8.7_java学习_练习

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/*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（包括姓名，三门课成绩），把信息和计算出的总分数高低顺序存放在磁盘文件stud.tx思思：1，通过获取键盘录入一行数据，并将该行中的信息取出封装成学生对象。2，因为学生有很多，那么就需要存储，使用到集合，因为要对学生的总分排序所以可以用TreeSet。3，将集合的信息写入到一个文件中。*/import java.io.*;import java.util.*;class Student implements Comparable<Student>{private String name ;private  int ma,cn,en;private int sum;Student(String name, int ma, int cn, int en){this.name = name;this.ma = ma;this.cn = cn;this.en = en;sum = ma + cn + en ;}public int compareTo(Student s){int num = new Integer(this.sum).compareTo(new Integer(s.sum));if(num == 0)return this.name.compareTo(s.name);return num;}public String getName(){return name;}public int getSum(){return sum;}public int hashCode(){return name.hashCode()+sum*78;}public boolean equals(Object obj){if(!(obj instanceof Student))throw new ClassCastException("类型不匹配");Student s = (Student)obj;return this.name.equals(s.name)&&this.sum ==s.sum;}public String toString(){return name+"," + ma+" ,"+cn+", "+ en+", ";}}class StudentInfoTool{public static Set<Student> getStudents()throws IOException{BufferedReader bufr = new BufferedReader(new InputStreamReader(System.in));String line = null;Set<Student> stus = new TreeSet<Student>();while((line = bufr.readLine())!=null){if("over".equals(line))break;String[] info = line.split(",");Student stu = new Student(info[0],Integer.parseInt(info[1]),Integer.parseInt(info[2]),Integer.parseInt(info[3]));stus.add(stu);}bufr.close();return stus;}public static void writeFile(Set<Student> stus)throws IOException{BufferedWriter bufw = new BufferedWriter(new FileWriter("ftuinfo.txt"));for(Student stu : stus){bufw.write(stu.toString()+"\t");bufw.write(stu.getSum()+"");bufw.newLine();bufw.flush();}bufw.close();}}class Test1{public static void main(String[] args) throws IOException{Set<Student> stus = StudentInfoTool.getStudents();StudentInfoTool.writeFile(stus);}}
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