public class classCode {
    public int year;
    public int month;
    public int day;
    public void setDay(int y, int m, int d){
        year = y;
        month = m;
        day = d;
    }
    public void printDate(){
        System.out.println(year + "-" + month + "-" + day);
    }
    public static void main(String[] args) {
        // 構(gòu)造三個(gè)日期類型的對(duì)象 d1 d2 d3
        classCode Date1 = new classCode();
        classCode Date2 = new classCode();
        classCode Date3 = new classCode();

        // 對(duì)d1，d2，d3的日期設(shè)置
        Date1.setDay(2022, 8, 9);
        Date2.setDay(2023, 8, 9);
        Date3.setDay(2024, 8, 9);

        //打印日期的內(nèi)容
        Date1.printDate();
        Date2.printDate();
        Date3.printDate();
    }
}

public void setDay(int year, int month, int day){ 
    year = year;
    month = month;
    day = day; 
}

public void setDay(int year, int month, int day){
    this.year = year;
    this.month = month;
    this.day = day;
}

public static void main(String[] args) {
     // 構(gòu)造三個(gè)日期類型的對(duì)象 Date1 Date2 Date3
     Date Date1 = new Date();
     Date Date2 = new Date();
     Date Date3 = new Date();

     // 對(duì)Date1，Date2，Date3的日期設(shè)置
     Date1.setDay(2022, 8, 9);
     Date2.setDay(2023, 8, 9);
     Date3.setDay(2024, 8, 9);

     //打印日期的內(nèi)容
     Date1.printDate();
     Date2.printDate();
     Date3.printDate();
}

public void setDay(Date this, int y, int m, int d){
    this.year = y;
    this.month = m;
    this.day = d;
}
public void printDate(Date this){
    System.out.println(this.year +"-"+ this.month +"-"+ this.day);
}

public class Student {
    public String name;
    public int age;

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

    public void printStudent() {
        System.out.println(this.name + "->" + this.age);
    }

    public static void main(String[] args) {
        Student student = new Student();
        student.setStudent("zhangsan", 19);
        student.printStudent();
    }
}

public static void main(String[] args) {
    int a;
    System.out.println(a);
}// Error:(26, 28) java: 可能尚未初始化變量a.

 public static void main(String[] args) {
        // 構(gòu)造一個(gè)日期類型的對(duì)象 
        Date date = new Date();
        date.setDay(2022, 8, 9);
        //打印日期的內(nèi)容
        date.printDate();
    }//代碼可以正常通過編譯

public class Student {
    public String name;
    public int age;
    public Student(){//這是一個(gè)構(gòu)造方法
        System.out.println("不帶參數(shù)的構(gòu)造方法");
    }
    public Student(String name, int age) {//這是一個(gè)構(gòu)造方法
        System.out.println("帶參數(shù)的構(gòu)造方法");
        this.name = name;
        this.age = age;
    }
    public void setStudent(String name, int age) {
        this.name = name;
        this.age = age;
    }
    public void printStudent() {
        System.out.println(this.name + "->" + this.age);
    }
    public static void main(String[] args) {
        Student student = new Student();//這一行是構(gòu)造方法的調(diào)用
    }
}

 public Student(){//不帶參數(shù)的構(gòu)造方法
        System.out.println("不帶參數(shù)的構(gòu)造方法");
    }
    public Student(String name, int age) {//帶兩個(gè)參數(shù)的構(gòu)造方法
        System.out.println("帶參數(shù)的構(gòu)造方法");
        this.name = name;
        this.age = age;

    }

public class Work {
    public int one = 1;
    public int three = 3;
    public int two = 2;

    public void printWork() {
        System.out.println(one + "-" + two + "-" + three);
    }

    public static void main(String[] args) {
        Work work = new Work();
        work.printWork();
    }
}

public class Work {
    public int one = 1;
    public int three = 3;
    public int two = 2;

    public Work(int one, int two, int three) {
        System.out.println("帶參數(shù)的構(gòu)造方法");
        this.one = one;
        this.two = two;
        this.three = three;
    }

    public void printWork() {
        System.out.println(one + "-" + two + "-" + three);
    }

    public static void main(String[] args) {
        Work work = new Work(3, 6, 9);
        work.printWork();
    }
}

 public Work() {
        this(10, 20, 30);//調(diào)用本類當(dāng)中其他的構(gòu)造方法
        System.out.println("不帶參數(shù)的的構(gòu)造方法");
    }

    public Work(int one, int two, int three) {
        System.out.println("帶參數(shù)的構(gòu)造方法");
        this.one = one;
        this.two = two;
        this.three = three;
    }

public class HardWork {
    public int a = 10;//就地初始化
    public int b = 20;//就地初始化
    public String c = "zhangsan";//就地初始化

    public void setWork(int a,  int b, String c) {
        this.a = a;
        this.b = b;
        this.c = c;
    }

    public void printWork() {
        System.out.println(a + "-" + b + "-" + c);
    }
    public static void main(String[] args) {
        HardWork work = new HardWork();
        work.printWork();
        System.out.println();
    }
}