java把函數作為參數傳遞

利用反射。在use里面通過
method.invoke(tool, null);可以調用Tool里面的方法

public class Tool {
     
    public void a()// /方法a
    {
        System.out.print("tool.a()...");
    }
 
    public void b()// 方法b
    {
        System.out.print("tool.b()...");
    }
}
 
 
 
 
public class Control {
    public void invoke(int flag) {
        User user = new User();
        try {
            switch (flag) {
            case 0:
                user.use(Tool.class.getMethod("a", null));
                break;
            default:
                user.use(Tool.class.getMethod("b", null));
                break;
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
 
    }
}
 
 
 
 
 
 
 
import java.lang.reflect.Method;
 
public class User
{
    public void use(Method method)
    {
        Tool tool = new Tool();
        try {
            <span style="color: #FF0000;">method.invoke(tool, null);</span>
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
 
    public static void main(String[] args){
        Control control = new Control();
        control.invoke(0);
    }
}