/*
* 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.api.common.aggregators;
import org.apache.flink.annotation.PublicEvolving;
import org.apache.flink.types.DoubleValue;
/**
* A {@link ConvergenceCriterion} over an {@link Aggregator} that defines convergence as reached once the aggregator
* holds the value zero. The aggregated data type is a {@link DoubleValue}.
*/
@SuppressWarnings("serial")
@PublicEvolving
public class DoubleZeroConvergence implements ConvergenceCriterion<DoubleValue> {
/**
* Returns true, if the aggregator value is zero, false otherwise.
*
* @param iteration The number of the iteration superstep. Ignored in this case.
* @param value The aggregator value, which is compared to zero.
* @return True, if the aggregator value is zero, false otherwise.
*/
@Override
public boolean isConverged(int iteration, DoubleValue value) {
return value.getValue() == 0;
}
}