java.lang.reflect
Class Array

java.lang.Object
  java.lang.reflect.Array

public final class Array
extends Object

This class provides methods to dynamically create and access arrays.

Method Summary

static Object	get(Object array, int index) Return the element of the array at the specified index.
static boolean	getBoolean(Object array, int index) Return the element of the array at the specified index, converted to a boolean if possible.
static byte	getByte(Object array, int index) Return the element of the array at the specified index, converted to a byte if possible.
static char	getChar(Object array, int index) Return the element of the array at the specified index, converted to a char if possible.
static double	getDouble(Object array, int index) Return the element of the array at the specified index, converted to a double if possible.
static float	getFloat(Object array, int index) Return the element of the array at the specified index, converted to a float if possible.
static int	getInt(Object array, int index) Return the element of the array at the specified index, converted to an int if possible.
static int	getLength(Object array) Return the length of the array.
static long	getLong(Object array, int index) Return the element of the array at the specified index, converted to a long if possible.
static short	getShort(Object array, int index) Return the element of the array at the specified index, converted to a short if possible.
static Object	newInstance(Class<?> componentType, int size) Return a new array of the specified component type and length.
static Object	newInstance(Class<?> componentType, int[] dimensions) Return a new multidimensional array of the specified component type and dimensions.
static void	set(Object array, int index, Object value) Set the element of the array at the specified index to the value.
static void	setBoolean(Object array, int index, boolean value) Set the element of the array at the specified index to the boolean value.
static void	setByte(Object array, int index, byte value) Set the element of the array at the specified index to the byte value.
static void	setChar(Object array, int index, char value) Set the element of the array at the specified index to the char value.
static void	setDouble(Object array, int index, double value) Set the element of the array at the specified index to the double value.
static void	setFloat(Object array, int index, float value) Set the element of the array at the specified index to the float value.
static void	setInt(Object array, int index, int value) Set the element of the array at the specified index to the int value.
static void	setLong(Object array, int index, long value) Set the element of the array at the specified index to the long value.
static void	setShort(Object array, int index, short value) Set the element of the array at the specified index to the short value.

Methods inherited from class java.lang.Object

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

Method Detail

get

public static Object get(Object array,
                         int index)
                  throws IllegalArgumentException,
                         ArrayIndexOutOfBoundsException

Return the element of the array at the specified index. This reproduces the effect of array[index] If the array component is a base type, the result is automatically wrapped.

Parameters:

array - the array

index - the index

Returns:

the requested element, possibly wrapped

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

getBoolean

public static boolean getBoolean(Object array,
                                 int index)
                          throws IllegalArgumentException,
                                 ArrayIndexOutOfBoundsException

Return the element of the array at the specified index, converted to a boolean if possible. This reproduces the effect of array[index]

Parameters:

array - the array

index - the index

Returns:

the requested element

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the element cannot be converted to the requested type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

getByte

public static byte getByte(Object array,
                           int index)
                    throws IllegalArgumentException,
                           ArrayIndexOutOfBoundsException

Return the element of the array at the specified index, converted to a byte if possible. This reproduces the effect of array[index]

Parameters:

array - the array

index - the index

Returns:

the requested element

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the element cannot be converted to the requested type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

getChar

public static char getChar(Object array,
                           int index)
                    throws IllegalArgumentException,
                           ArrayIndexOutOfBoundsException

Return the element of the array at the specified index, converted to a char if possible. This reproduces the effect of array[index]

Parameters:

array - the array

index - the index

Returns:

the requested element

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the element cannot be converted to the requested type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

getDouble

public static double getDouble(Object array,
                               int index)
                        throws IllegalArgumentException,
                               ArrayIndexOutOfBoundsException

Return the element of the array at the specified index, converted to a double if possible. This reproduces the effect of array[index]

Parameters:

array - the array

index - the index

Returns:

the requested element

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the element cannot be converted to the requested type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

getFloat

public static float getFloat(Object array,
                             int index)
                      throws IllegalArgumentException,
                             ArrayIndexOutOfBoundsException

Return the element of the array at the specified index, converted to a float if possible. This reproduces the effect of array[index]

Parameters:

array - the array

index - the index

Returns:

the requested element

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the element cannot be converted to the requested type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

getInt

public static int getInt(Object array,
                         int index)
                  throws IllegalArgumentException,
                         ArrayIndexOutOfBoundsException

Return the element of the array at the specified index, converted to an int if possible. This reproduces the effect of array[index]

Parameters:

array - the array

index - the index

Returns:

the requested element

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the element cannot be converted to the requested type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

getLength

public static int getLength(Object array)

Return the length of the array. This reproduces the effect of array.length

Parameters:

array - the array

Returns:

the length

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array

getLong

public static long getLong(Object array,
                           int index)
                    throws IllegalArgumentException,
                           ArrayIndexOutOfBoundsException

Return the element of the array at the specified index, converted to a long if possible. This reproduces the effect of array[index]

Parameters:

array - the array

index - the index

Returns:

the requested element

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the element cannot be converted to the requested type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

getShort

public static short getShort(Object array,
                             int index)
                      throws IllegalArgumentException,
                             ArrayIndexOutOfBoundsException

Return the element of the array at the specified index, converted to a short if possible. This reproduces the effect of array[index]

Parameters:

array - the array

index - the index

Returns:

the requested element

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the element cannot be converted to the requested type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

newInstance

public static Object newInstance(Class<?> componentType,
                                 int[] dimensions)
                          throws NegativeArraySizeException,
                                 IllegalArgumentException

Return a new multidimensional array of the specified component type and dimensions. This reproduces the effect of new componentType[d0][d1]...[dn] for a dimensions array of { d0, d1, ... , dn }

Parameters:

componentType - the component type of the new array

dimensions - the dimensions of the new array

Returns:

the new array

Throws:

NullPointerException - if the component type is null

NegativeArraySizeException - if any of the dimensions are negative

IllegalArgumentException - if the array of dimensions is of size zero, or exceeds the limit of the number of dimension for an array (currently 255)

newInstance

public static Object newInstance(Class<?> componentType,
                                 int size)
                          throws NegativeArraySizeException

Return a new array of the specified component type and length. This reproduces the effect of new componentType[size]

Parameters:

componentType - the component type of the new array

size - the length of the new array

Returns:

the new array

Throws:

NullPointerException - if the component type is null

NegativeArraySizeException - if the size if negative

set

public static void set(Object array,
                       int index,
                       Object value)
                throws IllegalArgumentException,
                       ArrayIndexOutOfBoundsException

Set the element of the array at the specified index to the value. This reproduces the effect of array[index] = value If the array component is a base type, the value is automatically unwrapped

Parameters:

array - the array

index - the index

value - the new value

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the value cannot be converted to the array type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

setBoolean

public static void setBoolean(Object array,
                              int index,
                              boolean value)

Set the element of the array at the specified index to the boolean value. This reproduces the effect of array[index] = value

Parameters:

array - the array

index - the index

value - the new value

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the value cannot be converted to the array type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

setByte

public static void setByte(Object array,
                           int index,
                           byte value)
                    throws IllegalArgumentException,
                           ArrayIndexOutOfBoundsException

Set the element of the array at the specified index to the byte value. This reproduces the effect of array[index] = value

Parameters:

array - the array

index - the index

value - the new value

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the value cannot be converted to the array type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

setChar

public static void setChar(Object array,
                           int index,
                           char value)
                    throws IllegalArgumentException,
                           ArrayIndexOutOfBoundsException

Set the element of the array at the specified index to the char value. This reproduces the effect of array[index] = value

Parameters:

array - the array

index - the index

value - the new value

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the value cannot be converted to the array type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

setDouble

public static void setDouble(Object array,
                             int index,
                             double value)
                      throws IllegalArgumentException,
                             ArrayIndexOutOfBoundsException

Set the element of the array at the specified index to the double value. This reproduces the effect of array[index] = value

Parameters:

array - the array

index - the index

value - the new value

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the value cannot be converted to the array type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

setFloat

public static void setFloat(Object array,
                            int index,
                            float value)
                     throws IllegalArgumentException,
                            ArrayIndexOutOfBoundsException

Set the element of the array at the specified index to the float value. This reproduces the effect of array[index] = value

Parameters:

array - the array

index - the index

value - the new value

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the value cannot be converted to the array type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

setInt

public static void setInt(Object array,
                          int index,
                          int value)
                   throws IllegalArgumentException,
                          ArrayIndexOutOfBoundsException

Set the element of the array at the specified index to the int value. This reproduces the effect of array[index] = value

Parameters:

array - the array

index - the index

value - the new value

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the value cannot be converted to the array type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

setLong

public static void setLong(Object array,
                           int index,
                           long value)
                    throws IllegalArgumentException,
                           ArrayIndexOutOfBoundsException

Set the element of the array at the specified index to the long value. This reproduces the effect of array[index] = value

Parameters:

array - the array

index - the index

value - the new value

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the value cannot be converted to the array type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length

setShort

public static void setShort(Object array,
                            int index,
                            short value)
                     throws IllegalArgumentException,
                            ArrayIndexOutOfBoundsException

Set the element of the array at the specified index to the short value. This reproduces the effect of array[index] = value

Parameters:

array - the array

index - the index

value - the new value

Throws:

NullPointerException - if the array is null

IllegalArgumentException - if the array is not an array or the value cannot be converted to the array type by a widening conversion

ArrayIndexOutOfBoundsException - if the index is out of bounds -- negative or greater than or equal to the array length