Java-08，构造方法

//用class关键字定义一个类，例如：
public class Person {
    //成员变量定义
    private int id;
    private int age = 20;
    
    //构造方法
    Person(int _id,int _age){
        id = _id;
        age = _age;
    }
    
    //方法定义
    public int getAge(){
        return age;
    }
    
    public void setAge(int i){
        age = i;
    }
    
    public int getId(){
        return id;
    }
    
    public void setId(int i){
        id = i;
    }
    
    public static void main(String args[]){
        /*
        Person p1 = new Person();
        System.out.println("Age="+p1.age);
        p1.setAge(24);
        p1.setId(1);
        System.out.println("Id="+p1.id+"\nAge="+p1.age);
        */
        Person p1 = new Person(1,20);
        Person p2 = new Person(2,24);
        System.out.println(p1.getId()+"\t"+p1.getAge());
        System.out.println(p2.getId()+"\t"+p2.getAge());
    }
}