Class ArrayUtility

java.lang.Object

ArrayUtility

public class ArrayUtility
extends java.lang.Object

This class provides methods that duplicate the functionality of ArrayList but without the space and lookup overhead of double indirection. It only supports arrays of ints. Premature optimization? It's actually here because I didn't know 1301 covered ArrayList, so shut up.

Note that this class is wildly time-inefficient and unsuitable for use with anything but the smallest arrays. Unlike ArrayList, which uses exponential doubling of allocated arrays, these methods specify a system in which the array is reallocated at every addition and deletion. This is necessary because the length field has to always be exact so that students can rely on it.

Constructor Summary

Constructors

Constructor and Description
ArrayUtility()

Method Summary

Methods

Modifier and Type	Method and Description
static int[]	addElement(int[] current, int elem) Add element to array
static int[]	deleteElement(int[] current, int index) Delete array element
static int	linearSearch(int[] current, int value) Linear search: Find first occurrence of value in array, return index

Methods inherited from class java.lang.Object

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

Constructor Detail

ArrayUtility

public ArrayUtility()

Method Detail

addElement

public static int[] addElement(int[] current,
               int elem)

Add element to array

Parameters:

current - array to duplicate and add element

elem - element to add

Returns:

new array 1 element larger with elem appended

deleteElement

public static int[] deleteElement(int[] current,
                  int index)

Delete array element

Parameters:

current - array with element to delete

index - index of element to delete

Returns:

new array with element at index deleted

linearSearch

public static int linearSearch(int[] current,
               int value)

Linear search: Find first occurrence of value in array, return index

Parameters:

current - array

value - value to find

Returns:

index if found, -1 if not