org.melati.poem.util

Class ArrayUtils

java.lang.Object

org.melati.poem.util.ArrayUtils

public final class ArrayUtils
extends Object

A collection of useful operations on Arrays.

Method Summary

Modifier and Type	Method and Description
static Object[]	added(Object[] xs, Object y) Add an Object to an Array.
static Object[]	arrayOf(Enumeration<Object> e) Create an Array from an Enumeration.
static <T> T[]	arrayOf(Vector<T> v) Create an Array from a Vector.
static Object[]	concatenated(Object[] xs, Object[] ys) Create a new Array from two Arrays.
static boolean	contains(Object[] xs, Object x) Whether an Array contains an Object.
static int	indexOf(Object[] xs, Object x) Lookup the first instance of an Object in an Array.
static Object[]	removed(Object[] xs, Object y) Remove an Object from an Array.
static Object[]	section(Object[] xs, int start, int limit) Extract a subsection of an Array.

Methods inherited from class java.lang.Object

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

Method Detail

arrayOf

public static <T> T[] arrayOf(Vector<T> v)

Create an Array from a Vector.

Parameters:

v - the Vector

Returns:

the Array

arrayOf

public static Object[] arrayOf(Enumeration<Object> e)

Create an Array from an Enumeration.

Parameters:

e - the Enumeration

Returns:

the Array

added

public static Object[] added(Object[] xs,
                             Object y)

Add an Object to an Array.

Parameters:

xs - the array to add to

y - the object to add

Returns:

the enlarged array

removed

public static Object[] removed(Object[] xs,
                               Object y)

Remove an Object from an Array.

Parameters:

xs - the array to remove from

y - the object to remove

Returns:

the reduced array

concatenated

public static Object[] concatenated(Object[] xs,
                                    Object[] ys)

Create a new Array from two Arrays.

Parameters:

xs - first Array

ys - second Array

Returns:

a new Array with the elements of the second appended to the first

section

public static Object[] section(Object[] xs,
                               int start,
                               int limit)

Extract a subsection of an Array.

Parameters:

xs - the input Array

start - the index in the original array to start our section, inclusive

limit - the index in the original array to stop at, inclusive

Returns:

the new Array

indexOf

public static int indexOf(Object[] xs,
                          Object x)

Lookup the first instance of an Object in an Array.

Parameters:

xs - the Array to search

x - the Object to check

Returns:

the index of the first equal object

contains

public static boolean contains(Object[] xs,
                               Object x)

Whether an Array contains an Object.

Parameters:

xs - the Array to search

x - the Object to check

Returns:

whether it is there or not