Restrictions on the use of Fields during Initialization

[Hemant Agarwal]

compile-time error results from the test program:

 class Test {
int i = j;// compile-time error: incorrect forward reference
int j = 1;
} 

whereas the following example compiles without error:

 class Test {
Test() { k = 2; }
int j = 1;
int i = j;
int k;
} 

Why is it so?

[Stuart Ash]

Because methods, including constructors, are "after" fields: they are considered separately from the field declarations.
But between two fields, order matters.

[Adam Richards]

To put it another way: Your first assignment refers to variable j, which hasn't been declared yet, so the compiler doesn't recognize it (j).