Java final自变量

Java 1.1 允许我们将自变量设成final 属性，方法是在自变量列表中对它们进行适当的声明。这意味着在一个方法的内部，我们不能改变自变量句柄指向的东西。如下所示：

/**

 * Created by xfyou on 2016/11/2.

 * final自变量演示

 */

public class FinalArguments {

    void with(final Gizmo g) {

        //! g = new Gizmo();    // Illegal -- g is final

        g.spin();

    }

    void without(Gizmo g) {

        g = new Gizmo();    // OK -- g not final

        g.spin();

    }

    // void f(final int i) { i++; } // Can't change

    // You can only read from a final primitive:

    int g(final int i) {

        return i + 1;

    }

    public static void main(String[] args) {

        FinalArguments bf = new FinalArguments();

        bf.without(null);

        bf.with(null);

    }

}

class Gizmo {

    public void spin() {

    }

}