labwork05

实验目的：

(1) 理解流的概念，掌握字节流与字符流的特点与处理差异。
(2) 掌握有关文件输入输出的常用类：FileInputStream, FileOutputStream, FileReader, FileWriter。
(3) 掌握缓冲流与转换流的使用。
(4) 掌握File类的使用。

题目要求：

创建一个学生类Student，包含name，age，ID，语文、数学、英语成绩等属性，并添加一些方法完善这个类的功能。
使用集合存储多个Student对象，并排序。
然后将排序后的信息保存为文本文件，最后从文本文件中读出这些信息并显示。

Student类

public class Student implements Comparable<Student>{
	private String id;
	private String name;
	private int age;
	private int chineseGrade;
	private int mathGrade;
	private int englishGrade;
	
	public Student() {}
	public Student(String id, String name, int age, int chineseGrade, int mathGrade, int englishGrade) {
		super();
		this.id = id;
		this.name = name;
		this.age = age;
		this.chineseGrade = chineseGrade;
		this.mathGrade = mathGrade;
		this.englishGrade = englishGrade;
	}
	
	public String getId() {
		return id;
	}
	public void setId(String id) {
		this.id = id;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
	public int getChineseGrade() {
		return chineseGrade;
	}
	public void setChineseGrade(int chineseGrade) {
		this.chineseGrade = chineseGrade;
	}
	public int getMathGrade() {
		return mathGrade;
	}
	public void setMathGrade(int mathGrade) {
		this.mathGrade = mathGrade;
	}
	public int getEnglishGrade() {
		return englishGrade;
	}
	public void setEnglishGrade(int englishGrade) {
		this.englishGrade = englishGrade;
	}
	
	@Override
	public String toString() {
		return   id + ", " + name + ", " + age + ", " + chineseGrade
				+ ", " + mathGrade + ", " + englishGrade ;
	}
	
	@Override
	public int compareTo(Student o) {
		return this.id.compareTo(o.id);
	}
}

测试类

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.io.*;

public class StudentComprehensive {
	public static void main(String[] args) throws Exception{
		
		ArrayList<Student> list = new ArrayList<Student>();

		list.add(new Student("2020001","关羽",47,88,89,62));
		list.add(new Student("2020002","赵云",55,60,95,98));
		list.add(new Student("2020003","张飞",44,72,73,70));
		list.add(new Student("2020004","马超",34,35,83,90));
		list.add(new Student("2020005","黄忠",65,92,73,54));
		
		for(Student stu:list) {
			System.out.println(stu);
		}
		System.out.println("---------------------------------");
		
		
	
		//年龄从小到大排序
		Collections.sort(list, new Comparator<Student>() {
			public int compare(Student stu1,Student stu2) {
				return stu1.getAge()-stu2.getAge();
			}
		});
		//循环输出排序后的结果
		for(Student stu:list) {
			System.out.println(stu.getId()+" "+stu.getAge()+" "+stu.getName());
		}
		
		
		
		//创建FileWriter对象，指定写入数据的目标文件
		FileWriter fileWriter = new FileWriter("StuInfo.txt");
		
		//并将结果放到StuInfo.txt文件中去
		for(Student stu:list) {
			fileWriter.write(stu.getId()+" "+stu.getAge()+" "+stu.getName()+"\r\n");
		}
		fileWriter.close();//写完之后要及时关闭
		System.out.println("----------------------------------");
		
		
		
		//创建一个字符输入缓冲流对象
		BufferedReader br = new BufferedReader(new FileReader("StuInfo.txt"));
		String str =null;
		while((str = br.readLine()) != null) {
			System.out.println(str);
		}
		br.close();
		
	}
}

测试结果

2020001, 关羽, 47, 88, 89, 62
2020002, 赵云, 55, 60, 95, 98
2020003, 张飞, 44, 72, 73, 70
2020004, 马超, 34, 35, 83, 90
2020005, 黄忠, 65, 92, 73, 54
---------------------------------
2020004 34 马超
2020003 44 张飞
2020001 47 关羽
2020002 55 赵云
2020005 65 黄忠
----------------------------------
2020004 34 马超
2020003 44 张飞
2020001 47 关羽
2020002 55 赵云
2020005 65 黄忠