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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: FloatBinarySearch.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.IFloatList;
/**
* Binary search for primitive type float.
*
* @author Thomas Mauch
* @version $Id: FloatBinarySearch.java 3070 2015-12-30 22:58:20Z origo $
*/
public class FloatBinarySearch {
/**
* 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(IFloatList list, float 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;
}
}