JAVA 基础编程练习题50 【程序 50 文件 IO】

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();
}
}