[大数据]Flink之project

作用

主要是用于获取元组中指定字段的值，注意只能用于元组，不能用在其他数据类型。

代码

    public static void main(String[] args) throws Exception {
        StreamExecutionEnvironment executionEnvironment = StreamExecutionEnvironment.getExecutionEnvironment();
        executionEnvironment.setParallelism(1);
        DataStream<Tuple3<String,Integer,Double>> dataStream1 = executionEnvironment.fromCollection(Arrays.asList(
                new Tuple3<String,Integer,Double>("sensor_1", 1547718199, 35.8),
                new Tuple3<String,Integer,Double>("sensor_6", 1547718201, 15.4),
                new Tuple3<String,Integer,Double>("sensor_7", 1547718202, 6.7),
                new Tuple3<String,Integer,Double>("sensor_6", 1547718203, 15.9),
                new Tuple3<String,Integer,Double>("sensor_10", 1547718205, 38.1),
                new Tuple3<String,Integer,Double>("sensor_6", 1547718206, 15.1),
                new Tuple3<String,Integer,Double>("sensor_6", 1547718209, 15.0)
        ));
        SingleOutputStreamOperator<Tuple> projectStream = dataStream1.project(0, 2);
        projectStream.print();

结果：

(sensor_1,35.8)
(sensor_6,15.4)
(sensor_7,6.7)
(sensor_6,15.9)
(sensor_10,38.1)
(sensor_6,15.1)
(sensor_6,15.0)

Process finished with exit code 0