首页 \ 问答 \ 好好利用风暴？(Good use of storm?)

好好利用风暴？(Good use of storm?)

java

 我一直在阅读关于风暴和玩风暴先锋的例子。  
 我认为我已经理解了这个概念，并且它适用于很多情况。 我有一个测试项目，我想要了解更多关于这个，但我想知道风暴是否真的适合这个。  
 我遇到的概念问题是'流'定义。 看起来风暴将作为订阅流并实时处理它的魅力起作用，但我没有真正的流，而是我想要处理的有限数据集。  
 我知道这里有一个hadoop，但我对Storm的实时功能以及Storm撰写的Nathan在谈话中提到的其他有趣点感兴趣。  
 所以我想知道，人们是否会写Spouts来调查非流式API，然后对结果进行比较以模拟流？  
 第二个重要的一点是，似乎风暴拓扑从未完成处理，直到中断，这再次不适用于我的情况。 我希望我的拓扑知道，一旦我有限的源数据列表完成，处理可以终止并且可以发出最终结果。  
 那么，这在风暴术语中是否有意义，还是我看错了东西？ 如果是这样，那么您对这种实时并行计算需求有什么替代方案？  
 谢谢！ 

I've been reading about Storm and playing around with the examples from storm-starter. 
I think I got the concept and it applies very well to many cases. I have a test project I want to do to learn more about this, but I'm wondering if Storm is really suited for this. 
The conceptual problem I'm having is with the 'streaming' definition. It seems that Storms will work as a charm subscribing to a stream and processing it in real time, but I don't really have a stream, but rather a finite collection of data that I want to process. 
I know there's hadoop for this, but I'm interested in the real time capabilities of Storm as well as other interesting points that Nathan, who wrote Storm, mentions in his talks. 
So I was wondering, do people write Spouts that poll non streaming APIs and then diff the results maybe to emulate a stream?  
The second important point is, it seems that Storm topologies never finish processing until interrupted, which again doesn't apply to my case. I would like my topology to know that once my finite list of source data is finished, the processing can terminate and a final result can be emitted.  
So, does that all make sense in Storm terms or am I looking at the wrong thing? If so, what alternatives do you propose for this sort of real time parallel computing needs? 
Thanks!

原文：https://stackoverflow.com/questions/9377600

更新时间：2021-12-04 10:12

最满意答案

 您将以下变量传递给您的方法：  
public static double compoundValueMethod(double savingAmount,
                                         double annualInterestRate,
                                         int NumberOfMonth)
 
 请注意，但在方法中使用静态变量numberOfMonth而不是传递的NumberOfMonth参数（Java中的变量名称区分大小写）。 numberOfMonth默认初始化为0 ，因此不输入for循环，方法返回0。  
 您应该消除静态变量并仅使用局部变量。 如果你首先这样做，你会得到一个编译错误，这将使你更容易找到你的错误。 

You are passing the following variables to your method : 
public static double compoundValueMethod(double savingAmount,
                                         double annualInterestRate,
                                         int NumberOfMonth)
 
Note but use the static variable numberOfMonth in your method instead of the passed NumberOfMonth parameter (variable names in Java are case sensitive). numberOfMonth is initialized to 0 by default, so your for loop is not entered and the method returns 0. 
You should eliminate the static variables and only use local variables. Had you done that in the first place, you'd get a compilation error which would make it much easier to find your bug.

好好利用风暴？(Good use of storm?)

最满意答案

相关问答

为什么这个方法总是产生0作为其返回值？(Why does this method always produce 0 as its return value?)[2023-03-14]

方法返回值的地址(Address of return value of method)[2023-07-31]

检索方法是否返回“null”，如果不能产生返回值，则抛出异常？(Should a retrieval method return 'null' or throw an exception when it can't produce the return value? [closed])[2022-02-12]

方法在遇到“返回”时不返回值的“if”(method not returning value when encountering “return” in an “if”)[2023-09-18]

我该如何为此方法返回值？(How can i return value for this method?)[2021-08-30]

使用@Produce方法的正确方法(Right way to use @Produce method)[2023-09-03]

封装方法没有参数和返回值(Encapsulate method without parameters and with return value)[2022-05-21]

返回值异步方法(return value asynchronous method)[2022-10-19]

方法返回值(Method return values)[2024-01-06]

如果方法抛出异常，则从方法返回值(Return value from a method if the method throws an exception)[2023-08-17]

相关文章

最新问答