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package com.hao.chapter11;
import com.hao.chapter05.ClickSource;
import com.hao.chapter05.Event;
import org.apache.flink.api.common.eventtime.SerializableTimestampAssigner;
import org.apache.flink.api.common.eventtime.WatermarkStrategy;
import org.apache.flink.streaming.api.datastream.DataStream;
import org.apache.flink.streaming.api.environment.StreamExecutionEnvironment;
import org.apache.flink.table.api.Table;
import org.apache.flink.table.api.bridge.java.StreamTableEnvironment;
import java.time.Duration;
import static org.apache.flink.table.api.Expressions.$;
public class EventTimeTest {
public static void main(String[] args) throws Exception {
StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
env.setParallelism(1);
StreamTableEnvironment tableEnv = StreamTableEnvironment.create(env);
//1.在创建表的DDL中直接定义时间属性
String creatDDL = "CREATE TABLE clickTable (" +
"user_name STRING," +
"url STRING," +
"ts BIGINT," +
"et AS TO_TIMESTAMP( FROM_UNIXTIME(ts / 1000))," + //事件时间 FROM_UNIXTIME() 能转换为年月日时分秒这样的格式 转换秒
"WATERMARK FOR et AS et - INTERVAL '1' SECOND" + //watermark 延迟一秒
")WITH(" +
" 'connector' = 'filesystem'," +
" 'path' = 'input/clicks.txt'," +
" 'format' = 'csv'" +
")";
tableEnv.executeSql(creatDDL);
//2.在数据流中转换表定义时间属性
DataStream<Event> eventStream = env.addSource(new ClickSource())
.assignTimestampsAndWatermarks(WatermarkStrategy.<Event>forBoundedOutOfOrderness(Duration.ZERO)
.withTimestampAssigner(new SerializableTimestampAssigner<Event>() {
@Override
public long extractTimestamp(Event element, long recordTimestamp) {
return element.timestamp;
}
}));
Table eventTable = tableEnv.fromDataStream(eventStream, $("user"), $("url"), $("timestamp").as("ts")
, $("et").rowtime());
eventTable.printSchema();
env.execute();
}
}
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