org.opennms.core.utils
Class CollectionMath

java.lang.Object
  org.opennms.core.utils.CollectionMath

public class CollectionMath
extends Object

CollectionMath class.

Version:

$Id: $

Author:

Benjamin Reed

Constructor Summary

CollectionMath()

Method Summary

static Number	average(List<? extends Number> list) Get the average of the contents of a List of Number values, excluding null entries
static long	countNotNull(List list) Get the number of non-null entries in a List
static long	countNull(List list) Get the number of null entries in a List
static Number	median(List<? extends Number> list) Get the median of the contents of a List of Number values, excluding null entries
static Number	percentNotNull(List<? extends Number> list) Get the percentage of not-null entries in a List of Number values
static Number	percentNull(List<? extends Number> list) Get the percentage of null entries in a List of Number values

Methods inherited from class java.lang.Object

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

Constructor Detail

CollectionMath

public CollectionMath()

Method Detail

countNull

public static long countNull(List list)

Get the number of null entries in a List

Parameters:

list - the List

Returns:

the number of null entries

countNotNull

public static long countNotNull(List list)

Get the number of non-null entries in a List

Parameters:

list - the list

Returns:

the number of non-null entries

percentNull

public static Number percentNull(List<? extends Number> list)

Get the percentage of null entries in a List of Number values

Parameters:

list - the List of Number values

Returns:

the percentage of null values as a Number value

percentNotNull

public static Number percentNotNull(List<? extends Number> list)

Get the percentage of not-null entries in a List of Number values

Parameters:

list - the List of Number values

Returns:

the percentage of not-null values as a Number value

average

public static Number average(List<? extends Number> list)

Get the average of the contents of a List of Number values, excluding null entries

Parameters:

list - the List of Number values

Returns:

the average of the not-null values as a Number value

median

public static Number median(List<? extends Number> list)

Get the median of the contents of a List of Number values, excluding null entries

Parameters:

list - the List of Number values

Returns:

the median of the not-null values as a Number value