Class Array

public final class Array
extends Object

Since:

1.1

• Method Summary

  All MethodsStatic MethodsConcrete Methods

  Modifier and Type	Method	Description
  static Object	get​(Object array, int index)	Returns the value of the indexed component in the specified array object.
  static boolean	getBoolean​(Object array, int index)	Returns the value of the indexed component in the specified array object, as a boolean.
  static byte	getByte​(Object array, int index)	Returns the value of the indexed component in the specified array object, as a byte.
  static char	getChar​(Object array, int index)	Returns the value of the indexed component in the specified array object, as a char.
  static double	getDouble​(Object array, int index)	Returns the value of the indexed component in the specified array object, as a double.
  static float	getFloat​(Object array, int index)	Returns the value of the indexed component in the specified array object, as a float.
  static int	getInt​(Object array, int index)	Returns the value of the indexed component in the specified array object, as an int.
  static int	getLength​(Object array)	Returns the length of the specified array object, as an int.
  static long	getLong​(Object array, int index)	Returns the value of the indexed component in the specified array object, as a long.
  static short	getShort​(Object array, int index)	Returns the value of the indexed component in the specified array object, as a short.
  static Object	newInstance​(Class<?> componentType, int length)	Creates a new array with the specified component type and length.
  static Object	newInstance​(Class<?> componentType, int... dimensions)	Creates a new array with the specified component type and dimensions.
  static void	set​(Object array, int index, Object value)	Sets the value of the indexed component of the specified array object to the specified new value.
  static void	setBoolean​(Object array, int index, boolean z)	Sets the value of the indexed component of the specified array object to the specified boolean value.
  static void	setByte​(Object array, int index, byte b)	Sets the value of the indexed component of the specified array object to the specified byte value.
  static void	setChar​(Object array, int index, char c)	Sets the value of the indexed component of the specified array object to the specified char value.
  static void	setDouble​(Object array, int index, double d)	Sets the value of the indexed component of the specified array object to the specified double value.
  static void	setFloat​(Object array, int index, float f)	Sets the value of the indexed component of the specified array object to the specified float value.
  static void	setInt​(Object array, int index, int i)	Sets the value of the indexed component of the specified array object to the specified int value.
  static void	setLong​(Object array, int index, long l)	Sets the value of the indexed component of the specified array object to the specified long value.
  static void	setShort​(Object array, int index, short s)	Sets the value of the indexed component of the specified array object to the specified short value.

  Methods declared in class java.lang.Object

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

• Method Details

  • newInstance

    public static Object newInstance​(Class<?> componentType, int length) throws NegativeArraySizeException
    Creates a new array with the specified component type and length. Invoking this method is equivalent to creating an array as follows:

     int[] x = {length};
     Array.newInstance(componentType, x);
     

    The number of dimensions of the new array must not exceed 255.

    Parameters:

    componentType - the Class object representing the component type of the new array

    length - the length of the new array

    Returns:

    the new array

    Throws:

    NullPointerException - if the specified componentType parameter is null

    IllegalArgumentException - if componentType is Void.TYPE or if the number of dimensions of the requested array instance exceed 255.

    NegativeArraySizeException - if the specified length is negative

  • newInstance

    public static Object newInstance​(Class<?> componentType, int... dimensions) throws IllegalArgumentException, NegativeArraySizeException
    Creates a new array with the specified component type and dimensions. If componentType represents a non-array class or interface, the new array has dimensions.length dimensions and componentType as its component type. If componentType represents an array class, the number of dimensions of the new array is equal to the sum of dimensions.length and the number of dimensions of componentType. In this case, the component type of the new array is the component type of componentType.

    The number of dimensions of the new array must not exceed 255.

    Parameters:

    componentType - the Class object representing the component type of the new array

    dimensions - an array of int representing the dimensions of the new array

    Returns:

    the new array

    Throws:

    NullPointerException - if the specified componentType argument is null

    IllegalArgumentException - if the specified dimensions argument is a zero-dimensional array, if componentType is Void.TYPE, or if the number of dimensions of the requested array instance exceed 255.

    NegativeArraySizeException - if any of the components in the specified dimensions argument is negative.

  • getLength

    public static int getLength​(Object array) throws IllegalArgumentException
    Returns the length of the specified array object, as an int.

    Parameters:

    array - the array

    Returns:

    the length of the array

    Throws:

    IllegalArgumentException - if the object argument is not an array

  • get

    public static Object get​(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Returns the value of the indexed component in the specified array object. The value is automatically wrapped in an object if it has a primitive type.

    Parameters:

    array - the array

    index - the index

    Returns:

    the (possibly wrapped) value of the indexed component in the specified array

    Throws:

    NullPointerException - If the specified object is null

    IllegalArgumentException - If the specified object is not an array

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

  • getBoolean

    public static boolean getBoolean​(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Returns the value of the indexed component in the specified array object, as a boolean.

    Parameters:

    array - the array

    index - the index

    Returns:

    the value of the indexed component in the specified array

    Throws:

    NullPointerException - If the specified object is null

    IllegalArgumentException - If the specified object is not an array, or if the indexed element cannot be converted to the return type by an identity or widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    get(java.lang.Object, int)

  • getByte

    public static byte getByte​(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Returns the value of the indexed component in the specified array object, as a byte.

    Parameters:

    array - the array

    index - the index

    Returns:

    the value of the indexed component in the specified array

    Throws:

    NullPointerException - If the specified object is null

    IllegalArgumentException - If the specified object is not an array, or if the indexed element cannot be converted to the return type by an identity or widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    get(java.lang.Object, int)

  • getChar

    public static char getChar​(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Returns the value of the indexed component in the specified array object, as a char.

    Parameters:

    array - the array

    index - the index

    Returns:

    the value of the indexed component in the specified array

    Throws:

    NullPointerException - If the specified object is null

    IllegalArgumentException - If the specified object is not an array, or if the indexed element cannot be converted to the return type by an identity or widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    get(java.lang.Object, int)

  • getShort

    public static short getShort​(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Returns the value of the indexed component in the specified array object, as a short.

    Parameters:

    array - the array

    index - the index

    Returns:

    the value of the indexed component in the specified array

    Throws:

    NullPointerException - If the specified object is null

    IllegalArgumentException - If the specified object is not an array, or if the indexed element cannot be converted to the return type by an identity or widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    get(java.lang.Object, int)

  • getInt

    public static int getInt​(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Returns the value of the indexed component in the specified array object, as an int.

    Parameters:

    array - the array

    index - the index

    Returns:

    the value of the indexed component in the specified array

    Throws:

    NullPointerException - If the specified object is null

    IllegalArgumentException - If the specified object is not an array, or if the indexed element cannot be converted to the return type by an identity or widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    get(java.lang.Object, int)

  • getLong

    public static long getLong​(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Returns the value of the indexed component in the specified array object, as a long.

    Parameters:

    array - the array

    index - the index

    Returns:

    the value of the indexed component in the specified array

    Throws:

    NullPointerException - If the specified object is null

    IllegalArgumentException - If the specified object is not an array, or if the indexed element cannot be converted to the return type by an identity or widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    get(java.lang.Object, int)

  • getFloat

    public static float getFloat​(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Returns the value of the indexed component in the specified array object, as a float.

    Parameters:

    array - the array

    index - the index

    Returns:

    the value of the indexed component in the specified array

    Throws:

    NullPointerException - If the specified object is null

    IllegalArgumentException - If the specified object is not an array, or if the indexed element cannot be converted to the return type by an identity or widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    get(java.lang.Object, int)

  • getDouble

    public static double getDouble​(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Returns the value of the indexed component in the specified array object, as a double.

    Parameters:

    array - the array

    index - the index

    Returns:

    the value of the indexed component in the specified array

    Throws:

    NullPointerException - If the specified object is null

    IllegalArgumentException - If the specified object is not an array, or if the indexed element cannot be converted to the return type by an identity or widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    get(java.lang.Object, int)

  • set

    public static void set​(Object array, int index, Object value) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Sets the value of the indexed component of the specified array object to the specified new value. The new value is first automatically unwrapped if the array has a primitive component type.

    Parameters:

    array - the array

    index - the index into the array

    value - the new value of the indexed component

    Throws:

    NullPointerException - If the specified object argument is null

    IllegalArgumentException - If the specified object argument is not an array, or if the array component type is primitive and an unwrapping conversion fails

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

  • setBoolean

    public static void setBoolean​(Object array, int index, boolean z) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Sets the value of the indexed component of the specified array object to the specified boolean value.

    Parameters:

    array - the array

    index - the index into the array

    z - the new value of the indexed component

    Throws:

    NullPointerException - If the specified object argument is null

    IllegalArgumentException - If the specified object argument is not an array, or if the specified value cannot be converted to the underlying array's component type by an identity or a primitive widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    set(java.lang.Object, int, java.lang.Object)

  • setByte

    public static void setByte​(Object array, int index, byte b) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Sets the value of the indexed component of the specified array object to the specified byte value.

    Parameters:

    array - the array

    index - the index into the array

    b - the new value of the indexed component

    Throws:

    NullPointerException - If the specified object argument is null

    IllegalArgumentException - If the specified object argument is not an array, or if the specified value cannot be converted to the underlying array's component type by an identity or a primitive widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    set(java.lang.Object, int, java.lang.Object)

  • setChar

    public static void setChar​(Object array, int index, char c) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Sets the value of the indexed component of the specified array object to the specified char value.

    Parameters:

    array - the array

    index - the index into the array

    c - the new value of the indexed component

    Throws:

    NullPointerException - If the specified object argument is null

    IllegalArgumentException - If the specified object argument is not an array, or if the specified value cannot be converted to the underlying array's component type by an identity or a primitive widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    set(java.lang.Object, int, java.lang.Object)

  • setShort

    public static void setShort​(Object array, int index, short s) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Sets the value of the indexed component of the specified array object to the specified short value.

    Parameters:

    array - the array

    index - the index into the array

    s - the new value of the indexed component

    Throws:

    NullPointerException - If the specified object argument is null

    IllegalArgumentException - If the specified object argument is not an array, or if the specified value cannot be converted to the underlying array's component type by an identity or a primitive widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    set(java.lang.Object, int, java.lang.Object)

  • setInt

    public static void setInt​(Object array, int index, int i) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Sets the value of the indexed component of the specified array object to the specified int value.

    Parameters:

    array - the array

    index - the index into the array

    i - the new value of the indexed component

    Throws:

    NullPointerException - If the specified object argument is null

    IllegalArgumentException - If the specified object argument is not an array, or if the specified value cannot be converted to the underlying array's component type by an identity or a primitive widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    set(java.lang.Object, int, java.lang.Object)

  • setLong

    public static void setLong​(Object array, int index, long l) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Sets the value of the indexed component of the specified array object to the specified long value.

    Parameters:

    array - the array

    index - the index into the array

    l - the new value of the indexed component

    Throws:

    NullPointerException - If the specified object argument is null

    IllegalArgumentException - If the specified object argument is not an array, or if the specified value cannot be converted to the underlying array's component type by an identity or a primitive widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    set(java.lang.Object, int, java.lang.Object)

  • setFloat

    public static void setFloat​(Object array, int index, float f) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Sets the value of the indexed component of the specified array object to the specified float value.

    Parameters:

    array - the array

    index - the index into the array

    f - the new value of the indexed component

    Throws:

    NullPointerException - If the specified object argument is null

    IllegalArgumentException - If the specified object argument is not an array, or if the specified value cannot be converted to the underlying array's component type by an identity or a primitive widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    set(java.lang.Object, int, java.lang.Object)

  • setDouble

    public static void setDouble​(Object array, int index, double d) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
    Sets the value of the indexed component of the specified array object to the specified double value.

    Parameters:

    array - the array

    index - the index into the array

    d - the new value of the indexed component

    Throws:

    NullPointerException - If the specified object argument is null

    IllegalArgumentException - If the specified object argument is not an array, or if the specified value cannot be converted to the underlying array's component type by an identity or a primitive widening conversion

    ArrayIndexOutOfBoundsException - If the specified index argument is negative, or if it is greater than or equal to the length of the specified array

    See Also:

    set(java.lang.Object, int, java.lang.Object)

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