Qs about scope

[chi Lin]

Could some one advise why compiler accept 2nd time " i " declaration on prog1 but object prog2 ?
thanks
chichih
class Prog1 {
int i;
{ int i;} //compiler accept 2nd time declaration of i

public static void main (String args[]) {
int i;

}
}
==================================================================
class Prog2 {
int i;
public static void main (String args[]) {
int i;
{ int i;} // compiler object 2nd time i declarationd
}

[Michael Ernest]

A class can have anonymous scope; methods can't, unless it's part of an inner class definition. In your second example, the second initialization of i would work if the code braces were "named," i.e., preceded by an if/while statement or some other constructs that labels the ensuing scope declaration.
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Michael Ernest, co-author of: The Complete Java 2 Certification Study Guide
[This message has been edited by Michael Ernest (edited December 28, 2001).]

[Raghav Sam]

Originally posted by chichih Lin:
Could some one advise why compiler accept 2nd time " i " declaration on prog1 but object prog2 ?
thanks
chichih
class Prog1 {
int i;
{ int i;} //compiler accept 2nd time declaration of i

public static void main (String args[]) {
int i;

}
}
==================================================================
class Prog2 {
int i;
public static void main (String args[]) {
int i;
{ int i;} // compiler object 2nd time i declarationd
}

In class Prog2, just try placing the code { int i;} before int i as in:

class Prog2 {
  int i;
public static void main (String args[]) {
  { int i;} //1 - this works
  int i;    //2
}
}

This is because the scope of i in line //1 ends with the block itself and the scope of i in line //2 starts to the right of the that line and extends for the remaining block.
In your example,

class Prog2 {
int i;
public static void main (String args[]) {
int i;  //3
{ int i;} //4  compiler object 2nd time i declarationd 
}
}

the scope of i in line //3 is the entire main method including, inside the block in line //4. That is why you get an error.
------------------
Raghav.