getUdfEngineVariable

getUdfEngineVariable(engine, name)

engine 字符串标量，流图中由 DStream::udfEngine 创建的自定义引擎名称。

name 字符串标量，外部变量名称，需为创建 DStream::udfEngine 时 variableNames 中定义的变量之一。

查询指定 DStream::udfEngine 中指定外部变量的当前值。

返回值：指定变量当前的值，类型和形式取决于变量本身。

def callTimes(mutable cnt, msg) {
    cnt += 1;
    return msg
}
g = createStreamGraph("indicators")
g.source("trade", 1024:0, `price`volume, [DOUBLE,INT])
    .udfEngine(callTimes, [`price,`volume] ,[`number], [5])
    .setEngineName("udf")
    .sink("output111")
g.submit()
go
n = 1000
price = rand(100, n)
volume = rand(1000, n)
t = table(price, volume)
appendOrcaStreamTable("trade", t)
// 获取当前 number 的值
useOrcaStreamEngine("udf", getUdfEngineVariable, "number")
// output: 1005

相关函数：DStream::udfEngine