Function call instance: the student management system (the optimized version above). A window is displayed .,

Function call instance: the student management system (the optimized version above). A window is displayed .,

1 package classwork308; 2/* 3 * student management system 4 */5 import javax. swing. JOptionPane; 6 7 public class Method_StudentManage {8 9/****** management account *****/10 public static String [] manager = {"", "B"}; 11/***** manage password *****/12 public static int [] password = {1, 2 }; 13/***** Student name array *****/14 public static String [] name = new String [30]; 15/***** student ID array *****/16 public static int [] code = new int [30]; 17/***** Student Score array *****/18 Public static int [] grade = new int [30]; 19/***** record the number of students *****/20 public static int number = 0; 21 22 public static void main (String [] args) {23 register (); 24} 25 26 // Administrator Logon 27 public static void register () {28 JOptionPane. showMessageDialog (null, "Welcome! "); 29 int a =-1, B = 0; 30 while (true) {31 String str = JOptionPane. showInputDialog (null, "Enter the user name"); 32 String str1 = JOptionPane. showInputDialog (null, "Enter Password"); 33 int temp = Integer. parseInt (str1); 34 for (int I = 0; I <manager. length; I ++) {35 if (str. equals (manager [I]) & temp = password [I]) {// 36 OS (); 37 a = 1; 38} 39} 40 if (a =-1) {41 if (B = 3) {42 JOptionPane. showMessageDialog (null, "invalid user"); 43 System. exit (0); 44} 45 JOptionPane. showMessageDialog (null, "incorrect user name or password"); 46 B ++; 47} 48} 49} 50 // Select page 51 public static void OS () {52 while (true) {53 String s = JOptionPane. showInputDialog (null, "1. Add \ n2, display \ n3, delete \ n4, QUERY \ n5, modify \ n6, sort \ n7, and exit \ n "); 54 int temp = Integer. parseInt (s); 55 switch (temp) {56 case 1: 57 add (); 58 break; 59 case 2: 60 show (); 61 break; 62 case 3: 63 delete (); 64 break; 65 case 4: 66 demand (); 67 break; 68 case 5: 69 modification (); 70 break; 71 case 6: 72 sort (); 73 break; 74 case 7: 75 System. exit (0); 76 break; 77 78 default: 79 JOptionPane. showMessageDialog (null, "Enter the number between 1 and 7"); 80 break; 81} 82} 83} 84 // add 85 public static void add () {86 String str1 = JOptionPane. showInputDialog (null, "Enter your student ID"); 87 String str2 = JOptionPane. showInputDialog (null, "Enter name"); 88 String str3 = JOptionPane. showInputDialog (null, "Enter the score"); 89 int temp1 = Integer. parseInt (str1); 90 int temp3 = Integer. parseInt (str3); 91 code [number] = temp1; 92 name [number] = str2; 93 grade [number] = temp3; 94 number ++; 95} 96 // delete 97 public static void delete () {98 String str = JOptionPane. showInputDialog (null, "Enter name"); 99 int a =-1; 100 for (int I = 0; I <number; I ++) {101 if (str. equals (name [I]) {102 for (int j = I; j <number-1; j ++) {103 name [j] = name [j + 1]; 104 code [j] = code [j + 1]; 105 grade [j] = grade [j + 1]; 106 107} 108 a = 1; 109 number --; 110 show (); 111 break; 112} 113} 114 if (a =-1) {115 JOptionPane. showMessageDialog (null, "student not found"); 116} 117} 118 // modify 119 public static void modification () {120 String str = JOptionPane. showInputDialog (null, "Enter name"); 121 int a =-1; 122 for (int I = 0; I <number; I ++) {123 if (str. equals (name [I]) {124 a = I; 125 String str1 = JOptionPane. showInputDialog (null, "Enter your student ID"); 126 String str2 = JOptionPane. showInputDialog (null, "Enter the score"); 127 int temp1 = Integer. parseInt (str1); 128 int temp2 = Integer. parseInt (str2); 129 name [I] = JOptionPane. showInputDialog (null, "Enter name"); 130 code [I] = temp1; 131 grade [I] = temp2; 132 show (); 133} 134} 135 if (a =-1) {136 JOptionPane. showMessageDialog (null, "student not found"); 137} 138 139} 140 // query 141 public static void demand () {142 String str = JOptionPane. showInputDialog (null, "Enter name"); 143 int a =-1; 144 for (int I = 0; I <number; I ++) {145 if (str. equals (name [I]) {146 a = I; 147 String s = "student ID name Score \ n "; 148 s = s + code [I] + "" + name [I] + "" + grade [I]; 149 JOptionPane. showMessageDialog (null, s); 150} 151} 152 if (a =-1) {153 JOptionPane. showMessageDialog (null, "student not found"); 154} 155} 156 // sort by score in descending order 157 public static void sort () {158 int temp, temp1; 159 String temp3; 160 for (int I = 0; I <number-1; I ++) {161 for (int j = I + 1; j <number; j ++) {162 if (grade [I] <grade [j]) {163 temp = grade [I]; 164 grade [I] = grade [j]; 165 grade [j] = temp; 166 temp1 = code [I]; 167 code [I] = code [j]; 168 code [j] = temp1; 169 temp3 = name [I]; 170 name [I] = name [j]; 171 name [j] = temp3; 172} 173} 174 show (); 176} 177 // display all student information 178 public static void show () {179 String s = "student ID name Score \ n"; 180 for (int I = 0; I <number; I ++) {181 s = s + code [I] + "" + name [I] + "+ grade [I] +" \ n "; 182} 183 JOptionPane. showMessageDialog (null, s); 184} 185}