public class B {
public int a = 10;
private int b = 20;
protected int c = 30;
public int getB(){
return b; }
}
public class A extends B {
public int d;
public void tryVariables() {
System.out.println(a); //允许
System.out.println(b); //不允许
System.out.println(getB()); //允许
System.out.println(c); //允许
}
}