I am getting ready for a java certification exam and I have seen code LIKE this in one of the practice tests: 

class Foo {  
    int x = 1;  
    public static void main(String [] args) {  
        int x = 2;  
        Foo f = new Foo();  
        f.whatever();  
    }  
    { x += x; }  // <-- what's up with this?
    void whatever() {  
        ++x;  
        System.out.println(x);  
    }  
}

My question is ... Is it valid to write code in curly braces outside a method? What are the effects of these (if any)?

java syntax braces
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