ARRAYS

Array Store Exception

10.10

10.8

Class

 Objects for Arrays

Every array has an associated

Class

 object, shared with all other arrays with the

same component type. The superclass of an array type is considered to be

Object

,

as shown by the following example code:

class Test {

public static void main(String[] args) {

int[] ia = new int[3];

System.out.println(ia.getClass());

System.out.println(ia.getClass().getSuperclass());

}

}

which prints:

class [I

class java.lang.Object

where the string  

[I

  is the run time type signature for the class object  array

with component type

int

  ( 20.1.1).

10.9   An Array of Characters is Not a

String

In Java, unlike C, an array of

char

 is not a

String

 ( 20.12), and neither a

String

nor an array of

char

 is terminated by

 \u0000 

 (the

NUL

 character).

A Java

String

 object is immutable, that is, its contents never change, while

an array of

char

 has mutable elements. The method

toCharArray

 in class

String

 returns an array of characters containing the same character sequence as a

String

. The class

StringBuffer

 implements useful methods on mutable arrays

of characters ( 20.13).

10.10   Array Store Exception

If an array variable

v

 has type

A[]

, where

A

 is a reference type, then

v

 can hold a

reference to an instance of any array type

B[]

, provided

B

 can be assigned to

A

.

Thus, the example:

class Point { int x, y; }

class ColoredPoint extends Point { int color; }

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