Java compact1, compact2, compact3 java.lang.reflect Class Array（JDK8）

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)