public final class Array extends Object
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.
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. |
public static Object newInstance(Class<?> componentType, int length) throws NegativeArraySizeException
int[] x = {length}; Array.newInstance(componentType, x);
The number of dimensions of the new array must not exceed 255.
componentType
- the Class
object representing the
component type of the new arraylength
- the length of the new arrayNullPointerException
- if the specified
componentType
parameter is nullIllegalArgumentException
- if componentType is Void.TYPE
or if the number of dimensions of the requested array
instance exceed 255.NegativeArraySizeException
- if the specified length
is negativepublic static Object newInstance(Class<?> componentType, int... dimensions) throws IllegalArgumentException, NegativeArraySizeException
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.
componentType
- the Class
object representing the component
type of the new arraydimensions
- an array of int
representing the dimensions of
the new arrayNullPointerException
- if the specified
componentType
argument is nullIllegalArgumentException
- 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.public static int getLength(Object array) throws IllegalArgumentException
int
.array
- the arrayIllegalArgumentException
- if the object argument is not
an arraypublic static Object get(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
array
- the arrayindex
- the indexNullPointerException
- If the specified object is nullIllegalArgumentException
- If the specified object is not
an arrayArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to the
length of the specified arraypublic static boolean getBoolean(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
boolean
.array
- the arrayindex
- the indexNullPointerException
- If the specified object is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to the
length of the specified arrayget(java.lang.Object, int)
public static byte getByte(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
byte
.array
- the arrayindex
- the indexNullPointerException
- If the specified object is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to the
length of the specified arrayget(java.lang.Object, int)
public static char getChar(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
char
.array
- the arrayindex
- the indexNullPointerException
- If the specified object is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to the
length of the specified arrayget(java.lang.Object, int)
public static short getShort(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
short
.array
- the arrayindex
- the indexNullPointerException
- If the specified object is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to the
length of the specified arrayget(java.lang.Object, int)
public static int getInt(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
int
.array
- the arrayindex
- the indexNullPointerException
- If the specified object is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to the
length of the specified arrayget(java.lang.Object, int)
public static long getLong(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
long
.array
- the arrayindex
- the indexNullPointerException
- If the specified object is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to the
length of the specified arrayget(java.lang.Object, int)
public static float getFloat(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
float
.array
- the arrayindex
- the indexNullPointerException
- If the specified object is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to the
length of the specified arrayget(java.lang.Object, int)
public static double getDouble(Object array, int index) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
double
.array
- the arrayindex
- the indexNullPointerException
- If the specified object is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to the
length of the specified arrayget(java.lang.Object, int)
public static void set(Object array, int index, Object value) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
array
- the arrayindex
- the index into the arrayvalue
- the new value of the indexed componentNullPointerException
- If the specified object argument
is nullIllegalArgumentException
- If the specified object argument
is not an array, or if the array component type is primitive and
an unwrapping conversion failsArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to
the length of the specified arraypublic static void setBoolean(Object array, int index, boolean z) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
boolean
value.array
- the arrayindex
- the index into the arrayz
- the new value of the indexed componentNullPointerException
- If the specified object argument
is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to
the length of the specified arrayset(java.lang.Object, int, java.lang.Object)
public static void setByte(Object array, int index, byte b) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
byte
value.array
- the arrayindex
- the index into the arrayb
- the new value of the indexed componentNullPointerException
- If the specified object argument
is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to
the length of the specified arrayset(java.lang.Object, int, java.lang.Object)
public static void setChar(Object array, int index, char c) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
char
value.array
- the arrayindex
- the index into the arrayc
- the new value of the indexed componentNullPointerException
- If the specified object argument
is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to
the length of the specified arrayset(java.lang.Object, int, java.lang.Object)
public static void setShort(Object array, int index, short s) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
short
value.array
- the arrayindex
- the index into the arrays
- the new value of the indexed componentNullPointerException
- If the specified object argument
is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to
the length of the specified arrayset(java.lang.Object, int, java.lang.Object)
public static void setInt(Object array, int index, int i) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
int
value.array
- the arrayindex
- the index into the arrayi
- the new value of the indexed componentNullPointerException
- If the specified object argument
is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to
the length of the specified arrayset(java.lang.Object, int, java.lang.Object)
public static void setLong(Object array, int index, long l) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
long
value.array
- the arrayindex
- the index into the arrayl
- the new value of the indexed componentNullPointerException
- If the specified object argument
is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to
the length of the specified arrayset(java.lang.Object, int, java.lang.Object)
public static void setFloat(Object array, int index, float f) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
float
value.array
- the arrayindex
- the index into the arrayf
- the new value of the indexed componentNullPointerException
- If the specified object argument
is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to
the length of the specified arrayset(java.lang.Object, int, java.lang.Object)
public static void setDouble(Object array, int index, double d) throws IllegalArgumentException, ArrayIndexOutOfBoundsException
double
value.array
- the arrayindex
- the index into the arrayd
- the new value of the indexed componentNullPointerException
- If the specified object argument
is nullIllegalArgumentException
- 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 conversionArrayIndexOutOfBoundsException
- If the specified index
argument is negative, or if it is greater than or equal to
the length of the specified arrayset(java.lang.Object, int, java.lang.Object)
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