50 [程序 50 文件 IO]
题目: 有五个学生, 每个学生有 3 门课的成绩, 从键盘输入以上数据 (包括学生号, 姓名, 三门课成绩), 计算出平均成绩, 将原有的数据和计算出的平均分数存放在磁盘文件 "stud" 中.
- package cskaoyan;
- import java.io.BufferedWriter;
- import java.io.File;
- import java.io.FileWriter;
- import java.io.IOException;
- class Student {
- private String id;
- private String name;
- private double math;
- private double english;
- private double c;
- 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 double getMath() {
- return math;
- }
- public void setMath(double math) {
- this.math = math;
- }
- public double getEnglish() {
- return english;
- }
- public void setEnglish(double english) {
- this.english = english;
- }
- public double getC() {
- return c;
- }
- public void setC(double c) {
- this.c = c;
- }
- public double getAverage() {
- return (this.math + this.english + this.c) / 3;
- }
- }
- public class cskaoyan50 {
- public static void main(String[] args) {
- // TODO Auto-generated method stub
- java.util.Scanner in = new java.util.Scanner(System.in);
- Student student1 = new Student();
- Student student2 = new Student();
- Student student3 = new Student();
- Student student4 = new Student();
- Student student5 = new Student();
- System.out.println("请输入 5 个同学的信息: 学生号, 姓名, 3 门成绩:");
- System.out.print("学号:");
- student1.setId(in.next());
- System.out.print("姓名:");
- student1.setName(in.next());
- System.out.print("第" + 1 + "门课成绩:");
- student1.setMath(in.nextDouble());
- System.out.print("第" + 2 + "门课成绩:");
- student1.setEnglish(in.nextDouble());
- System.out.print("第" + 3 + "门课成绩:");
- student1.setC(in.nextDouble());
- System.out.print("学号:");
- student2.setId(in.next());
- System.out.print("姓名:");
- student2.setName(in.next());
- System.out.print("第" + 1 + "门课成绩:");
- student2.setMath(in.nextDouble());
- System.out.print("第" + 2 + "门课成绩:");
- student2.setEnglish(in.nextDouble());
- System.out.print("第" + 3 + "门课成绩:");
- student2.setC(in.nextDouble());
- System.out.print("学号:");
- student3.setId(in.next());
- System.out.print("姓名:");
- student3.setName(in.next());
- System.out.print("第" + 1 + "门课成绩:");
- student3.setMath(in.nextDouble());
- System.out.print("第" + 2 + "门课成绩:");
- student3.setEnglish(in.nextDouble());
- System.out.print("第" + 3 + "门课成绩:");
- student3.setC(in.nextDouble());
- System.out.print("学号:");
- student4.setId(in.next());
- System.out.print("姓名:");
- student4.setName(in.next());
- System.out.print("第" + 1 + "门课成绩:");
- student4.setMath(in.nextDouble());
- System.out.print("第" + 2 + "门课成绩:");
- student4.setEnglish(in.nextDouble());
- System.out.print("第" + 3 + "门课成绩:");
- student4.setC(in.nextDouble());
- System.out.print("学号:");
- student5.setId(in.next());
- System.out.print("姓名:");
- student5.setName(in.next());
- System.out.print("第" + 1 + "门课成绩:");
- student5.setMath(in.nextDouble());
- System.out.print("第" + 2 + "门课成绩:");
- student5.setEnglish(in.nextDouble());
- System.out.print("第" + 3 + "门课成绩:");
- student5.setC(in.nextDouble());
- BufferedWriter bw = null;
- try {
- FileWriter fw = new FileWriter(new File("d://student.txt"));
- bw = new BufferedWriter(fw);
- bw.write("学号:" + student1.getId() + " ");
- bw.write("姓名:" + student1.getName() + " ");
- bw.write("成绩:{");
- bw.write(student1.getMath() + "" + student1.getEnglish() +" "+ student1.getC() +" ");
- bw.write("}");
- bw.write("平均成绩:" + student1.getAverage());
- bw.newLine();
- bw.write("学号:" + student2.getId() + " ");
- bw.write("姓名:" + student2.getName() + " ");
- bw.write("成绩:{");
- bw.write(student2.getMath() + "" + student2.getEnglish() +" "+ student2.getC() +" ");
- bw.write("}");
- bw.write("平均成绩:" + student2.getAverage());
- bw.newLine();
- bw.write("学号:" + student3.getId() + " ");
- bw.write("姓名:" + student3.getName() + " ");
- bw.write("成绩:{");
- bw.write(student3.getMath() + "" + student3.getEnglish() +" "+ student3.getC() +" ");
- bw.write("}");
- bw.write("平均成绩:" + student3.getAverage());
- bw.newLine();
- bw.write("学号:" + student4.getId() + " ");
- bw.write("姓名:" + student4.getName() + " ");
- bw.write("成绩:{");
- bw.write(student4.getMath() + "" + student4.getEnglish() +" "+ student4.getC() +" ");
- bw.write("}");
- bw.write("平均成绩:" + student4.getAverage());
- bw.newLine();
- bw.write("学号:" + student1.getId() + " ");
- bw.write("姓名:" + student1.getName() + " ");
- bw.write("成绩:{");
- bw.write(student1.getMath() + "" + student1.getEnglish() +" "+ student1.getC() +" ");
- bw.write("}");
- bw.write("平均成绩:" + student1.getAverage());
- bw.newLine();
- bw.write("学号:" + student5.getId() + " ");
- bw.write("姓名:" + student5.getName() + " ");
- bw.write("成绩:{");
- bw.write(student5.getMath() + "" + student5.getEnglish() +" "+ student5.getC() +" ");
- bw.write("}");
- bw.write("平均成绩:" + student5.getAverage());
- bw.newLine();
- } catch (IOException e) {
- // TODO Auto-generated catch block
- e.printStackTrace();
- } finally {
- try {
- bw.close();
- } catch (IOException e) {
- // TODO Auto-generated catch block
- e.printStackTrace();
- }
- }
- in.close();
- }
- }
来源: http://www.bubuko.com/infodetail-3193982.html