Question

（我从Esper跳到Siddhi）

我正在尝试在同一个流中部署多个查询。此处的示例https://docs.wso2.com/display/CEP400/Using+Siddhi+as+a+Library显示了如何在流中部署查询，完全在一个ExecutionPlan中。那么，如果我想将查询添加到同一个执行计划，同一个流？

，该怎么办？

我有兴趣用Java语言编写这个代码。

更新

我想在现有的执行计划中添加查询。这意味着当流到达时，而不是之前。使用发布为答案的示例：

SiddhiManager siddhiManager = new SiddhiManager();

String executionPlan = "" +
                       "@Plan:name('demo') " +
                       "" +
                       "define stream cseEventStream (symbol string, price float, volume long);" +
                       "" +
                       "from cseEventStream[symbol==\"WSO2\"] " +
                       "insert into wso2Stream;" +
                       "" +
                       "from cseEventStream[symbol==\"ABC\"] " +
                       "insert into abcStream;";

ExecutionPlanRuntime executionPlanRuntime = siddhiManager.createExecutionPlanRuntime(executionPlan);

StreamCallback streamCallback = new StreamCallback() {
    @Override
    public void receive(Event[] events) {
        EventPrinter.print(events);
    }
};

executionPlanRuntime.addCallback("wso2Stream", streamCallback);
//Similarly, we can add another call back for abcStream

streamCallback.startProcessing();

InputHandler inputHandler = executionPlanRuntime.getInputHandler("cseEventStream");

executionPlanRuntime.start();
// HERE: ADD new query <---------------------------------------------
inputHandler.send(new Object[]{"WSO2", 700f, 100l});
inputHandler.send(new Object[]{"ABC", 60.5f, 200l});
inputHandler.send(new Object[]{"WSO2", 60.5f, 200l});

streamCallback.stopProcessing();
executionPlanRuntime.shutdown();

Answer 1

以下示例在同一个执行计划中为同一个流（cseEventStream）添加多个查询。

SiddhiManager siddhiManager = new SiddhiManager();

String executionPlan = "" +
                       "@Plan:name('demo') " +
                       "" +
                       "define stream cseEventStream (symbol string, price float, volume long);" +
                       "" +
                       "from cseEventStream[symbol==\"WSO2\"] " +
                       "insert into wso2Stream;" +
                       "" +
                       "from cseEventStream[symbol==\"ABC\"] " +
                       "insert into abcStream;";

ExecutionPlanRuntime executionPlanRuntime = siddhiManager.createExecutionPlanRuntime(executionPlan);

StreamCallback streamCallback = new StreamCallback() {
    @Override
    public void receive(Event[] events) {
        EventPrinter.print(events);
    }
};

executionPlanRuntime.addCallback("wso2Stream", streamCallback);
//Similarly, we can add another call back for abcStream

streamCallback.startProcessing();

InputHandler inputHandler = executionPlanRuntime.getInputHandler("cseEventStream");

executionPlanRuntime.start();

inputHandler.send(new Object[]{"WSO2", 700f, 100l});
inputHandler.send(new Object[]{"ABC", 60.5f, 200l});
inputHandler.send(new Object[]{"WSO2", 60.5f, 200l});

streamCallback.stopProcessing();
executionPlanRuntime.shutdown();

我使用的是Siddhi版本3.0.6-beta2。

此代码示例是对Siddhi Passthrough test cases（PassThroughTest4）之一的修改。

更新

查看ExecutionPlanRuntime class，似乎无法在运行中添加查询＆＃34;。

因此，根据我的理解，您必须关闭当前的执行计划运行时，添加这些新查询并重新启动它。

Siddhi（作为图书馆）对Same Stream的许多查询

1 个答案:

更新