Not.java

/*
 * Copyright © 2014 - 2021 Leipzig University (Database Research Group)
 *
 * Licensed 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.gradoop.flink.model.impl.functions.filters;

import org.apache.flink.api.common.functions.FilterFunction;

/**
 * A filter that inverts a filter by using a logical {@code not}.
 * This filter will therefore accept all objects that are not accepted by
 * the original filter.
 *
 * @param <T> The type of objects to filter.
 */
public class Not<T> extends AbstractRichCombinedFilterFunction<T> {

  /**
   * Constructor setting the filter to invert using a logical {@code not}.
   *
   * @param filter The filter.
   */
  public Not(FilterFunction<? super T> filter) {
    super(filter);
  }

  @Override
  public boolean filter(T value) throws Exception {
    return !components[0].filter(value);
  }
}