org.apache.flink.streaming.api.TimerService Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.flink.streaming.api;
import org.apache.flink.annotation.PublicEvolving;
/**
* Interface for working with time and timers.
*/
@PublicEvolving
public interface TimerService {
/** Error string for {@link UnsupportedOperationException} on registering timers. */
String UNSUPPORTED_REGISTER_TIMER_MSG = "Setting timers is only supported on a keyed streams.";
/** Error string for {@link UnsupportedOperationException} on deleting timers. */
String UNSUPPORTED_DELETE_TIMER_MSG = "Deleting timers is only supported on a keyed streams.";
/** Returns the current processing time. */
long currentProcessingTime();
/** Returns the current event-time watermark. */
long currentWatermark();
/**
* Registers a timer to be fired when processing time passes the given time.
*
* Timers can internally be scoped to keys and/or windows. When you set a timer
* in a keyed context, such as in an operation on
* {@link org.apache.flink.streaming.api.datastream.KeyedStream} then that context
* will also be active when you receive the timer notification.
*/
void registerProcessingTimeTimer(long time);
/**
* Registers a timer to be fired when the event time watermark passes the given time.
*
*
Timers can internally be scoped to keys and/or windows. When you set a timer
* in a keyed context, such as in an operation on
* {@link org.apache.flink.streaming.api.datastream.KeyedStream} then that context
* will also be active when you receive the timer notification.
*/
void registerEventTimeTimer(long time);
/**
* Deletes the processing-time timer with the given trigger time. This method has only an effect if such a timer
* was previously registered and did not already expire.
*
*
Timers can internally be scoped to keys and/or windows. When you delete a timer,
* it is removed from the current keyed context.
*/
void deleteProcessingTimeTimer(long time);
/**
* Deletes the event-time timer with the given trigger time. This method has only an effect if such a timer
* was previously registered and did not already expire.
*
*
Timers can internally be scoped to keys and/or windows. When you delete a timer,
* it is removed from the current keyed context.
*/
void deleteEventTimeTimer(long time);
}