weiss.util
Class Arrays

java.lang.Object
  |
  +--weiss.util.Arrays

public class Arrays

extends java.lang.Object

Instanceless class that contains static methods to manipulate arrays.

Method Summary

static int	binarySearch(java.lang.Object[] arr, java.lang.Object x) Performs a search on sorted array arr.
static int	binarySearch(java.lang.Object[] arr, java.lang.Object x, Comparator cmp) Performs a search on sorted array arr using a comparator.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

binarySearch

public static int binarySearch(java.lang.Object[] arr,
                               java.lang.Object x)

Performs a search on sorted array arr. If arr is not sorted, results are undefined. Implicitly, this assumes that all objects are Comparable.

Parameters:

arr - the array to search.

x - the object to search for.

Returns:

if x is found, returns the index where it is found. otherwise, x is not found. In that case, a negative number is always returned, and this number is equal to -( p + 1 ), which p is the first position greater than x. This can range from -1 down to -(arr.length+1).

Throws:

java.lang.ClassCastException - if comparsions cannot be performed.

binarySearch

public static int binarySearch(java.lang.Object[] arr,
                               java.lang.Object x,
                               Comparator cmp)

Performs a search on sorted array arr using a comparator. If arr is not sorted, results are undefined.

Parameters:

arr - the array to search.

x - the object to search for.

cmp - the comparator.

Returns:

if x is found, returns the index where it is found. otherwise, x is not found. In that case, a negative number is always returned, and this number is equal to -( p + 1 ), which p is the first position greater than x. This can range from -1 down to -(arr.length+1).

Throws:

java.lang.ClassCastException - if comparsions cannot be performed.