Static variable in method.

[dmjpro]

I m from C and C++ programming world.
There i saw that a static variable in a method lives between two function calls.
Right??
But in JAVA it is valid.
Look at this code carefully.....

class Sample
{
 //Some code
 void test()
 {
  //Some code
  static int a; //It is not valid ... the compiler error message flashes.
  //Some code
 }
 //Some code
}
 

Plz explain ....

Kind regards,
Dmjpro.

[blazedaces]

I m from C and C++ programming world.
There i saw that a static variable in a method lives between two function calls.
Right??
But in JAVA it is valid.
Look at this code carefully.....

class Sample
{
 //Some code
 void test()
 {
  //Some code
  static int a; //It is not valid ... the compiler error message flashes.
  //Some code
 }
 //Some code
}
 

Plz explain ....

Kind regards,
Dmjpro.

You can't create static variables in a non-static method. In fact, that's probably the EXACT error that showed up when you tried to compile this... am I wrong? What error did show up? I'm curious...

Also, the entire idea of a static variable: they're static, which means they are the same for all instances of that class, means that they should be created as instance variables. It only makes sense. You can set what they are in other methods, but you can't create them there.

Hope that helped,
-blazed

[JosAH]

Java doesn't implementt that feature. In C/C++ the lexical scope of a local static
variable is the function itself (it's invisible outside that function), but the variable
'lives' forever (as long as the process lives).

You can easily mimic functionally equivalent behaviour using a static class
variable. The variable can be 'seen' in every method of the class but if other
functions promise to stay away from it, the functionality is identical.

kind regards,

Jos

[dmjpro]

You can easily mimic functionally equivalent behaviour using a static class
variable. The variable can be 'seen' in every method of the class but if other
functions promise to stay away from it, the functionality is identical.

These lines r very tough to understand.
Plz tell in simple language.
Plz.

Kind regards,
Dmjpro.

[JosAH]

These lines r very tough to understand.
Plz tell in simple language.
Plz.

Kind regards,
Dmjpro.

This piece of code using C/C++:

int foo() {
   static int bar= 0;
   return bar++;
}

Can be written in Java as follows:

private static bar= 0;
public int foo() {
   return bar++;
}

Using the Java version the variable bar can be manipulated by other class and
instance methods; if they 'promise' to stay away from it the functionality of the
two code snippets is identical.

kind regards,

Jos