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Brownies Collections complements the Java Collections Framework. GapList combines the strengths of both ArrayList and LinkedList. BigList is a list optimized for storing large number of elements. There are specialized List implementations for all primitive data types (IntGapList, IntBigList, IntObjGapList, IntObjBigList). The key collection classes offer support for keys and constraints for lists and collections (KeyList, KeyCollection, KeySet, Key1List, Key1Collection, Key1Set, Key2List, Key2Collection, Key2Set).

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// ---
// --- DO NOT EDIT
// --- AUTOMATICALLY GENERATED FILE
// ---
/*
 * Copyright 2014 by Thomas Mauch
 *
 * 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.
 *
 * $Id: DoubleBinarySearch.java 3070 2015-12-30 22:58:20Z origo $
 */
package org.magicwerk.brownies.collections.helper.primitive;

import java.util.Collections;
import java.util.Comparator;
import java.util.List;

import org.magicwerk.brownies.collections.helper.ArraysHelper;
import org.magicwerk.brownies.collections.helper.NaturalComparator;
import org.magicwerk.brownies.collections.primitive.IDoubleList;


/**
 * Binary search for primitive type double.
 *
 * @author Thomas Mauch
 * @version $Id: DoubleBinarySearch.java 3070 2015-12-30 22:58:20Z origo $
 */
public class DoubleBinarySearch {
  /**
   * Searches the specified list for the specified object using the binary search algorithm. The
   * list must be sorted into ascending order according to the specified comparator (as by the
   * {@link Collections#sort(List, Comparator) Collections.sort(List, Comparator)} method), prior
   * to making this call. If it is not sorted, the results are undefined.
   *
   * This method runs in log(n) time on random-access lists, which offer near-constant-time
   * access to each list element.
   *
   * @param list 	the list to be searched.
   * @param key 	the value to be searched for.
   * @param lower 	lower bound of range to search
   * @param upper 	upper bound of range to search
   * @return 		the index of the search key, if it is contained in the list;
   *	       		otherwise, (-(insertion point) - 1).
   */
  public static int binarySearch(IDoubleList list, double key, int lower, int upper) {
    while (lower <= upper) {
      int middle = (lower + upper) >>> 1;
      int c = ArraysHelper.compare(key, list.get(middle));
      if (c < 0) {
        upper = middle - 1;
      } else if (c > 0) {
        lower = middle + 1;
      } else {
          // Of course, we have to use binary search to find the precise breakpoint...
          // Everything between lower and upper inclusive compares at <= 0.
          while (lower < upper) {
            middle = (lower + upper) >>> 1;
            c = ArraysHelper.compare(list.get(middle), key);
            if (c < 0) {
              lower = middle + 1;
            } else { // c == 0
              upper = middle;
            }
          }
          return lower;
      }
    }
    return ~lower;
  }
}