when the block code is execute?

[Gong James]

public class AllFinals
{
{
final Vector v;
v=new Vector();
}
public AllFinals()
{
}
public void someMethod()
{
System.out.println(v.isEmpty());
}
}
An attempt to compile and call the someMethod of the above class at runtime will cause

A) A compilation error : v is not initialized in all constructors
B) A compilation error : v is not an instance variable
C) "true" is printed on the console
D) "false" is printed on the console
The given ans is;B.which had been proved right.
But i think the block
{
final Vector v;
v=new Vector();
}
is execute once the class AllFinals is loaded,which is seems like the memebre field,as a result,the compile give me error as the ANS B said,but when the block code is execute?

[Junilu Lacar]

Not with the code that's in it, it won't. That's the point of the question. However, if the block (an initialization block) contained legal code, it would be executed each time a new class instance is created.
See the JLS section on Instance Initializers (�8.6) for details.

------------------
Junilu Lacar
Sun Certified Programmer for the Java� 2 Platform

[Bill Krieger]

"v" is not an instance variable. It's a local variable, defined inside a code block and accessible only from within that code block.

[miceal oconnor]

I think the source of confusion is the difference between a block of static initialisation code & a normal block of initialisation code.
For example
class Test {

[miceal oconnor]

Oops!! Sorry about that ..anyway I'll start again.
I think the source of confusion is the difference between a block of static initialisation code & a normal block of initialisation code.
For example
class Test {
// Normal Initialisation block
{
// code
}
}
In the case shown the initialisation block is executed every time the class is instantsiated. However if you insert a 'static' keyword in from of the opening brace the code will be executed when the class in loaded & not when it is instansiated.
I think I have that right ... anybody got any objections?

[R K Singh]

Originally posted by Gong James:
<pre>public class AllFinals
{
{
final Vector v;
v=new Vector();
}
public AllFinals()
{
}
public void someMethod()
{
System.out.println(v.isEmpty());
}
}
</pre>
.........................
But i think the block
{
final Vector v;
v=new Vector();
}
is execute once the class AllFinals is loaded,which is seems like the memebre field,as a result,the compile give me error as the ANS B said,but when the block code is execute?

Hi
this is not static block so it will be executed when an instance will be created.
but point is that " Vector v " is local variable here not a instance variable , generally we assume that after class name variable are instance variable . This is good question..... which says READ Que. CAREFULLY and MARK the blocks.

------------------
Regards
Ravish