项目管理

- 项目规划 - 前端 - 示例代码 ```js let a = 3 console.log(a) ``` - <h1 style="color: blue"> 你好 </h1> -  - java 代码 ```java public class TimestampWatermarkDemo { public static class Event { public String user; public long eventTime; public int value; public Event(){} public Event(String user, long eventTime, int value) { this.user = user; this.eventTime = eventTime; this.value = value; } public long getEventTime() { return eventTime; } @Override public String toString() { return "Event{" + "user='" + user + '\'' + ", eventTime=" + eventTime + ", value=" + value + '}'; } } public static void main(String[] args) throws Exception { StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment(); DataStream<Event> source = env.fromElements( new Event("alice", 1000L, 1), new Event("alice", 4000L, 1), new Event("alice", 3000L, 1), new Event("bob", 8000L, 1), new Event("alice", 12000L, 1) ); WatermarkStrategy<Event> wmStrategy = WatermarkStrategy.<Event>forBoundedOutOfOrderness(Duration.ofSeconds(5)) .withTimestampAssigner((event, recordTimestamp) -> event.getEventTime()); DataStream<Event> withWaterMark = source.assignTimestampsAndWatermarks(wmStrategy); withWaterMark.print(); env.execute("timestamp-water-mark-demo"); } } ``` - 1 let a = 3