java，

java，

/*
 //题目:编写一个学生类students,该类成员变量包括学号no、姓名name、性别sex、和年纪age，
//该类成员方法有getNo(),getName(),getSex(),getAge()和setAge().
//添加构造方法为所有变量赋初值，构造方法的四种格式
//(1)包括no，name，sex，age四个参数
//(2)包括no，name，sex三个参数
//(3)包括no，name两个参数
//(4)包括no一个参数

 * */
class Students{
	private int no;
	private String name;
	private char sex;
	private int age;


	public void setSex(char mySex){
		sex=mySex;
	}
	public void setAge(int myAge){

			age=myAge;
	}

	public void setNo(int myNO){
		no=myNO;
	}
	public int getNO() {
		System.out.println("学号："+no);
		return no;
	}
	public String getName() {
		System.out.println("姓名："+name);
		return name;
	}
	public char getSex() {
		System.out.println("性别："+sex);
		return sex;
	}
	public int getAge() {
		System.out.println("年龄："+age);
		return age;
	}
	public Students(int myNO,String myName,char mySex,int myAge ){
		no=myNO;
		name=myName;
		sex=mySex;
		if(myAge<=0){
			System.out.println("输入的年龄错误，使用通用年龄18岁");
			age=18;
		}else
			age=myAge;
	}
	public Students(int myNO,String myName,char mySex ){
		no=myNO;
		name=myName;
		sex=mySex;
	}
	public Students(int myNO,String myName){
		no=myNO;
		name=myName;

	}
	public Students(int myNO ){
		no=myNO;
	}
}


public class Test {


	public static void main(String[] args) {
		Students P1=new Students(10,"张三",'男',0);
		Students P2=new Students(10,"张三",'男');
		Students P3=new Students(10,"张三");
		Students P4=new Students(10);
		P1.getAge();
		P1.getName();
		P1.getNO();
		P1.getSex();
		System.out.println("");
		P2.getSex();
		P2.getName();
		P2.getNO();
		System.out.println("");
		P3.getNO();
		P3.getName();
		System.out.println("");
		P4.getNO();
		

	}

}