1.interface

An interface is an agreement on a rule, which is an abstraction of behavior.
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2. Definition and use of interface

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3. Characteristics of members in the interface

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4. The relationship between interface and class

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5. Examples

Write standard javabean classes with interfaces and abstract classes
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Idea 1:
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Idea 2:
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Comparing the two ideas, the second one is more reasonable and clearer. So the following code adopts this implementation method.

package com.zjut.interfaceTest;

//因为现在外界直接创建顶层person对象没有意义，所以不想让外界直接创建人的对象
//因此，可以把Person写完抽象的类
public abstract class Person {
    
    
    private String name;
    private int age;

    public Person() {
    
    
    }

    public Person(String name, int age) {
    
    
        this.name = name;
        this.age = age;
    }

    public String getName() {
    
    
        return name;
    }

    public void setName(String name) {
    
    
        this.name = name;
    }

    public int getAge() {
    
    
        return age;
    }

    public void setAge(int age) {
    
    
        this.age = age;
    }

    @Override
    public String toString() {
    
    
        return "Person{" +
                "name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}

package com.zjut.interfaceTest;

public abstract class Coach extends Person{
    
    
    public Coach() {
    
    
    }

    public Coach(String name, int age) {
    
    
        super(name, age);
    }

    public abstract void coach();
}

package com.zjut.interfaceTest;

public abstract class Sporter extends Person{
    
    

    public Sporter() {
    
    
    }

    public Sporter(String name, int age) {
    
    
        super(name, age);
    }

    public abstract void study();
}

package com.zjut.interfaceTest;

public interface English {
    
    
    public abstract void speakEnglish();
}

package com.zjut.interfaceTest;

public class PingpangSporter extends Sporter implements English{
    
    
    public PingpangSporter() {
    
    
    }

    public PingpangSporter(String name, int age) {
    
    
        super(name, age);
    }

    @Override
    public void speakEnglish() {
    
    
         System.out.println("乒乓球运动员说英语");
    }

    @Override
    public void study() {
    
    
      System.out.println("乒乓球运动员学习如何打乒乓球");
    }
}

package com.zjut.interfaceTest;

public class PingpangCoach extends Coach implements English{
    
    
    public PingpangCoach() {
    
    
    }

    public PingpangCoach(String name, int age) {
    
    
        super(name, age);
    }

    @Override
    public void coach() {
    
    
        System.out.println("乒乓球教练教授如何打乒乓球");
    }

    @Override
    public void speakEnglish() {
    
    
        System.out.println("乒乓球教练说英语");
    }


}

package com.zjut.interfaceTest;

public class BasketballSporter extends Sporter{
    
    
    public BasketballSporter() {
    
    
    }

    public BasketballSporter(String name, int age) {
    
    
        super(name, age);
    }

    @Override
    public void study() {
    
    
        System.out.println("篮球运动员学习如何打篮球");
    }
}

package com.zjut.interfaceTest;

public class BasketballCoach extends Coach{
    
    
    public BasketballCoach() {
    
    
    }

    public BasketballCoach(String name, int age) {
    
    
        super(name, age);
    }

    @Override
    public void coach() {
    
    
        System.out.println("篮球教练教授如何打篮球");
    }
}