EXPRESSIONS

Field Access Expressions

15.10

15.9.3   Example: Array Creation and Out of Memory Detection

If evaluation of an array creation expression finds there is insufficient memory to

perform the creation operation, then an

OutOfMemoryError

 is thrown. This check

occurs only after evaluation of all dimension expressions has completed normally.

So, for example, the test program:

class Test {

public static void main(String[] args) {

int len = 0, oldlen = 0;

Object[] a = new Object[0];

try {

for (;;) {

++len;

Object[] temp = new Object[oldlen = len];

temp[0] = a;

a = temp;

}

} catch (Error e) {

System.out.println(e + ", " + (oldlen==len));

}

}

}

prints:

java.lang.OutOfMemoryError, true

because the out of memory condition is detected after the argument expression

oldlen

 =

len

 is evaluated.

Compare this to class instance creation expressions ( 15.8), which detect the

out of memory condition before evaluating argument expressions ( 15.8.2).

15.10   Field Access Expressions

A field access expression may access a field of an object or array, a reference to

which is the value of either an expression or the special keyword

super

. (It is also

possible to refer to a field of the current instance or current class by using a simple

name; see  15.13.1.)

FieldAccess:

Primary

 .

Identifier

super .

Identifier

The meaning of a field access expression is determined using the same rules

as for qualified names ( 6.6), but limited by the fact that an expression cannot

denote a package, class type, or interface type.

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