Java Module java.base Package java.lang.reflect Class Array（JDK11）

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

```
public final class Array
extends Object
```
The Array class provides static methods to dynamically create and access Java arrays.
Array permits widening conversions to occur during a get or set operation, but throws an IllegalArgumentException if a narrowing conversion would occur.
Since:
1.1

Method Summary

All Methods Static Methods Concrete 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 Detail
  - 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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Java Module java.base Package java.lang.reflect Class Array（JDK11）

Class Array

Method Summary

Methods declared in class java.lang.Object

Method Detail

newInstance

newInstance

getLength

get

getBoolean

getByte

getChar

getShort

getInt

getLong

getFloat

getDouble

set

setBoolean

setByte

setChar

setShort

setInt

setLong

setFloat

setDouble