org.apache.flink.runtime.state.DoneFuture 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.runtime.state;
import javax.annotation.Nullable;
import java.util.concurrent.Future;
import java.util.concurrent.RunnableFuture;
import java.util.concurrent.TimeUnit;
/**
* A {@link Future} that is always done and will just yield the object that was given at creation
* time.
*
* @param The type of object in this {@code Future}.
*/
public class DoneFuture implements RunnableFuture {
@Nullable
private final T payload;
protected DoneFuture(@Nullable T payload) {
this.payload = payload;
}
@Override
public boolean cancel(boolean mayInterruptIfRunning) {
return false;
}
@Override
public boolean isCancelled() {
return false;
}
@Override
public boolean isDone() {
return true;
}
@Override
public T get() {
return payload;
}
@Override
public T get(
long timeout,
TimeUnit unit) {
return get();
}
@Override
public void run() {
}
public static DoneFuture of(@Nullable T result) {
return new DoneFuture<>(result);
}
}