JAVA基础语法07

笔记 学生信息管理

• Student.java

package com.azj.model;

public class Student {
	// 成员属性：学号，姓名，性别，年龄，专业
	private String studentNo;
	private String studentName;
	private String studentSex;
	private int studentAge;
	
	private Subject studentSubject; //方案3 关联性强
	
	// 无参构造
	public Student() {

	}

	// 有参构造
	public Student(String studentNo, String studentName, String studentSex, int studentAge) {
		this.setStudentName(studentName);
		this.setStudentNo(studentNo);
		this.setStudentSex(studentSex);
		this.setStudentAge(studentAge);
	}

	/**
	 * 添加限制判断：null,进行实例化
	 * @return 专业对象信息
	 */
	public Subject getStudentSubject() {
		if(this.studentSubject==null) 
			this.studentSubject = new Subject();
		return studentSubject;
	}

	public void setStudentSubject(Subject studentSubject) {
		this.studentSubject = studentSubject;
	}

	public String getStudentNo() {
		return studentNo;
	}

	public void setStudentNo(String studentNo) {
		this.studentNo = studentNo;
	}

	public String getStudentName() {
		return studentName;
	}

	public void setStudentName(String studentName) {
		this.studentName = studentName;
	}

	public String getStudentSex() {
		return studentSex;
	}

	/**
	 * 判断性别：default male, .equals()比较的类型只能为String类型。
	 * @param studentSex
	 */
	public void setStudentSex(String studentSex) {
		if(studentSex.equals("female"))
			this.studentSex = "female";
		else 
			this.studentSex = "male";
	}

	public int getStudentAge() {
		return studentAge;
	}

	/**
	 * 给年龄限制：10-100，default 18
	 * @param studentAge
	 */
	public void setStudentAge(int studentAge) {
		if(studentAge<10 || studentAge>100)
			this.studentAge = 18;
		else
			this.studentAge = studentAge;
	}

	/**
	 * 学生自我介绍
	 * @return	返回学生的相关信息(学号，姓名，性别，年龄)
	 */
	public String introduction() {
		String str = "学生信息如下：\n学号：" + this.getStudentNo() + "\n姓名：" + this.getStudentName() + "\n性别："
				+ this.getStudentSex() + "\n年龄：" + this.getStudentAge()+"\n"+this.getStudentSubject().inform();
		return str;
	}
	/**
	 * 通过类对象引用获取相关信息
	 * @param subject
	 * @return 返回学生的相关信息(学号，姓名，性别，年龄，专业名称，专业编号，学期年限)
	 */
	public String introduction(Subject subject) {
		String str = "学生信息如下：\n学号：" + this.getStudentNo() + "\n姓名：" + this.getStudentName() + "\n性别："
				+ this.getStudentSex() + "\n年龄：" + this.getStudentAge()+"\n专业名称：" + subject.getSubjectName() + "\n专业编号：" + subject.getSubjectNo() + "\n学制年限："
						+ subject.getSubjectLife();;
		return str;
	}
}

• Subject.java

package com.azj.model;

/**
 * 专业类
 * 
 * @author zzh
 *
 */
public class Subject {

	// 成员属性：学科名称，编号，年限，报名学生信息,报名学生个数
	private String subjectName;
	private String subjectNo;
	private int subjectLife;
	private Student[] myStudent;
	private int studentNum;

	// 无参构造
	public Subject() {

	}

	// 带参构造，实现对属性的全部赋值
	public Subject(String subjectName, String subjectNo, int subjectLife) {
		// 建议使用set方法赋值，在set方法中有时会设置限制要求
		this.setSubjectName(subjectName);
		this.setSubjectNo(subjectNo);
		this.setSubjectLife(subjectLife);
	}

	/**
	 * 获取选修学生学习，如果未初始化则进行初始化
	 * 
	 * @return 学生信息
	 */
	public Student[] getMyStudent() {
		if (this.myStudent == null)
			this.myStudent = new Student[10];
		return myStudent;
	}

	public void setMyStudent(Student[] myStudent) {
		this.myStudent = myStudent;
	}

	public int getStudentNum() {
		return studentNum;
	}

	public void setStudentNum(int studentNum) {
		this.studentNum = studentNum;
	}

	public String getSubjectName() {
		return subjectName;
	}

	public void setSubjectName(String subjectName) {
		this.subjectName = subjectName;
	}

	public String getSubjectNo() {
		return subjectNo;
	}

	public void setSubjectNo(String subjectNo) {
		this.subjectNo = subjectNo;
	}

	public int getSubjectLife() {
		return subjectLife;
	}

	// 设置学制限制:>0
	public void setSubjectLife(int subjectLife) {
		if (subjectLife <= 0)
			return;
		this.subjectLife = subjectLife;
	}

	/**
	 * 专业介绍的方法
	 * 
	 * @return 专业介绍相关信息，包括名称，编号，年限
	 */
	public String inform() {
		String str = "专业信息如下：\n专业名称：" + this.getSubjectName() + "\n专业编号：" + this.getSubjectNo() + "\n学制年限："
				+ this.getSubjectLife();
		return str;
	}

	/**
	 * 1. 将学生保存到数组中 2. 学生个数保存到studentNum
	 * 
	 * @param stu
	 */
	public void addStudent(Student stu) {
		for (int i = 0; i < this.getMyStudent().length; i++)
			if (this.getMyStudent()[i] == null) {
				// 学生与专业之间的关联。this 指的是当前调用该方法的对象 ，双向连接
				stu.setStudentSubject(this);
				this.getMyStudent()[i] = stu;
				this.studentNum = i + 1;
				return;
			}
	}
}

• schoolTest.java

package com.ajz.test;
import com.azj.model.*;;
public class schoolTest {

	public static void main(String[] args) {
		// 测试 Subject
		Subject sub1 = new Subject("计算机学习与技术","J0001",4);
//		System.out.println(sub1.inform());
		System.out.println("-----------------------------");
//		Student stud = new Student("0001","小明","333",8);
//		System.out.println(stud.introduction());
//		System.out.println("-----------------------------");
//		System.out.println(new Student("0002","tom","female",19).introduction(sub1));
		System.out.println("-----------------------------");
		Student stud = new Student("0002","Tom","female",19);
		Student stud2 = new Student("0002","Tom","female",19);
//		System.out.println(stud.introduction());
		sub1.addStudent(stud);
		sub1.addStudent(stud2);
		System.out.println(sub1.getStudentNum());
	}
}