lokal variable 的理解

public class A {
private int x = 1;

public void test() {
int x = 0;

System.out.println(x);
System.out.println(this.x);

{
x = 2;
int y = 3;
System.out.println(x + y);
}

System.out.println(x);
}

public static void main(String[] args) {
A a = new A();
a.test();
}
}