Primary knowledge Java-score Entry system

Package classtest;

Import java.util.Scanner;

public class Scorearrangement {
/**
* Select Interface (main)
*/
public static void main (string[] Args) {
Scanner sc = new Scanner (system.in);
string[] name = new string[2];
string[] Password = new string[2];
int i = 0;//main function and register function, array subscript
While (true) {
System.out.println ("select menu");
System.out.print ("A, Registration B, Landing C, exit");
String choice = Sc.next ();
Switch (choice) {
Case "a":
Case "A":
if (name[1] = = Null) {
System.out.println (name[0] + "" + password[0]);
System.out.println (name[1] + "" + password[1]);
i = Register (name, password, i);
Break
} else {
System.out.println ("registered full! ");
Break
}
Case "b":
Case "B":
Denglu (name, password);
Break
Case "c":
Case "C":
System.out.println ("exit success");
System.exit (-1);
Break
Default
System.out.println ("invalid input, re-select! ");
Break
}
}
}

/**
* Registration
*/
public static int Register (string[] a, string[] b, int X) {
Scanner sc = new Scanner (system.in);
System.out.print ("please Enter User name:");
a[x] = Sc.next ();
System.out.println ("please Enter password:");
b[x] = Sc.next ();
System.out.println ("registered successfully, User name:" + a[x] + "password:" + b[x]);
X + +;
Return x;
}

/**
* Login
*/
public static void Denglu (string[] a, string[] b) {

Scanner sc = new Scanner (system.in);
int times = 0;
System.out.println (a[0] + "" + b[0]);
System.out.println (a[1] + "" + b[1]);
While (times < 3) {
System.out.print ("please Enter User name:");
String name = Sc.next ();
System.out.println ("please Enter password:");
String Password = sc.next ();
For (int x = 0; x < 2; × x + +) {
If (name.equals (a[x]) && password.equals (b[x])) {
Fenshuguanli ();
Times = 3;
Break
} else {
SYSTEM.OUT.PRINTLN ("user name or password is incorrect, Re-enter.") ");
times++;
if (times = = 3) {
System.out.println ("3 times Input error, exit! ");
System.exit (-1); If you need to stop running, add this line of Code.
}
Break
}
}
}
}

/**
* Score Management
*/
public static void Fenshuguanli () {
string[] name = new string[100];
double[] score = new double[100];
Scanner sc = new Scanner (system.in);
int index = 1;
int number = 0;//student name array subscript
While (index = = 1) {
System.out.println ("input selection:");
SYSTEM.OUT.PRINTLN ("1, Input Student Results. ");
System.out.println ("2, revise the student Achievement. ");
System.out.println ("3, Delete Student Results. ");
System.out.println ("4, Query Individual student Results. ");
System.out.println ("5), Check all student Grades. ");
System.out.println ("6, Average Score. ");
System.out.println ("7, return to parent Menu.) ");
int choice = Sc.nextint ();
Switch (choice) {
Case 1:
If (number==99) {
System.out.println ("the data is full and cannot continue to be entered. ");
Break
}
Number = Lurufenshu (name, score, number);
Break
Case 2:
Xiugaifenshu (name, score, number);
Break
Case 3:
Shanchufenshu (name,score,number);
Break
Case 4:
Chaxunfenshu (name, score);
Break
Case 5:
Chaxunall (name,score,number);
Break
Case 6:
Average (name,score,number);
Break
Case 7:
index = 0;
Break
Default
System.out.println ("invalid selection, Re-enter.") ");
Break
}
}
}

/**
* Input Score
*/
public static int Lurufenshu (string[] name, double[] score, int Number) {
If (number > 99) {
SYSTEM.OUT.PRINTLN ("insufficient Storage space, cannot Input!") Returns to the parent menu. ");
Return number;
}
System.out.println ("Welcome lurufenshu!");
Scanner sc = new Scanner (system.in);
int index = 0;
While (index = = 0) {
System.out.println ("please Enter Student's name:");
String userName = Sc.next ();
name[number] = userName;
System.out.println ("please Enter student score:");
Double Userscore = sc.nextdouble ();
score[number] = userscore;
System.out.println ("input Information success, whether continue to Enter?") y/n ");
int index1 = 0;
While (index1 = = 0) {
String choice = Sc.next ();
Switch (choice) {
Case "y":
Case "Y":
number++;
Index1 = 1;
Break
Case "n":
Case "N":
number++;
Return number;
Default
System.out.println ("invalid instruction, Please re-enter:");
Break
}
}
}
Return number;
}

/**
* Modify Score
*/
public static void Xiugaifenshu (string[] name, double[] score, int Number) {
System.out.println ("please Enter Student's name:");
Scanner sc = new Scanner (system.in);
If (name[0]! = Null) {
String userName = Sc.next ();
int i = 0;
For (i = 0; I < number; i++) {
If (name[i].equals (userName)) {
System.out.println ("please Enter the modified score:");
score[i] = sc.nextdouble ();
System.out.println ("modified successfully! "+ name[i] +" "+ score[i] +" min ");
Break
}
}
if (i = = Number) {
System.out.println ("no information for this Student!") ");
}
} else {
System.out.println ("the Database is empty, Please enter the data First!") ");
}
}

 /**
  * Delete scores
  */
 public static int Shanchufenshu (string[]name,double[]score,int Number) {
  scanner sc=new Scanner (system.in);
  system.out.println ("please Enter the Student's name to delete the score:");
  string Username=sc.next ();
  for (int i=0;i<=number;i++) {
   if (name[i].equals (userName) &&i==99) {
    system.out.println ("delete succeeded! ");
    name[i]=null;
    score[i]=0;
   }else if (name[i].equals (userName)) {
    system.out.println ("delete succeeded! ");
    name[i]=name[i+1];
    name[i+1]=null;
    score[i]=score[i+1];
    score[i]=0;
    number--;
   }
  }
  return number;
 }

 /**
  * Query single score
  */
 public static void Chaxunfenshu (string[] name, double[] score) { Br>  system.out.println ("please Enter Student's name:");
  scanner sc = new Scanner (system.in);
  string userName = Sc.next ();
  if (name[0]! = Null) {
   int i = 0;
   for (i = 0; i < name.length-1; i++) {
    if (name[i].equals (userName)) {
     system.out.println ("the Student's score is:" + score[i] + "points. ");
     break;
    }
   }
   if (i = = Name.length-1) {
    system.out.println ("no student Information!") ");
   }
  } Else {
   system.out.println ("the database is empty, Please enter the score First!") ");
  }
 }

/**
* Check ALL Scores
*/
public static void Chaxunall (string[]name,double[]score,int Number) {
If (name[0]! = Null) {
For (int I=0;i<number;i++) {
System.out.println (name[i]+ "," +score[i]+ ");
}
} else {
System.out.println ("the Database is empty, Please enter the results First!") ");
}
}

/**
* Calculate the average score
*/
public static void Average (string[]name,double[]score,int Number) {
Double averagescore=0;
Double sum=0;
For (int I=0;i<name.length-1;i++) {
sum+=score[i];
}
System.out.println ("average divided into:" +sum/(number+1));
}
}

Primary knowledge Java-score Entry system