ArraysExt (TestHelpers 1.0-SNAPSHOT API)

java.lang.Object
- eu.simuline.util.ArraysExt<E>

Type Parameters:

E - The type of the entry of the array under consideration.
```
public final class ArraysExt<E>
extends Object
```
An add on to the class Arrays. Partially this is influenced by Collections.

Version:

1.0

Author:

Ernst Reissner

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`(package private) static class`	`ArraysExt.ArrayComparator<O>` Comparator class which implements a kind of lexical ordering on arrays based on the ordering of the components defined by `atomic`.

Field Summary

Fields
Modifier and Type Field and Description

static Object[] EMPTY
The class double[][].

Fields
Modifier and Type	Field and Description
`static Object[]`	`EMPTY` The class `double[][]`.

Constructor Summary

Constructors
Modifier Constructor and Description

private ArraysExt()

Constructors
Modifier	Constructor and Description
`private`	`ArraysExt()`

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`private static Object`	`createUnWrappedEmptyArray(Object[] wrappedArray)` Returns an empty array with type like `wrappedArray` with basic type replaced by its wrapper.
`private static Object[]`	`createWrappedEmptyArray(Object elemArray)` Returns an empty array with type like `elemArray` with basic type replaced by its wrapper.
`static void`	`fill(Object[] array, Object obj)` Replaces all of the elements of the specified array with the specified element.
`static Comparator<Object[]>`	`getComparator(Comparator<Object> atomic)` Returns a comparator of the class `ArraysExt.ArrayComparator` which implements a kind of lexical ordering on arrays based on the ordering of the components defined by `atomic`.
`static Object[]`	`nCopies(int num, Object obj)` Returns an array consisting of `n` copies of the specified object.
`static List<Object>`	`recAsList(Object[] array)` Turns the given array recursively into a hierarchy of nested lists.
`static Object`	`recAsList(Object source, Class<?> cls)` Converts `source` which is typically an array, recursively into an nested `List` with the given atomic entry type using the specified caster.
`static Object`	`recAsList(Object source, Class<?> cls, Caster caster)` Converts `source` which is typically an array, recursively into an nested `List` with the given atomic entry type using the specified caster.
`static void`	`reverse(Object[] array)` Reverses the order of the elements in the specified array.
`static boolean[]`	`toPrimitive(Boolean[] arr)` Converts an array of `Boolean`s into an array of according `boolean`s.
`static byte[]`	`toPrimitive(Byte[] arr)` Converts an array of `Byte`s into an array of according `byte`s.
`static char[]`	`toPrimitive(Character[] arr)` Converts an array of `Character`s into an array of according `char`s.
`static double[]`	`toPrimitive(Double[] arr)` Converts an array of `Double`s into an array of according `double`s.
`static float[]`	`toPrimitive(Float[] arr)` Converts an array of `Float`s into an array of according `float`s.
`static int[]`	`toPrimitive(Integer[] arr)` Converts an array of `Integer`s into an array of according `int`s.
`static long[]`	`toPrimitive(Long[] arr)` Converts an array of `Long`s into an array of according `long`s.
`static short[]`	`toPrimitive(Short[] arr)` Converts an array of `Short`s into an array of according `short`s.
`static Object`	`unWrapArray(Object[] wrappedArray)` Returns an array which corresponds with the given one except that the entries are unwrapped.
`static Object[]`	`wrapArray(Object elemArray)` Returns an array which corresponds with the given one except that the entries are wrapped.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - EMPTY
```
public static final Object[] EMPTY
```
    The class double[][].
- Constructor Detail
  - ArraysExt
```
private ArraysExt()
```
- Method Detail
  - reverse
```
public static void reverse(Object[] array)
```
    Reverses the order of the elements in the specified array. This method runs in linear time.
    
    Parameters:
    
    array - the array whose elements are to be reversed.
  - fill
```
public static void fill(Object[] array,
                        Object obj)
```
    Replaces all of the elements of the specified array with the specified element. This method runs in linear time.
    
    Parameters:
    
    array - the array to be filled with the specified element.
    
    obj - The element with which to fill the specified array.
  - nCopies
```
public static Object[] nCopies(int num,
                               Object obj)
```
    Returns an array consisting of n copies of the specified object. The newly allocated data object is tiny (it contains a single reference to the data object).
    
    Parameters:
    
    num - the number of elements in the returned list.
    
    obj - the element to appear repeatedly in the returned list.
    
    Returns:
    
    an array consisting of n copies of the specified object.
    
    Throws:
    
    IllegalArgumentException - if n < 0.
  - recAsList
```
public static List<Object> recAsList(Object[] array)
```
    Turns the given array recursively into a hierarchy of nested lists. Note that unlike Arrays.asList, this is not a simple wrapper!
    
    Parameters:
    
    array - an array of objects which may in turn be arrays of objects.
    
    Returns:
    
    a list list of objects satisfying list.get(i) == array[i] if array[i] is not an Object[]; list.get(i) == recAsList(array[i]) otherwise. Note that list may be a nested list.
    
    See Also:
    
    CollectionsExt.recToArray(List)
  - recAsList
```
public static Object recAsList(Object source,
                               Class<?> cls)
```
    Converts source which is typically an array, recursively into an nested List with the given atomic entry type using the specified caster. Note that if source is not an array, it must be compatible with cls up to equivalence of basic classes and their wrappers and up to subclassing.
    Parameters:
    
    source - an arbitrary Object, but typically an array as e.g. Object[][] or double[].
    
    cls - Up to compatibility defined by caster, the type of the entries of the return value. Recursive conversion from arrays to lists stops if an entry of type compatible with cls is found.
    Note that this may also be a primitive type such as int or an array type Double[][][] or List[][][] or even int[][][].
    
    Returns:
    if cls and source are assignment compatible up to equivalence of basic classes and their wrappers, source is returned.
    if cls and source are not compatible, source must be an array; otherwise an exception is thrown.
    In the former case, a list list of objects is returned satisfying list.size() == Array.getLength(source) and list.get(i) == recAsList(Array.get(source,i),cls) for all valid indices i.
    Note that the return value is either the result of a casting process or a list. In the latter case its entries are either lists themselves or again the result of a casting and so on. Clearly its atomic entries are always Objects even when starting with sources of type int[] for instance.
    Throws:
    
    IllegalArgumentException - if source is neither an array, nor assignment compatible with cls up to equivalence between basic types and their wrappers. Also if source is an array, and this condition holds for some component. This is a recursive definition.
  - recAsList
```
public static Object recAsList(Object source,
                               Class<?> cls,
                               Caster caster)
```
    Converts source which is typically an array, recursively into an nested List with the given atomic entry type using the specified caster. Note that if source is not an array, it must be compatible with cls with respect to caster.
    Parameters:
    
    source - an arbitrary Object, but typically an array as e.g. Object[][] or double[].
    
    cls - Up to compatibility defined by caster, the type of the entries of the return value. Recursive conversion from arrays to lists stops if an entry of type compatible with cls is found.
    Note that this may also be a primitive type such as int or an array type Double[][][] or List[][][] or even int[][][].
    
    caster - performs the conversion of the top-level elements of the source.
    
    Returns:
    if cls and source are compatible (see Caster.areCompatible(java.lang.Class<?>, java.lang.Object)), the cast of source is returned.
    Note that compatibility is up to wrapping of elementary types and unwrapping of their wrappers. Arrays are converted to Lists applying this method recursively to their entries.
    if cls and source are not compatible, source must be an array; otherwise an exception is thrown.
    In the former case, a list list of objects is returned satisfying list.size() == Array.getLength(source) and list.get(i) == recAsList(Array.get(source,i),.. ,caster) for all valid indices i.
    Note that the return value is either the result of a casting process or a list. In the latter case its entries are either lists themselves or again the result of a casting and so on. Clearly its atomic entries are always Objects even when starting with sources of type int[] for instance.
    Throws:
    
    IllegalArgumentException - if source is neither an array, nor compatible with cls with respect to caster. Also if source is an array, and this condition holds for some component. This is a recursive definition.
  - createWrappedEmptyArray
```
private static Object[] createWrappedEmptyArray(Object elemArray)
```
    Returns an empty array with type like elemArray with basic type replaced by its wrapper.
    
    Parameters:
    
    elemArray - a non-null array with elementary entry type such as double[][][].
    
    Returns:
    
    an empty array with type like elemArray with basic type replaced by its wrapper. For example createWrappedEmptyArray(new int[][][] {....}) yields new Integer[][][] {}.
    
    Throws:
    
    IllegalArgumentException - if elemArray is not an array or if its entry type is not elementary as e.g. for new Integer(0) or for new Integer[][] {}.
    
    NullPointerException - if elemArray is null
  - createUnWrappedEmptyArray
```
private static Object createUnWrappedEmptyArray(Object[] wrappedArray)
```
    Returns an empty array with type like wrappedArray with basic type replaced by its wrapper.
    
    Parameters:
    
    wrappedArray - a non-null array with wrapper entry type such as Double[][][].
    
    Returns:
    
    an empty array with type like wrapperArray with basic type replaced by its wrapper. For example createUnWrappedEmptyArray(new Integer[][][] {....}) yields new int[][][] {}.
    
    Throws:
    
    IllegalArgumentException - if the entry type of wrappedArray is no wrapper type as e.g. for new int[][] {}.
  - wrapArray
```
public static Object[] wrapArray(Object elemArray)
```
    Returns an array which corresponds with the given one except that the entries are wrapped.
    
    Parameters:
    
    elemArray - an array with elementary component type as e.g. new int[][] {}. May also be null.
    
    Returns:
    
    null if elemArray == null. an array with the same length as elemArray. The type of the components is the wrapper type of the type of the components of elemArray. Also the entries are those of elemArray just wrapped.
    
    Throws:
    
    IllegalArgumentException - if elemArray is not an array or if its entry type is not elementary as e.g. for new Integer(0) or for new Integer[][] {}.
  - toPrimitive
```
public static double[] toPrimitive(Double[] arr)
```
    Converts an array of Doubles into an array of according doubles.
  - toPrimitive
```
public static float[] toPrimitive(Float[] arr)
```
    Converts an array of Floats into an array of according floats.
  - toPrimitive
```
public static long[] toPrimitive(Long[] arr)
```
    Converts an array of Longs into an array of according longs.
  - toPrimitive
```
public static int[] toPrimitive(Integer[] arr)
```
    Converts an array of Integers into an array of according ints.
  - toPrimitive
```
public static short[] toPrimitive(Short[] arr)
```
    Converts an array of Shorts into an array of according shorts.
  - toPrimitive
```
public static byte[] toPrimitive(Byte[] arr)
```
    Converts an array of Bytes into an array of according bytes.
  - toPrimitive
```
public static boolean[] toPrimitive(Boolean[] arr)
```
    Converts an array of Booleans into an array of according booleans.
  - toPrimitive
```
public static char[] toPrimitive(Character[] arr)
```
    Converts an array of Characters into an array of according chars.
  - unWrapArray
```
public static Object unWrapArray(Object[] wrappedArray)
```
    Returns an array which corresponds with the given one except that the entries are unwrapped.
    
    Parameters:
    
    wrappedArray - an array with a wrapper as component type as e.g. new Integer[][] {}. May also be null.
    
    Returns:
    
    null if wrappedArray == null. an array with the same length as wrappedArray. The type of the components is the wrapped elementary type of the type of the components of wrappedArray. Also the entries are those of wrappedArray just unwrapped.
    
    Throws:
    
    IllegalArgumentException - if the entry type of wrappedArray is no wrapper as e.g. for new int[][] {} and for new Object[][] {}.
  - getComparator
```
public static Comparator<Object[]> getComparator(Comparator<Object> atomic)
```
    Returns a comparator of the class ArraysExt.ArrayComparator which implements a kind of lexical ordering on arrays based on the ordering of the components defined by atomic.
    
    Parameters:
    
    atomic - a Comparator for the components of arrays.
    
    Returns:
    
    a Comparator for arrays.

Class ArraysExt<E>

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

EMPTY

Constructor Detail

ArraysExt

Method Detail

reverse

fill

nCopies

recAsList

recAsList

recAsList

createWrappedEmptyArray

createUnWrappedEmptyArray

wrapArray

toPrimitive

toPrimitive

toPrimitive

toPrimitive

toPrimitive

toPrimitive

toPrimitive

toPrimitive

unWrapArray

getComparator