技術標籤：Flink

預設間隔是200ms

(1) 在 StreamExecutionEnvironmennt的方法有體現

@PublicEvolving
public void setStreamTimeCharacteristic(TimeCharacteristic characteristic) {
	this.timeCharacteristic = Preconditions.checkNotNull(characteristic);
	if (characteristic == TimeCharacteristic.ProcessingTime) {
		getConfig(
 
).setAutoWatermarkInterval(0);
	} else {
		getConfig().setAutoWatermarkInterval(200);
	}
}

如果要修改這個WatermarkInterval時間：

（2）org.apache.flink.api.common.ExecutionConfig:

private long autoWatermarkInterval = 200;

// 可以通過這個方法來修改預設的WatermarkInterval

/**
 * Sets the interval of the automatic watermark emission. Watermarks are used throughout
 * the streaming system to keep track of the progress of time. They are used, for example,
 * for time based windowing.
 *
 * <p>Setting an interval of {@code 0} will disable periodic watermark emission.
 *
 * @param interval The interval between watermarks in milliseconds.
 */
 

   @PublicEvolving
   public ExecutionConfig setAutoWatermarkInterval(long interval) {
       Preconditions.checkArgument(interval >= 0, "Auto watermark interval must not be negative.");
       this.autoWatermarkInterval = interval;
       return this;
   }