接口练习： 设计接口Action表示人的活动，抽象方法有say(String msg);eating(String food); 设计抽象类Person，成员变量name和age，重写toString()方法，省略构造方法和setter、getter方法； 定义Worker类实现Action接口继承Person类。 定义Teacher类实现Action接口继承Person类。

接口Action的代码如下：

public interface Action {
    void say(String msg);
    void eating(String food);
}

抽象类Person的代码如下：

public abstract class Person {
    protected String name;
    protected int age;
    
    @Override
    public String toString() {
        return "Name: " + name + ", Age: " + age;
    }
}

Worker类的代码如下：

public class Worker extends Person implements Action {
    public Worker(String name, int age) {
        this.name = name;
        this.age = age;
    }
    
    @Override
    public void say(String msg) {
        System.out.println(name + " says: " + msg);
    }
    
    @Override
    public void eating(String food) {
        System.out.println(name + " is eating " + food);
    }
}

Teacher类的代码如下：

public class Teacher extends Person implements Action {
    public Teacher(String name, int age) {
        this.name = name;
        this.age = age;
    }
    
    @Override
    public void say(String msg) {
        System.out.println(name + " says: " + msg);
    }
    
    @Override
    public void eating(String food) {
        System.out.println(name + " is eating " + food);
    }
}

以上代码实现了Action接口和Person抽象类，并定义了Worker和Teacher类分别实现Action接口并继承Person类。Worker和Teacher类实现了Action接口中的抽象方法say和eating，以及继承自Person类的toString方法。