System.out.println("x = " + x);
System.out.println("a = " + a);
System.out.println("b = " + b);
}
static {
System.out.println("Static block initialized.");
b = a * 4;
}
public static void main(String args[]) {
meth(42);
}
}
As soon as the UseStatic class is loaded, all of the static statements are run. First, a is set to 3,
then the static block executes, which prints a message and then initializes b to a * 4 or 12. Then
main( ) is called, which calls meth( ), passing 42 to x. The three println( ) statements refer to the
two static variables a and b, as well as to the local variable x.
Here is the output of the program:
Static block initialized.
x = 42
a=3
b = 12
Outside of the class in which they are defined, static methods and variables can be used
independently of any object. To do so, you need only specify the name of their class followed
by the dot operator. For example, if you wish to call a static method from outside its class, you
can do so using the following general form:
classname.method( )
Here, classname is the name of the class in which the static method is declared. As you can
see, this format is similar to that used to call non-static methods through object-reference
variables. A static variable can be accessed in the same way--by use of the dot operator on
the name of the class. This is how Java implements a controlled version of global methods
and global variables.
Here is an example. Inside main( ), the static method callme( ) and the static variable b
are accessed through their class name StaticDemo.
class StaticDemo {
static int a = 42;
static int b = 99;
static void callme() {
System.out.println("a = " + a);
}
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