从另一个类访问表单成员

class A {
    public int x;
}

class B {
    public void accessA() {
        A a = new A();
        int y = a.x;
    }
}

class A {
    private int x;

    public int getX() {
        return x;
    }

    public void setX(int x) {
        this.x = x;
    }
}

class B {
    public void accessA() {
        A a = new A();
        int y = a.getX();
        a.setX(5);
    }
}