content: /*
   * 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.calcite.runtime;
  
  import com.google.common.collect.Ordering;
  
  import java.util.Collections;
  import java.util.Comparator;
  
  /**
   * Compares arrays.
   */
  public class ArrayComparator implements Comparator<Object[]> {
    private final Comparator[] comparators;
  
    public ArrayComparator(Comparator... comparators) {
      this.comparators = comparators;
    }
  
    public ArrayComparator(boolean... descendings) {
      this.comparators = comparators(descendings);
    }
  
    private static Comparator[] comparators(boolean[] descendings) {
      Comparator[] comparators = new Comparator[descendings.length];
      for (int i = 0; i < descendings.length; i++) {
        boolean descending = descendings[i];
        comparators[i] =
            descending
                ? Collections.reverseOrder()
                : Ordering.natural();
      }
      return comparators;
    }
  
    @Override public int compare(Object[] o1, Object[] o2) {
      for (int i = 0; i < comparators.length; i++) {
        Comparator comparator = comparators[i];
        int c = comparator.compare(o1[i], o2[i]);
        if (c != 0) {
          return c;
        }
      }
      return 0;
    }
  }
  