类

使用对象的步骤

创建对象
类名 对象名 = new 类名();

`School center = new School();

package com.company;

/**
 * Created by ttc on 17-12-22.
 */
public class school {
            String schoolName;
            int classRoomName;
            int latNname;


            public  void teach()
            {
                System.out.println("hello");
            }

}


package com.company;

/**
 * Created by ttc on 17-12-22.
 */
public class testSchool {
    public static void main(String[] args) {
        school sl=new school();
        sl.teach();
        sl.classRoomName=10;
        sl.latNname=54;
        System.out.println(sl.classRoomName);
        System.out.println(sl.latNname);
    }

    }

image.png
定义类的方法

public 返回值类型 方法名() {
//这里编写方法的主体
}

两种情况

• 如果方法具有返回值，方法体中必须使用关键字return返回该值，返回值类型为该返回值的类型
  return 表达式；
  作用： 跳出方法、返回结果

public class Student{
    String name = "张三";
    public String  getName(){
            return name;
    }
   //……
}

• 如果方法没有返回值，返回值类型为void

public class Student{
    String name = "张三";
    public void getName(){
            
    }
   //……
}

一个景区根据游人的年龄收取不同价格的门票。请编写游人类，根据年龄段(10岁到60岁之间20元，否则免费)决定能够购买的门票价格并输出

public class JourneyPerson {
    String name;
    int age;

    public void showInfo()
    {
        String ticketInfo = ""; //定义门票价格
        if(age < 10 || age > 60)
        {
            ticketInfo = "门票免费";
        }
        else
        {
            ticketInfo = "门票价格为：20元";
        }

        System.out.println(name + "的年龄为："+ age + ticketInfo);

public class Main {

    public static void main(String[] args) {
    // write your code here
        JourneyPerson journeyPerson = new JourneyPerson();

        while (true)
        {
            Scanner scanner = new Scanner(System.in);
            System.out.println("请输入姓名，输入n退出程序");
            //创建一个游人类

            //将用户输入的姓名，赋值给游人对象journeyPerson的名字属性
            journeyPerson.name = scanner.next();
            if(journeyPerson.name.equals("n"))//代表用户想退出程序
            {
                // 退出程序
                break;
            }

            //将用户输入的年龄，赋值给游人对象journeyPerson的年龄属性
            System.out.println("请输入年龄");
            journeyPerson.age = scanner.nextInt();

            //输出该游人门票信息和个人信息showInfo
            journeyPerson.showInfo();
        }

        System.out.println("退出程序");

package com.company;

/**
 * Created by ttc on 2017/12/28.
 */
//private ,default, protected,public
public class Dog {
    private String name = "旺财"; // 昵称
    private int health = 100;     // 健康值0---100 private私有的
    private int love = 0;        // 亲密度
    private int type;//类型：1狗2企鹅
    private int kind;//品种

    public String toString()
    {
        String strKind = "";
        if(kind == 1)
        {
            strKind = "拉布拉多";
        }
        else if(kind == 2)
        {
            strKind = "雪纳瑞";
        }
        String str = "宠物的自白，我的名字叫"
                +name+"健康值是"+health+"和主人的亲密度是"+love+"我是一只"+strKind;
        return str;
    }

    public String getName() {
        return name;
    }

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

    public int getHealth() {
        return health;
    }

    public void setHealth(int health) {
        this.health = health;
    }

    public int getLove() {
        return love;
    }

    public void setLove(int love) {
        this.love = love;
    }

    public int getType() {
        return type;
    }

    public void setType(int type) {
        this.type = type;
    }

    public int getKind() {
        return kind;
    }

    public void setKind(int kind) {
        this.kind = kind;
    }
}

package com.company;

import java.util.Scanner;

public class Main {

    public static void main(String[] args) {

        Scanner scanner = new Scanner(System.in);
        System.out.println("欢迎来到宠物店");
        System.out.println("请输入宠物名字");

        String name = scanner.next();

        System.out.println("请输入宠物类型:1狗，2企鹅");
        int type = scanner.nextInt();
        if(type == 1)
        {
            Dog d = new Dog();
            System.out.println("请输入品种,1聪明的拉布拉多，2酷酷的雪纳瑞");
            int kind = scanner.nextInt();
            d.setKind(kind);
            d.setName(name);
            System.out.println(d);
        }
        else
        {
            //new 企鹅();
        }

    }
}