14.3.3

Hiding of Names by Local Variables

BLOCKS AND STATEMENTS

which compiles correctly and produces the output:

2+1=3

The initializer for

three

 can correctly refer to the variable

two

 declared in an ear 

lier declarator, and the method invocation in the next line can correctly refer to the

variable

three

 declared earlier in the block.

The scope of a local variable declared in a

for

 statement is the rest of the

for

statement, including its own initializer.

If a declaration of an identifier as a local variable appears within the scope of

a parameter or local variable of the same name, a compile time error occurs. Thus

the following example does not compile:

class Test {

public static void main(String[] args) {

int i;

for (int i = 0; i < 10; i++)

System.out.println(i);

}

}

This restriction helps to detect some otherwise very obscure bugs. (A similar

restriction on hiding of members by local variables was judged impractical,

because the addition of a member in a superclass could cause subclasses to have to

rename local variables.)

On the other hand, local variables with the same name may be declared in two

separate blocks or

for

 statements neither of which contains the other. Thus:

class Test {

public static void main(String[] args) {

for (int i = 0; i < 10; i++)

System.out.print(i + " ");

for (int i = 10; i > 0; i  )

System.out.print(i + " ");

System.out.println();

}

}

compiles without error and, when executed, produces the output:

0 1 2 3 4 5 6 7 8 9 10 9 8 7 6 5 4 3 2 1

14.3.3   Hiding of Names by Local Variables

If a name declared as a local variable is already declared as a field or type name,

then that outer declaration is hidden throughout the scope of the local variable.

The field or type name can almost always ( 6.8) still be accessed using an appro 

priately qualified name. For example, the keyword

this

 can be used to access a

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