A binary search implementation. : Collections Search « Collections « Java Tutorial

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// ----------------------------------------------------------------------------
 * A binary search implementation.
public class BinarySearch {

  public int find(final int[] data, final int key) {
    int low = 0, high = data.length - 1;

    while (low <= high) {
      final int i = (low + high) >> 1;
      final int v = data[i];

      if (v == key)
        return i; // this line does not get covered unless there is a match
      else if (v < key)
        low = i + 1;
        // v > key
        high = i - 1;

    return -1;


9.41.Collections Search
9.41.1.Binary Searching
9.41.2.Check whether the given Collection contains the given element instance.
9.41.3.Binary search routines
9.41.4.Return the first element in 'candidates' that is contained in source
9.41.5.Find a value of the given type in the given Collection
9.41.6.Get the difference of two collections
9.41.7.A binary search implementation.