Java学生成绩管理系统源代码

　　import Java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.StringReader;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.StringTokenizer;

/*
* Created on 2005-1-11
*/

/**
* @author 让炜
* @since 1.0
*
* TODO 学生成绩治理系统
* 通过学号查找,修改,删除数据
*
*/
public class LittleProgram
{
static boolean isDelete = true;
static boolean isFind = true;
public static void main(String [] args)//主方法,程序从这里开始运行
throws IOException,NumberNotFoundException
{
int choice=-1;
do{
LittleProgram lp = new LittleProgram();
System.out.println();
System.out.println("\t####################################");
System.out.println();
System.out.println("\t\t Java学生成绩治理系统1.1");
System.out.println("\t\t请用学号查找,修改,删除数据");
System.out.println();
System.out.println("\t####################################\n");
System.out.print("1.增加数据:\n"+
"2.查找数据:\n"+
"3.删除数据:\n"+
"4.清除所有数据:\n"+
"5.把数据全部打印到屏幕\n"+
"6.把成绩按学号排序\n"+
"7.修改数据\n"+
"8.统计已记录成绩学生数\n"+
"9.关于作者\n"+
"0.退出程序.\n" +
"输入:");
BufferedReader in = //从终
new BufferedReader( //端接
new InputStreamReader(System.in));//收数
String inputLine = in.readLine(); //字选
choice= Integer.valueOf(inputLine).intValue();//项;
switch(choice)
{
case 1: {//1.增加数据
String str = lp.inputData();
lp.addData(str);
System.out.println("增加数据成功.");
timeOut(1);
}break;
case 2: {//2.查找数据
long find = 0;