主函数类：
package cn.io;
import java.io.File;
import java.io.IOException;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Set;
public class iosort {
/**
* @param args
* @throws IOException
*/
/*
* 例题： 键盘录入多名学生的信息： 格式：姓名，数学成绩。语文成绩，英文成绩。
* 按总分由高到低 将学生的信息进行排列到文件里。
*思路：
* 1，使用键盘录入技术。
* 2，操作的学生信息。信息非常多，须要将信息封装成学生对象。
* 3。总分由高到低，须要排序，须要对学生对象中的总分排序。须要将多个学生对象进行容器存储。
* 4，将容器中的学生对象的信息写入到文件里。
* 容器：TreeSet
*
* 使用操作学生信息的工具类
*/
public static void main(String[] args) throws IOException {
Comparator<Student> comp = Collections.reverseOrder();
Set<Student> set = GetInfoTool.getStudents(comp);
File destfile = new File("E:\3.txt");
GetInfoTool.writrFile(set,destfile);
/* 输入
xiao,13,12,13
ss,13,24,24
de,254,4,2
over
*/
}
}
操作学生信息的工具类：
<pre class="java" name="code">package cn.io;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Comparator;
import java.util.Set;
import java.util.TreeSet;
public class GetInfoTool {
public static Set<Student> getStudents() throws IOException
{
return getStudents(null);
}
public static Set<Student> getStudents(Comparator<Student> comp) throws IOException {
BufferedReader buf = new BufferedReader(new InputStreamReader(System.in));
Set<Student> set = null;
if(comp!=null)
{
set=new TreeSet<Student>(comp);
}
else
{
set=new TreeSet<Student>();
}
String line = null;
while((line=buf.readLine())!=null)
{
if(line.contains("over")){
break;
}
String[] strs =line.split(",");
Student stu = new Student(strs[0], Integer.parseInt(strs[1]), Integer.parseInt(strs[2]), Integer.parseInt(strs[3]));
set.add(stu);
}
return set;
}
public static void writrFile(Set<Student> set, File destfile) {
BufferedWriter bfw = null;
try {
bfw = new BufferedWriter(new FileWriter(destfile));
for(Student stu:set)
{
bfw.write(stu.getName()+" "+stu.getSum());
bfw.newLine();
bfw.flush();
}
} catch (IOException e) {
e.printStackTrace();
}
finally
{
if(bfw!=null){
try {
bfw.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
学生信息类：
package cn.io;
public class Student implements Comparable<Student> {
public int getSum() {
return sum;
}
public void setSum(int sum) {
this.sum = sum;
}
private String name;
private int grade1;
private int grade2;
private int grade3;
private int sum;
public Student(String name, int grade1, int grade2, int grade3) {
super();
this.setName(name);
this.setGrade1(grade1);
this.setGrade2(grade2);
this.setGrade3(grade3);
this.sum=grade1+grade2+grade3 ;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getGrade1() {
return grade1;
}
public void setGrade1(int grade1) {
this.grade1 = grade1;
}
public int getGrade3() {
return grade3;
}
public void setGrade3(int grade3) {
this.grade3 = grade3;
}
public int getGrade2() {
return grade2;
}
public void setGrade2(int grade2) {
this.grade2 = grade2;
}
@Override
public int compareTo(Student o) {
// TODO Auto-generated method stub
int temp = this.sum-o.sum;
return temp == 0?this.name.compareTo(o.name):temp;
}
}