Java Student Performance management system source code

source code 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 Let Wei
* @since 1.0
*
* TODO Student Performance Management system
* Find, modify, delete data by learning number
*
*/
public class Littleprogram
{
static Boolean isdelete = true;
static Boolean isfind = true;
public static void Main (String [] args)/Main method, where the program starts running
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 Student Performance Management System 1.1");
System.out.println ("\t\t, please find, modify, delete data");
System.out.println ();
System.out.println ("\t####################################\n");
System.out.print ("1. Add data: \ n" +
"2. Find data: \ n" +
"3. Delete data: \ n" +
"4. Clear all data: \ n" +
"5. Print all the data to the screen \ n" +
"6. Sort the score by school number \ n" +
"7. Modify data \ n" +
"8. Statistics of the number of students recorded score \ n" +
"9. About author \ n" +
"0. Quit the program. \ n" +
"Input:");
BufferedReader in =//from end
New BufferedReader (//end-up)
New InputStreamReader (system.in))//Collection
String inputline = In.readline (); Word selection
Choice= integer.valueof (inputline). Intvalue ();
Switch (choice)
{
Case 1: {//1. Add data
String str = Lp.inputdata ();
Lp.adddata (str);
SYSTEM.OUT.PRINTLN ("Increase data success.");
TimeOut (1);
}break;
Case 2: {//2. Find data
Long find = 0;
System.out.print ("Please enter the student number you are looking for:");
BufferedReader inn =
New BufferedReader (
New InputStreamReader (system.in));
String Inputli = Inn.readline ();
Find = integer.valueof (Inputli). Longvalue ();
Lp.finddata (find);

TimeOut (2);
}break;
Case 3: {//3. Delete data
Long deletenumber = 0;
System.out.print ("Please enter the student number you want to delete:");
BufferedReader BF =
New BufferedReader (
New InputStreamReader (system.in));
String inputl = Bf.readline ();
Deletenumber = integer.valueof (inputl). Longvalue ();
Lp.deletedata (Deletenumber);
if (Isdelete)
System.out.println ("Delete data successful!");
TimeOut (1);
}break;
Case 4: {
Lp.cleardata ();//4. Clear All data
TimeOut (1);
}break;
Case 5: {
Print ();//5 the data to the screen.
TimeOut (2);
}break;
Case 6: {
Lp.numsort ()//6. Sort the score by the number of studies
System.out.println ("according to the school number from small to large sort of success!\n" +
"After sort: \ n");
Print ();
TimeOut (2);
}break;
Case 7: {
Lp.rewrite ();//7. Modify Data
TimeOut (2);
}break;
Case 8: {
int count = Lp.count ();
System.out.println ("A total of" +count+ "students have been recorded.");
TimeOut (2);
}break;
Case 9: {
System.out.print ("\t\t let Wei \ n" +
"\t\t Shanghai Electric Power College Communication engineering Department \ n" +
"\t\tqq:254482170\n");
TimeOut (4);
}break;
}while (choice!= 0);
System.out.println ("bye! ^-^");
System.exit (0);
}
public string Inputdata ()//The method of receiving data from the terminal, returning a string
Throws Ioexception,numberformatexception
{
System.out.print ("Please enter: School number name sex score \ n" +
"Separate each data by a space:");
String all = "";
try{
BufferedReader in =//from end
New BufferedReader (//end-up)
New InputStreamReader (system.in)); Collect number
String inputline = In.readline (); According
StringTokenizer str =
New StringTokenizer (Inputline, "");//Receive data separated by spaces, this class is used to extract each string
Long num = integer.valueof (Str.nexttoken ()). Longvalue ();//School Number
String name = (string) str.nexttoken (); Name
String sex = (string) str.nexttoken (); Gender
Double mark = integer.valueof (Str.nexttoken ()). Doublevalue ();//Fractions
all = String.valueof (num) + "," +
Name + "," +
Sex + "," +
String.valueof (Mark)//Put all the data in "," and then connect it into the string all
}catch (IOException e) {}
catch (NumberFormatException e) {}
Return all;//returns the string all
}
public void AddData (String str)//method of increasing data
Throws IOException
{
String S1 = "", s2= "", s3= "";
File File = new file ("Data.txt");
if (file.exists ())//if file Data.txt exists
{
try{
BufferedReader in =
New BufferedReader (
New FileReader ("Data.txt"));
while ((S1=in.readline ())!=null)
s2+=s1+ "\ n";//put each row of data in a file into a string s2
S2+=str+ "\ n"; And then put the S2 in the form of STR and put it into S2.
BufferedReader in2 =//Put character
New BufferedReader (//String S2 Also
New StringReader (S2)); is the original
PrintWriter out =//File +
New PrintWriter (//Parameter str (newly entered row of data)
New BufferedWriter (//re-written in Data.txt
New FileWriter ("Data.txt")); Overwrite the original data
while ((S3=in2.readline ())!= null)
{
Out.println (S3);
}
Out.close ();
System.out.println ("Write Data True.");
}catch (IOException e) {}
}else{
System.err.println ("File \" data\ "missing!");
}
}
public void ClearData ()//method to clear all data for data.txt
Throws IOException
{
File File = new file ("Data.txt");
if (file.exists ())//If the file is
{
try{
PrintWriter out =
New PrintWriter (
New BufferedWriter (
New FileWriter (file));
Out.print ("");//write a null character in the file data.txt, so clear the original content
Out.close (); Close File
SYSTEM.OUT.PRINTLN ("Clear Data true!");
}catch (IOException e) {}
}else{
System.err.println ("File \" data\ "missing!");
}
}
public void DeleteData (long deletenumber)//delete a piece of data
Throws Ioexception,filenotfoundexception
{
Isdelete = true;
try{
Datamap MP = new Datamap ();//Generate a container of your own writing
Long j=0;
String s1= "", s2= "", s3= "";
BufferedReader in =
New BufferedReader (
New FileReader ("Data.txt"));
while ((S1=in.readline ())!=null)
{
J=numbertokenizer (S1);
Mp.put (J,S1);
}
try{
if (Mp.containskey (string.valueof (Deletenumber). toString ()))
{
Mp.remove (Deletenumber);
}else
throw new Numbernotfoundexception ();
Collection C = mp.values ();
Iterator iter = C.iterator ();
while (Iter.hasnext ())
{
S1 = (String) iter.next ();
S3 +=s1+ "\ n";
}
BufferedReader in2 =
New BufferedReader (
New StringReader (S3));
PrintWriter out =
New PrintWriter (
New BufferedWriter (
New FileWriter ("Data.txt"));
System.out.println ("delete No" +deletenumber);
while ((S1 = In2.readline ())!=null)
{
Out.println (S1);
}
Out.close ();
}catch (numbernotfoundexception e)
{
Isdelete = false;
System.out.println (deletenumber+ "no found:(");
}
}catch (IOException e) {}
}
Public long Numbertokenizer (String s)
Throws IOException
{
StringTokenizer st =
New StringTokenizer (S, "");
Return Integer.valueof ((St.nexttoken ())). Longvalue ();
}
public void FindData (long find)/lookup data
Throws Ioexception,numbernotfoundexception
{
Isfind = true;
String s = "", findstring = "";
Long I;
Datamap dm = new Datamap ();
BufferedReader in =
New BufferedReader (
New FileReader ("Data.txt"));
while ((S=in.readline ())!=null)
{
I=numbertokenizer (s);
Dm.put (i,s);
}
In.close ();
try{
if (Dm.containskey (string.valueof (Find). ToString ()))
{
FindString = Dm.get (find);
SYSTEM.OUT.PRINTLN ("Student number" +find+ "Students ' information is:");
System.out.println (findstring);
}else
throw new Numbernotfoundexception ();
}catch (Numbernotfoundexception e) {
System.out.println (find+ "no found:(");
Isfind = false;
}
}
public static void print ()//read a text file to print data to the terminal method
Throws IOException
{
try{
BufferedReader in =
New BufferedReader (
New FileReader ("Data.txt"));
String read = "";
while (read = In.readline ())!=null)
SYSTEM.OUT.PRINTLN (read);
}catch (IOException e) {}
}
public static void TimeOut (double sec)//Pause a short time a method completely can not this function
{
Double seconds = sec;
Long T = System.currenttimemillis () + (int) (seconds*1000);
while ((System.currenttimemillis ()) <t)
;
}
public void Numsort ()//sorted by school Number
Throws IOException
{
Long i = 0;
String s = "";
try{
Dataarraylist dal = new dataarraylist ();
BufferedReader in =
New BufferedReader (
New FileReader ("Data.txt"));
while ((S=in.readline ())!=null)
{
I=numbertokenizer (s);
Dal.add (i);
}
Collections.sort (DAL);
Datamap dm = new Datamap ();
BufferedReader in2 =
New BufferedReader (
New FileReader ("Data.txt"));
while ((S=in2.readline ())!=null)
{
I=numbertokenizer (s);
Dm.put (i,s);
}
PrintWriter out =
New PrintWriter (
New BufferedWriter (
New FileWriter ("Data.txt"));
Iterator it = Dal.iterator ();
Long temp = 0;
String tempstr = "";
while (It.hasnext ())
{
temp = integer.valueof ((String) It.next ()). Longvalue ();
TempStr = Dm.get (temp);
Out.println (TEMPSTR);
}
Out.close ();
}catch (IOException e) {}
}
public void rewrite ()
Throws Ioexception,numbernotfoundexception
{
try{
System.out.print ("Please enter the student number you want to revise:");
BufferedReader in =
New BufferedReader (
New InputStreamReader (system.in));
String inputline = In.readline ();
Long num = integer.valueof (inputline). Longvalue ();
FindData (num);
if (Isfind)
{
DeleteData (num);
System.out.print ("Please re-enter the student's information:");
String str = Inputdata ();
AddData (str);
System.out.println ("rewrite true!");
}
}catch (IOException e) {}
catch (Numbernotfoundexception e) {}
}
public int count ()
Throws IOException
{

Dataarraylist dal = new dataarraylist ();
try{
String s = "";
Long i = 0;
BufferedReader in =
New BufferedReader (
New FileReader ("Data.txt"));
while ((S=in.readline ())!=null)
{
I=numbertokenizer (s);
Dal.add (i);
}
}catch (IOException e) {}
return Dal.size ();
}
}
/*
*
* @author Rangwei
* TODO This is a container we write, inheriting the public class HashMap
* The approximate function is quite an array
*
*/
Class Datamap extends hashmap//a map for storing data
{
public void put (Long i,string str)//Put the school number and data into this map
{//later a school number (key) corresponds to a person's data (value)
Put (string.valueof (i). toString (), str);
}
public void Remove (long i)/receive the number, and then delete the school number (key) and its corresponding data (value)
{
Remove (string.valueof (i). ToString (). ToString ());
}
The public String get (long i) receives a school number, and then returns the value of the key
{
String s = string.valueof (i). toString ();
if (!containskey (s))
{
System.err.println ("Not Found Key:" +s);
}
Return (String) get (s);
}
}
/*
*
* @author Rangwei
*
* TODO This class inherits ArrayList
* Used to sort by number, use it when sorting with a school number
*
*/
Class Dataarraylist extends ArrayList
{
public void Add (Long num)
{
String numtostring = string.valueof (num). toString ();
Add (numtostring);
}
}
/*
*
* @author Rangwei
*
* TODO adds a exception, mostly in the file without looking for
* The school number is thrown
*
*/
Class Numbernotfoundexception extends Exception
{
Public Numbernotfoundexception ()
{}
}