读取数据,并且每一行都有一个url,我将在该URL上对状态字段执行“ GET” http请求,以作为响应,我将其存储回数据库并发送到UI。

CreateRequests方法发出http请求。我想同时执行。

        List<Future> toComplete=new ArrayList<>();
        Vertx vertx = Vertx.vertx();int i;
        for(i=0;i<requestsListInDept.size();i++)
        {
            String reqtype = requestsListInDept.getString(i);
            JsonObject requestProperties = dataReader.getRequestProperties(dept,reqtype);
           toComplete.add(Future.future());
           int currrent=i;
            vertx.executeBlocking(future->{
                System.out.println("calling for ");
                String individualResponse  = accReq.createRequests(requestContext,reqtype,empid,requestProperties);
               toComplete.get(currrent).complete(individualResponse);
                future.complete(individualResponse);
            },false,res->{
                JsonArray obj=new JsonArray( (res.result()).toString() );
                for(int index=0;index<obj.size();index++)
                {
                    JsonObject requestResponse=obj.getJsonObject(index);
                    response.add(requestResponse);

                }
                toComplete.get(currrent).complete(res.result());
            });
        }
      CompositeFuture.all(toComplete).setHandler(e -> {
                String collect = e.result()
                        .list()
                        .stream()
                        .map(Object::toString)
                        .collect(Collectors.joining(" ------- "));
                System.out.println(collect);
            });

return ;

如何有效地进行并发的get调用并合并响应(我将发送到UI的响应)并将它们存储回数据库

我正在循环所有URL并在循环中进行get请求。如果有大数据,我将得到Timeout(很明显)

1 个答案:

答案 0 :(得分:0)

Vert.x使用反应堆模式,因此使用该模式而不是多线程和executeBlocking可以获得类似的结果。仅在没有方法支持该模式(意味着没有异步方法)时才建议在Vert.x中使用多线程和阻塞调用。

也许这个例子可以帮助您

  public void doCall() {
    List<Future> toComplete = new ArrayList<>();
    WebClientOptions options = new WebClientOptions().setSsl(true);
    WebClient webClient = WebClient.create(Vertx.vertx(), options);
    IntStream.range(0, 15).forEach(counter -> {
      toComplete.add(Future.future());
      int current = counter;
      webClient.get(443, "google.com", "/")
               .send(httpResponseAsyncResult -> {
                 String googleResult = httpResponseAsyncResult.result().bodyAsString();
                 toComplete.get(current).complete(googleResult);
               });
      System.out.println("Calling google: times " + ++counter);
    });
    CompositeFuture.all(toComplete).setHandler(e -> {
      String collect = e.result()
                        .list()
                        .stream()
                        .map(Object::toString)
                        .collect(Collectors.joining(" ------- "));
      System.out.println(collect);
    });
  }

希望这会有所帮助