Re: "static context"
On 04/20/2012 09:27 PM, Stefan Ram wrote:
ram@zedat.fu-berlin.de (Stefan Ram) writes:
java.lang.Thread . dumpStack() java.lang.System.out . print( 2 )
A ??type name?? is a special kind of context, it is a static context.
JLS 7 defines ??static context?? in 8.1.3, but the compiler
uses another meaning of ??static context??.
For example, the call ??dumpStack()?? in
class A { void m(){ java.lang.Thread.dumpStack(); }}
is /not/ in a static context according to JLS 7 8.1.3,
Incorrect. The statement 'Thread.dumpStack();' is not in a static context. The
simple method name 'dumpStack()' is.
I see in
<http://docs.oracle.com/javase/specs/jls/se7/html/jls-8.html#jls-8.1.3>
that is says,
"A statement or expression occurs in a static context if and only if the
innermost method, constructor, instance initializer, static initializer, field
initializer, or explicit constructor invocation statement enclosing the
statement or expression is a static method, a static initializer, the variable
initializer of a static variable, or an explicit constructor invocation
statement (??8.8.7)."
There are two contexts operating here. 'dumpStack()' occurs in a static
context established by the symbol 'Thread' and the dot. The entire expression,
or statement, 'Thread.dumpStack();' [*] occurs in a non-static context
established by the opening curly brace of the instance method definition.
but /is/ according to javac.
One reason for this possibly is that JLS 1 did not yet
define ??static context??, so the wording of the compiler
message might predate the first definition of ??static
context?? in the JLS.
[*] Why the heck do you insist on calling out 'java.lang'? It's highly
unconventional and not at all idiomatic for Java.
--
Lew
Honi soit qui mal y pense.
http://upload.wikimedia.org/wikipedia/commons/c/cf/Friz.jpg