In a single sentence write the code in your class directly, it will goes under static block execution 
, sounds simple, Yes it is, typically in java to initialize static variable/ to execute some statments we need to write in this way.
public class myclass{
static{
//some statements here
}
//some variables declared here
//some functions defined here
}
Where as in Action Script 3
public class myclass{
//can write static statements here
//some variables declared here
//some functions defined here
}
Just see the example code here
package
{
import mx.controls.Alert;
public class Test
{
public static var i:int = 0;
public function Test()
{
trace(“common what you want test here “+i);
}
//static block
{
Alert.show(“Oh yes “+i);
i+=1;
}
}
}
Tags: Action script 3, Flex 3, static block