com.aoindustries.util

Class AoArrays

java.lang.Object

com.aoindustries.util.AoArrays

public class AoArrays
extends Object

General-purpose array utilities and constants.

Author:

AO Industries, Inc.

Field Summary

Fields

Modifier and Type	Field and Description
static byte[]	EMPTY_BYTE_ARRAY
static char[]	EMPTY_CHAR_ARRAY
static Class<?>[]	EMPTY_CLASS_ARRAY
static int[]	EMPTY_INT_ARRAY
static long[]	EMPTY_LONG_ARRAY
static Object[]	EMPTY_OBJECT_ARRAY
static Serializable[]	EMPTY_SERIALIZABLE_ARRAY
static String[]	EMPTY_STRING_ARRAY

Method Summary

Modifier and Type	Method and Description
static boolean	allEquals(byte[] b, int off, int len, byte value) Checks if all the values in the provided range are equal to value.
static <E> Set<E>	asUnmodifiableSet(E... array) Gets an unmodifiable set view with the contents of a backing array.
static int	compare(byte[] ba1, byte[] ba2) Compares two byte[].
static boolean	equals(byte[] b1, byte[] b2, int off, int len) Checks if the subrange of two byte arrays is equal.
static boolean	equals(byte[] b1, int off1, byte[] b2, int off2, int len) Checks if the subrange of two byte arrays is equal.
static int	hashCode(byte[] a, int off, int len) Computes hashCode compatible with Arrays.hashCode, but only across the given subset of the array.
static int	indexOf(byte[] array, byte element) Finds the first index of an element or -1 if not found.
static int	indexOf(byte[] array, byte element, int fromIndex) Finds the first index of an element or -1 if not found.
static int	indexOf(char[] array, char element) Finds the first index of an element or -1 if not found.
static int	indexOf(char[] array, char element, int fromIndex) Finds the first index of an element or -1 if not found.
static int	indexOf(double[] array, double element) Finds the first index of an element or -1 if not found.
static int	indexOf(double[] array, double element, int fromIndex) Finds the first index of an element or -1 if not found.
static <E> int	indexOf(E[] array, E element) Finds the first index of an element or -1 if not found.
static <E extends Enum<E>> int	indexOf(E[] array, E element) Finds the first index of an element or -1 if not found.
static <E> int	indexOf(E[] array, E element, int fromIndex) Finds the first index of an element or -1 if not found.
static <E extends Enum<E>> int	indexOf(E[] array, E element, int fromIndex) Finds the first index of an element or -1 if not found.
static int	indexOf(float[] array, float element) Finds the first index of an element or -1 if not found.
static int	indexOf(float[] array, float element, int fromIndex) Finds the first index of an element or -1 if not found.
static int	indexOf(int[] array, int element) Finds the first index of an element or -1 if not found.
static int	indexOf(int[] array, int element, int fromIndex) Finds the first index of an element or -1 if not found.
static int	indexOf(long[] array, long element) Finds the first index of an element or -1 if not found.
static int	indexOf(long[] array, long element, int fromIndex) Finds the first index of an element or -1 if not found.
static int	indexOf(short[] array, short element) Finds the first index of an element or -1 if not found.
static int	indexOf(short[] array, short element, int fromIndex) Finds the first index of an element or -1 if not found.
static int	lastIndexOf(byte[] array, byte element) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(byte[] array, byte element, int fromIndex) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(char[] array, char element) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(char[] array, char element, int fromIndex) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(double[] array, double element) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(double[] array, double element, int fromIndex) Finds the last index of an element or -1 if not found.
static <E> int	lastIndexOf(E[] array, E element) Finds the last index of an element or -1 if not found.
static <E extends Enum<E>> int	lastIndexOf(E[] array, E element) Finds the last index of an element or -1 if not found.
static <E> int	lastIndexOf(E[] array, E element, int fromIndex) Finds the last index of an element or -1 if not found.
static <E extends Enum<E>> int	lastIndexOf(E[] array, E element, int fromIndex) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(float[] array, float element) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(float[] array, float element, int fromIndex) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(int[] array, int element) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(int[] array, int element, int fromIndex) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(long[] array, long element) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(long[] array, long element, int fromIndex) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(short[] array, short element) Finds the last index of an element or -1 if not found.
static int	lastIndexOf(short[] array, short element, int fromIndex) Finds the last index of an element or -1 if not found.
static <V> V[]	merge(Class<V> clazz, Collection<? extends Collection<? extends V>> collections, Comparator<? super V> comparator) Merges multiple already-sorted collections into one big array.

Methods inherited from class java.lang.Object

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

Field Detail

EMPTY_BYTE_ARRAY

public static final byte[] EMPTY_BYTE_ARRAY

EMPTY_CHAR_ARRAY

public static final char[] EMPTY_CHAR_ARRAY

EMPTY_INT_ARRAY

public static final int[] EMPTY_INT_ARRAY

EMPTY_LONG_ARRAY

public static final long[] EMPTY_LONG_ARRAY

EMPTY_CLASS_ARRAY

public static final Class<?>[] EMPTY_CLASS_ARRAY

EMPTY_OBJECT_ARRAY

public static final Object[] EMPTY_OBJECT_ARRAY

EMPTY_SERIALIZABLE_ARRAY

public static final Serializable[] EMPTY_SERIALIZABLE_ARRAY

EMPTY_STRING_ARRAY

public static final String[] EMPTY_STRING_ARRAY

Method Detail

equals

public static boolean equals(byte[] b1,
                             byte[] b2,
                             int off,
                             int len)

Checks if the subrange of two byte arrays is equal.

equals

public static boolean equals(byte[] b1,
                             int off1,
                             byte[] b2,
                             int off2,
                             int len)

Checks if the subrange of two byte arrays is equal.

allEquals

public static boolean allEquals(byte[] b,
                                int off,
                                int len,
                                byte value)

Checks if all the values in the provided range are equal to value.

compare

public static int compare(byte[] ba1,
                          byte[] ba2)

Compares two byte[]. Shorter byte[] are ordered before longer when the shorter is a prefix of the longer. The comparison considers each byte as a value from 0-255.

merge

public static <V> V[] merge(Class<V> clazz,
                            Collection<? extends Collection<? extends V>> collections,
                            Comparator<? super V> comparator)

Merges multiple already-sorted collections into one big array. Worst-case Complexity: 0 collections: constant 1 collection: O(n), where n is the number of elements in the collection 2 collection: O(n+m), where n is the number of elements in one collection, and m is the number of elements in the other collection 3+ collections: O(n*log(m)), where n is the total number of elements in all collections, and m is the number of collections

Returns:

Object[] of results.

asUnmodifiableSet

public static <E> Set<E> asUnmodifiableSet(E... array)

Gets an unmodifiable set view with the contents of a backing array.

Contains is implemented sequentially and is thus O(n). As a result, this is best used for very small sets.

In order to have correct set semantics, the array must have unique values as determined by the element equals methods. This is not checked, however, and passing in an array with duplicate values will result in duplicate values on iteration and a size that doesn't match the number of unique values.

indexOf

public static <E> int indexOf(E[] array,
                              E element)

Finds the first index of an element or -1 if not found.

indexOf

public static <E> int indexOf(E[] array,
                              E element,
                              int fromIndex)

Finds the first index of an element or -1 if not found.

lastIndexOf

public static <E> int lastIndexOf(E[] array,
                                  E element)

Finds the last index of an element or -1 if not found.

lastIndexOf

public static <E> int lastIndexOf(E[] array,
                                  E element,
                                  int fromIndex)

Finds the last index of an element or -1 if not found.

indexOf

public static <E extends Enum<E>> int indexOf(E[] array,
                                              E element)

Finds the first index of an element or -1 if not found.

indexOf

public static <E extends Enum<E>> int indexOf(E[] array,
                                              E element,
                                              int fromIndex)

Finds the first index of an element or -1 if not found.

lastIndexOf

public static <E extends Enum<E>> int lastIndexOf(E[] array,
                                                  E element)

Finds the last index of an element or -1 if not found.

lastIndexOf

public static <E extends Enum<E>> int lastIndexOf(E[] array,
                                                  E element,
                                                  int fromIndex)

Finds the last index of an element or -1 if not found.

indexOf

public static int indexOf(byte[] array,
                          byte element)

Finds the first index of an element or -1 if not found.

indexOf

public static int indexOf(byte[] array,
                          byte element,
                          int fromIndex)

Finds the first index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(byte[] array,
                              byte element)

Finds the last index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(byte[] array,
                              byte element,
                              int fromIndex)

Finds the last index of an element or -1 if not found.

indexOf

public static int indexOf(short[] array,
                          short element)

Finds the first index of an element or -1 if not found.

indexOf

public static int indexOf(short[] array,
                          short element,
                          int fromIndex)

Finds the first index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(short[] array,
                              short element)

Finds the last index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(short[] array,
                              short element,
                              int fromIndex)

Finds the last index of an element or -1 if not found.

indexOf

public static int indexOf(int[] array,
                          int element)

Finds the first index of an element or -1 if not found.

indexOf

public static int indexOf(int[] array,
                          int element,
                          int fromIndex)

Finds the first index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(int[] array,
                              int element)

Finds the last index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(int[] array,
                              int element,
                              int fromIndex)

Finds the last index of an element or -1 if not found.

indexOf

public static int indexOf(long[] array,
                          long element)

Finds the first index of an element or -1 if not found.

indexOf

public static int indexOf(long[] array,
                          long element,
                          int fromIndex)

Finds the first index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(long[] array,
                              long element)

Finds the last index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(long[] array,
                              long element,
                              int fromIndex)

Finds the last index of an element or -1 if not found.

indexOf

public static int indexOf(float[] array,
                          float element)

Finds the first index of an element or -1 if not found.

indexOf

public static int indexOf(float[] array,
                          float element,
                          int fromIndex)

Finds the first index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(float[] array,
                              float element)

Finds the last index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(float[] array,
                              float element,
                              int fromIndex)

Finds the last index of an element or -1 if not found.

indexOf

public static int indexOf(double[] array,
                          double element)

Finds the first index of an element or -1 if not found.

indexOf

public static int indexOf(double[] array,
                          double element,
                          int fromIndex)

Finds the first index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(double[] array,
                              double element)

Finds the last index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(double[] array,
                              double element,
                              int fromIndex)

Finds the last index of an element or -1 if not found.

indexOf

public static int indexOf(char[] array,
                          char element)

Finds the first index of an element or -1 if not found.

indexOf

public static int indexOf(char[] array,
                          char element,
                          int fromIndex)

Finds the first index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(char[] array,
                              char element)

Finds the last index of an element or -1 if not found.

lastIndexOf

public static int lastIndexOf(char[] array,
                              char element,
                              int fromIndex)

Finds the last index of an element or -1 if not found.

hashCode

public static int hashCode(byte[] a,
                           int off,
                           int len)

Computes hashCode compatible with Arrays.hashCode, but only across the given subset of the array.

See Also:

Arrays.hashCode(byte[])