From 5b01991917bf5ec4e4ec11c90d6623886be06303 Mon Sep 17 00:00:00 2001
From: Soullloud <97365214+Soullloud@users.noreply.github.com>
Date: Wed, 27 Sep 2023 01:01:03 +0300
Subject: [PATCH 1/2] add syntax and fix bug when multiple numbers break flow

---
 Main.java | 794 ++++++++++++++++++++++++++----------------------------
 1 file changed, 384 insertions(+), 410 deletions(-)

diff --git a/Main.java b/Main.java
index 2255c0a..c86fa06 100755
--- a/Main.java
+++ b/Main.java
@@ -7,216 +7,203 @@
 import java.util.ArrayList;
 import java.util.Scanner;
 
-class Food implements Serializable
-{
+class Food implements Serializable {
     int itemno;
-    int quantity;   
+    int quantity;
     float price;
-    
-    Food(int itemno,int quantity)
-    {
-        this.itemno=itemno;
-        this.quantity=quantity;
-        switch(itemno)
-        {
-            case 1:price=quantity*50;
+
+    Food(int itemno, int quantity) {
+        this.itemno = itemno;
+        this.quantity = quantity;
+        switch (itemno) {
+            case 1:
+                price = quantity * 50;
                 break;
-            case 2:price=quantity*60;
+            case 2:
+                price = quantity * 60;
                 break;
-            case 3:price=quantity*70;
+            case 3:
+                price = quantity * 70;
                 break;
-            case 4:price=quantity*30;
+            case 4:
+                price = quantity * 30;
                 break;
         }
     }
 }
-class Singleroom implements Serializable
-{
+
+class Singleroom implements Serializable {
     String name;
     String contact;
-    String gender;   
-    ArrayList<Food> food =new ArrayList<>();
+    String gender;
+    ArrayList<Food> food = new ArrayList<>();
 
-   
-    Singleroom()
-    {
-        this.name="";
+
+    Singleroom() {
+        this.name = "";
     }
-    Singleroom(String name,String contact,String gender)
-    {
-        this.name=name;
-        this.contact=contact;
-        this.gender=gender;
+
+    Singleroom(String name, String contact, String gender) {
+        this.name = name;
+        this.contact = contact;
+        this.gender = gender;
     }
 }
-class Doubleroom extends Singleroom implements Serializable
-{ 
+
+class doubleRoom extends Singleroom implements Serializable {
     String name2;
     String contact2;
-    String gender2;  
-    
-    Doubleroom()
-    {
-        this.name="";
-        this.name2="";
+    String gender2;
+
+    doubleRoom() {
+        this.name = "";
+        this.name2 = "";
     }
-    Doubleroom(String name,String contact,String gender,String name2,String contact2,String gender2)
-    {
-        this.name=name;
-        this.contact=contact;
-        this.gender=gender;
-        this.name2=name2;
-        this.contact2=contact2;
-        this.gender2=gender2;
+
+    doubleRoom(String name, String contact, String gender, String name2, String contact2, String gender2) {
+        this.name = name;
+        this.contact = contact;
+        this.gender = gender;
+        this.name2 = name2;
+        this.contact2 = contact2;
+        this.gender2 = gender2;
     }
 }
-class NotAvailable extends Exception
-{
+
+class NotAvailable extends Exception {
     @Override
-    public String toString()
-    {
+    public String toString() {
         return "Not Available !";
     }
 }
 
-class holder implements Serializable
-{
-    Doubleroom luxury_doublerrom[]=new Doubleroom[10]; //Luxury
-    Doubleroom deluxe_doublerrom[]=new Doubleroom[20]; //Deluxe
-    Singleroom luxury_singleerrom[]=new Singleroom[10]; //Luxury
-    Singleroom deluxe_singleerrom[]=new Singleroom[20]; //Deluxe
+class holder implements Serializable {
+    doubleRoom[] luxury_doublerrom = new doubleRoom[10]; //Luxury
+    doubleRoom[] deluxe_doublerrom = new doubleRoom[20]; //Deluxe
+    Singleroom[] luxury_singleerrom = new Singleroom[10]; //Luxury
+    Singleroom[] deluxe_singleerrom = new Singleroom[20]; //Deluxe
 }
 
-class Hotel
-{
-    static holder hotel_ob=new holder();
+class Hotel {
+    static holder hotel_ob = new holder();
     static Scanner sc = new Scanner(System.in);
-    static void CustDetails(int i,int rn)
-    {
+
+    static void CustDetails(int i, int rn) {
         String name, contact, gender;
-        String name2 = null, contact2 = null; 
-        String gender2="";
-        System.out.print("\nEnter customer name: ");
+        String name2 = null, contact2 = null;
+        String gender2 = "";
+        System.out.println("Enter customer name: ");
         name = sc.next();
         System.out.print("Enter contact number: ");
-        contact=sc.next();
+        contact = sc.next();
         System.out.print("Enter gender: ");
         gender = sc.next();
-        if(i<3)
-        {
-        System.out.print("Enter second customer name: ");
-        name2 = sc.next();
-        System.out.print("Enter contact number: ");
-        contact2=sc.next();
-        System.out.print("Enter gender: ");
-        gender2 = sc.next();
-        }      
-        
-          switch (i) {
-            case 1:hotel_ob.luxury_doublerrom[rn]=new Doubleroom(name,contact,gender,name2,contact2,gender2);
+        if (i < 3) {
+            System.out.print("Enter second customer name: ");
+            name2 = sc.next();
+            System.out.print("Enter contact number: ");
+            contact2 = sc.next();
+            System.out.print("Enter gender: ");
+            gender2 = sc.next();
+        }
+
+        switch (i) {
+            case 1:
+                hotel_ob.luxury_doublerrom[rn] = new doubleRoom(name, contact, gender, name2, contact2, gender2);
                 break;
-            case 2:hotel_ob.deluxe_doublerrom[rn]=new Doubleroom(name,contact,gender,name2,contact2,gender2);
+            case 2:
+                hotel_ob.deluxe_doublerrom[rn] = new doubleRoom(name, contact, gender, name2, contact2, gender2);
                 break;
-            case 3:hotel_ob.luxury_singleerrom[rn]=new Singleroom(name,contact,gender);
+            case 3:
+                hotel_ob.luxury_singleerrom[rn] = new Singleroom(name, contact, gender);
                 break;
-            case 4:hotel_ob.deluxe_singleerrom[rn]=new Singleroom(name,contact,gender);
+            case 4:
+                hotel_ob.deluxe_singleerrom[rn] = new Singleroom(name, contact, gender);
                 break;
-            default:System.out.println("Wrong option");
+            default:
+                System.out.println("Wrong option");
                 break;
         }
     }
-    
-    static void bookroom(int i)
-    {
+
+    static void bookRoom(int i) {
         int j;
         int rn;
-        System.out.println("\nChoose room number from : ");
+        System.out.println("Choose room number from : ");
         switch (i) {
             case 1:
-                for(j=0;j<hotel_ob.luxury_doublerrom.length;j++)
-                {
-                    if(hotel_ob.luxury_doublerrom[j]==null)
-                    {
-                        System.out.print(j+1+",");
+                for (j = 0; j < hotel_ob.luxury_doublerrom.length; j++) {
+                    if (hotel_ob.luxury_doublerrom[j] == null) {
+                        System.out.print(j + 1 + ",");
                     }
                 }
-                System.out.print("\nEnter room number: ");
-                try{
-                rn=sc.nextInt();
-                rn--;
-                if(hotel_ob.luxury_doublerrom[rn]!=null)
-                    throw new NotAvailable();
-                CustDetails(i,rn);
-                }
-                catch(Exception e)
-                {
+                System.out.println("Enter room number: ");
+                try {
+                    String roomNumber = sc.nextLine();
+                    if(!roomNumber.matches("[0-9]+")) {
+                        throw new IllegalAccessException("incorrect room number");
+                    }
+                    rn = Integer.parseInt(roomNumber);
+                    rn--;
+                    if (hotel_ob.luxury_doublerrom[rn] != null)
+                        throw new NotAvailable();
+                    CustDetails(i, rn);
+                } catch (Exception e) {
                     System.out.println("Invalid Option");
                     return;
                 }
                 break;
             case 2:
-                 for(j=0;j<hotel_ob.deluxe_doublerrom.length;j++)
-                {
-                    if(hotel_ob.deluxe_doublerrom[j]==null)
-                    {
-                        System.out.print(j+11+",");
+                for (j = 0; j < hotel_ob.deluxe_doublerrom.length; j++) {
+                    if (hotel_ob.deluxe_doublerrom[j] == null) {
+                        System.out.print(j + 11 + ",");
                     }
                 }
-                System.out.print("\nEnter room number: ");
-                try{
-                rn=sc.nextInt();
-                rn=rn-11;
-                if(hotel_ob.deluxe_doublerrom[rn]!=null)
-                    throw new NotAvailable();
-                CustDetails(i,rn);
-                }
-                catch(Exception e)
-                {
+                System.out.println("Enter room number: ");
+                try {
+                    rn = sc.nextInt();
+                    rn = rn - 11;
+                    if (hotel_ob.deluxe_doublerrom[rn] != null)
+                        throw new NotAvailable();
+                    CustDetails(i, rn);
+                } catch (Exception e) {
                     System.out.println("Invalid Option");
                     return;
                 }
                 break;
             case 3:
-                  for(j=0;j<hotel_ob.luxury_singleerrom.length;j++)
-                {
-                    if(hotel_ob.luxury_singleerrom[j]==null)
-                    {
-                        System.out.print(j+31+",");
+                for (j = 0; j < hotel_ob.luxury_singleerrom.length; j++) {
+                    if (hotel_ob.luxury_singleerrom[j] == null) {
+                        System.out.print(j + 31 + ",");
                     }
                 }
-                System.out.print("\nEnter room number: ");
-                try{
-                rn=sc.nextInt();
-                rn=rn-31;
-                if(hotel_ob.luxury_singleerrom[rn]!=null)
-                    throw new NotAvailable();
-                CustDetails(i,rn);
-                }
-                catch(Exception e)
-                {
+                System.out.println("Enter room number: ");
+                try {
+                    rn = sc.nextInt();
+                    rn = rn - 31;
+                    if (hotel_ob.luxury_singleerrom[rn] != null)
+                        throw new NotAvailable();
+                    CustDetails(i, rn);
+                } catch (Exception e) {
                     System.out.println("Invalid Option");
                     return;
                 }
                 break;
             case 4:
-                  for(j=0;j<hotel_ob.deluxe_singleerrom.length;j++)
-                {
-                    if(hotel_ob.deluxe_singleerrom[j]==null)
-                    {
-                        System.out.print(j+41+",");
+                for (j = 0; j < hotel_ob.deluxe_singleerrom.length; j++) {
+                    if (hotel_ob.deluxe_singleerrom[j] == null) {
+                        System.out.print(j + 41 + ",");
                     }
                 }
-                System.out.print("\nEnter room number: ");
-                try{
-                rn=sc.nextInt();
-                rn=rn-41;
-                if(hotel_ob.deluxe_singleerrom[rn]!=null)
-                    throw new NotAvailable();
-                CustDetails(i,rn);
-                }
-                catch(Exception e)
-                {
-                   System.out.println("Invalid Option");
+                System.out.println("Enter room number: ");
+                try {
+                    rn = sc.nextInt();
+                    rn = rn - 41;
+                    if (hotel_ob.deluxe_singleerrom[rn] != null)
+                        throw new NotAvailable();
+                    CustDetails(i, rn);
+                } catch (Exception e) {
+                    System.out.println("Invalid Option");
                     return;
                 }
                 break;
@@ -226,53 +213,51 @@ static void bookroom(int i)
         }
         System.out.println("Room Booked");
     }
-    
-    static void features(int i)
-    {
+
+    static void features(int i) {
         switch (i) {
-            case 1:System.out.println("Number of double beds : 1\nAC : Yes\nFree breakfast : Yes\nCharge per day:4000 ");
+            case 1:
+                System.out.println("Number of double beds : 1\nAC : Yes\nFree breakfast : Yes\nCharge per day:4000 ");
                 break;
-            case 2:System.out.println("Number of double beds : 1\nAC : No\nFree breakfast : Yes\nCharge per day:3000  ");
+            case 2:
+                System.out.println("Number of double beds : 1\nAC : No\nFree breakfast : Yes\nCharge per day:3000  ");
                 break;
-            case 3:System.out.println("Number of single beds : 1\nAC : Yes\nFree breakfast : Yes\nCharge per day:2200  ");
+            case 3:
+                System.out.println("Number of single beds : 1\nAC : Yes\nFree breakfast : Yes\nCharge per day:2200  ");
                 break;
-            case 4:System.out.println("Number of single beds : 1\nAC : No\nFree breakfast : Yes\nCharge per day:1200 ");
+            case 4:
+                System.out.println("Number of single beds : 1\nAC : No\nFree breakfast : Yes\nCharge per day:1200 ");
                 break;
             default:
                 System.out.println("Enter valid option");
                 break;
         }
     }
-    
-    static void availability(int i)
-    {
-      int j,count=0;
+
+    static void availability(int i) {
+        int j, count = 0;
         switch (i) {
             case 1:
-                for(j=0;j<10;j++)
-                {
-                    if(hotel_ob.luxury_doublerrom[j]==null)
+                for (j = 0; j < 10; j++) {
+                    if (hotel_ob.luxury_doublerrom[j] == null)
                         count++;
                 }
                 break;
             case 2:
-                for(j=0;j<hotel_ob.deluxe_doublerrom.length;j++)
-                {
-                    if(hotel_ob.deluxe_doublerrom[j]==null)
+                for (j = 0; j < hotel_ob.deluxe_doublerrom.length; j++) {
+                    if (hotel_ob.deluxe_doublerrom[j] == null)
                         count++;
                 }
                 break;
             case 3:
-                for(j=0;j<hotel_ob.luxury_singleerrom.length;j++)
-                {
-                    if(hotel_ob.luxury_singleerrom[j]==null)
+                for (j = 0; j < hotel_ob.luxury_singleerrom.length; j++) {
+                    if (hotel_ob.luxury_singleerrom[j] == null)
                         count++;
                 }
                 break;
             case 4:
-                for(j=0;j<hotel_ob.deluxe_singleerrom.length;j++)
-                {
-                    if(hotel_ob.deluxe_singleerrom[j]==null)
+                for (j = 0; j < hotel_ob.deluxe_singleerrom.length; j++) {
+                    if (hotel_ob.deluxe_singleerrom[j] == null)
                         count++;
                 }
                 break;
@@ -280,309 +265,298 @@ static void availability(int i)
                 System.out.println("Enter valid option");
                 break;
         }
-        System.out.println("Number of rooms available : "+count);
+        System.out.println("Number of rooms available : " + count);
     }
-    
-    static void bill(int rn,int rtype)
-    {
-        double amount=0;
-        String list[]={"Sandwich","Pasta","Noodles","Coke"};
-        System.out.println("\n*******");
+
+    static void bill(int rn, int rtype) {
+        double amount = 0;
+        String[] list = {"Sandwich", "Pasta", "Noodles", "Coke"};
+        System.out.println("*******");
         System.out.println(" Bill:-");
         System.out.println("*******");
-               
-        switch(rtype)
-        {
+
+        switch (rtype) {
             case 1:
-                amount+=4000;
-                    System.out.println("\nRoom Charge - "+4000);
-                    System.out.println("\n===============");
-                    System.out.println("Food Charges:- ");
-                    System.out.println("===============");
-                     System.out.println("Item   Quantity    Price");
-                    System.out.println("-------------------------");
-                    for(Food obb:hotel_ob.luxury_doublerrom[rn].food)
-                    {
-                        amount+=obb.price;
-                        String format = "%-10s%-10s%-10s%n";
-                        System.out.printf(format,list[obb.itemno-1],obb.quantity,obb.price );
-                    }
-                    
-                break;
-            case 2:amount+=3000;
-                    System.out.println("Room Charge - "+3000);
-                    System.out.println("\nFood Charges:- ");
-                    System.out.println("===============");
-                     System.out.println("Item   Quantity    Price");
-                    System.out.println("-------------------------");
-                    for(Food obb:hotel_ob.deluxe_doublerrom[rn].food)
-                    {
-                        amount+=obb.price;
-                        String format = "%-10s%-10s%-10s%n";
-                        System.out.printf(format,list[obb.itemno-1],obb.quantity,obb.price );
-                    }
+                amount += 4000;
+                System.out.println("Room Charge - " + 4000);
+                System.out.println("===============");
+                System.out.println("Food Charges:- ");
+                System.out.println("===============");
+                System.out.println("Item   Quantity    Price");
+                System.out.println("-------------------------");
+                for (Food obb : hotel_ob.luxury_doublerrom[rn].food) {
+                    amount += obb.price;
+                    String format = "%-10s%-10s%-10s%n";
+                    System.out.printf(format, list[obb.itemno - 1], obb.quantity, obb.price);
+                }
+
                 break;
-            case 3:amount+=2200;
-                    System.out.println("Room Charge - "+2200);
-                    System.out.println("\nFood Charges:- ");
-                    System.out.println("===============");
-                    System.out.println("Item   Quantity    Price");
-                    System.out.println("-------------------------");
-                    for(Food obb:hotel_ob.luxury_singleerrom[rn].food)
-                    {
-                        amount+=obb.price;
-                        String format = "%-10s%-10s%-10s%n";
-                        System.out.printf(format,list[obb.itemno-1],obb.quantity,obb.price );
-                    }
+            case 2:
+                amount += 3000;
+                System.out.println("Room Charge - " + 3000);
+                System.out.println("Food Charges:- ");
+                System.out.println("===============");
+                System.out.println("Item   Quantity    Price");
+                System.out.println("-------------------------");
+                for (Food obb : hotel_ob.deluxe_doublerrom[rn].food) {
+                    amount += obb.price;
+                    String format = "%-10s%-10s%-10s%n";
+                    System.out.printf(format, list[obb.itemno - 1], obb.quantity, obb.price);
+                }
                 break;
-            case 4:amount+=1200;
-                    System.out.println("Room Charge - "+1200);
-                    System.out.println("\nFood Charges:- ");
-                    System.out.println("===============");
-                    System.out.println("Item   Quantity    Price");
-                    System.out.println("-------------------------");
-                    for(Food obb: hotel_ob.deluxe_singleerrom[rn].food)
-                    {
-                        amount+=obb.price;
-                        String format = "%-10s%-10s%-10s%n";
-                        System.out.printf(format,list[obb.itemno-1],obb.quantity,obb.price );
-                    }
+            case 3:
+                amount += 2200;
+                System.out.println("Room Charge - " + 2200);
+                System.out.println("Food Charges:- ");
+                System.out.println("===============");
+                System.out.println("Item   Quantity    Price");
+                System.out.println("-------------------------");
+                for (Food obb : hotel_ob.luxury_singleerrom[rn].food) {
+                    amount += obb.price;
+                    String format = "%-10s%-10s%-10s%n";
+                    System.out.printf(format, list[obb.itemno - 1], obb.quantity, obb.price);
+                }
+                break;
+            case 4:
+                amount += 1200;
+                System.out.println("Room Charge - " + 1200);
+                System.out.println("Food Charges:- ");
+                System.out.println("===============");
+                System.out.println("Item   Quantity    Price");
+                System.out.println("-------------------------");
+                for (Food obb : hotel_ob.deluxe_singleerrom[rn].food) {
+                    amount += obb.price;
+                    String format = "%-10s%-10s%-10s%n";
+                    System.out.printf(format, list[obb.itemno - 1], obb.quantity, obb.price);
+                }
                 break;
             default:
                 System.out.println("Not valid");
         }
-        System.out.println("\nTotal Amount- "+amount);
+        System.out.println("Total Amount- " + amount);
     }
-    
-    static void deallocate(int rn,int rtype)
-    {
+
+    static void deallocate(int rn, int rtype) {
         int j;
         char w;
         switch (rtype) {
-            case 1:               
-                if(hotel_ob.luxury_doublerrom[rn]!=null)
-                    System.out.println("Room used by "+hotel_ob.luxury_doublerrom[rn].name);                
-                else 
-                {    
+            case 1:
+                if (hotel_ob.luxury_doublerrom[rn] != null)
+                    System.out.println("Room used by " + hotel_ob.luxury_doublerrom[rn].name);
+                else {
                     System.out.println("Empty Already");
-                        return;
+                    return;
                 }
                 System.out.println("Do you want to checkout ?(y/n)");
-                 w=sc.next().charAt(0);
-                if(w=='y'||w=='Y')
-                {
-                    bill(rn,rtype);
-                    hotel_ob.luxury_doublerrom[rn]=null;
+                w = sc.next().charAt(0);
+                if (w == 'y' || w == 'Y') {
+                    bill(rn, rtype);
+                    hotel_ob.luxury_doublerrom[rn] = null;
                     System.out.println("Deallocated succesfully");
                 }
-                
+
                 break;
             case 2:
-                if(hotel_ob.deluxe_doublerrom[rn]!=null)
-                    System.out.println("Room used by "+hotel_ob.deluxe_doublerrom[rn].name);                
-                else 
-                {    
+                if (hotel_ob.deluxe_doublerrom[rn] != null)
+                    System.out.println("Room used by " + hotel_ob.deluxe_doublerrom[rn].name);
+                else {
                     System.out.println("Empty Already");
-                        return;
+                    return;
                 }
                 System.out.println(" Do you want to checkout ?(y/n)");
-                 w=sc.next().charAt(0);
-                if(w=='y'||w=='Y')
-                {
-                    bill(rn,rtype);
-                    hotel_ob.deluxe_doublerrom[rn]=null;
+                w = sc.next().charAt(0);
+                if (w == 'y' || w == 'Y') {
+                    bill(rn, rtype);
+                    hotel_ob.deluxe_doublerrom[rn] = null;
                     System.out.println("Deallocated succesfully");
                 }
-                 
+
                 break;
             case 3:
-                if(hotel_ob.luxury_singleerrom[rn]!=null)
-                    System.out.println("Room used by "+hotel_ob.luxury_singleerrom[rn].name);                
-                else 
-                 {    
+                if (hotel_ob.luxury_singleerrom[rn] != null)
+                    System.out.println("Room used by " + hotel_ob.luxury_singleerrom[rn].name);
+                else {
                     System.out.println("Empty Already");
-                        return;
+                    return;
                 }
                 System.out.println(" Do you want to checkout ? (y/n)");
-                w=sc.next().charAt(0);
-                if(w=='y'||w=='Y')
-                {
-                    bill(rn,rtype);
-                    hotel_ob.luxury_singleerrom[rn]=null;
-                    System.out.println("Deallocated succesfully");
+                w = sc.next().charAt(0);
+                if (w == 'y' || w == 'Y') {
+                    bill(rn, rtype);
+                    hotel_ob.luxury_singleerrom[rn] = null;
+                    System.out.println("Deallocated successfully");
                 }
-                
+
                 break;
             case 4:
-                if(hotel_ob.deluxe_singleerrom[rn]!=null)
-                    System.out.println("Room used by "+hotel_ob.deluxe_singleerrom[rn].name);                
-                else 
-                 {    
+                if (hotel_ob.deluxe_singleerrom[rn] != null)
+                    System.out.println("Room used by " + hotel_ob.deluxe_singleerrom[rn].name);
+                else {
                     System.out.println("Empty Already");
-                        return;
+                    return;
                 }
                 System.out.println(" Do you want to checkout ? (y/n)");
-                 w=sc.next().charAt(0);
-                if(w=='y'||w=='Y')
-                {
-                    bill(rn,rtype);
-                    hotel_ob.deluxe_singleerrom[rn]=null;
-                    System.out.println("Deallocated succesfully");
+                w = sc.next().charAt(0);
+                if (w == 'y' || w == 'Y') {
+                    bill(rn, rtype);
+                    hotel_ob.deluxe_singleerrom[rn] = null;
+                    System.out.println("Deallocated successfully");
                 }
                 break;
             default:
-                System.out.println("\nEnter valid option : ");
+                System.out.println("Enter valid option : ");
                 break;
         }
     }
-    
-    static void order(int rn,int rtype)
-    {
-        int i,q;
+
+    static void order(int rn, int rtype) {
+        int i, q;
         char wish;
-         try{
-             System.out.println("\n==========\n   Menu:  \n==========\n\n1.Sandwich\tRs.50\n2.Pasta\t\tRs.60\n3.Noodles\tRs.70\n4.Coke\t\tRs.30\n");
-        do
-        {
-            i = sc.nextInt();
-            System.out.print("Quantity- ");
-            q=sc.nextInt();
-           
-              switch(rtype){
-            case 1: hotel_ob.luxury_doublerrom[rn].food.add(new Food(i,q));
-                break;
-            case 2: hotel_ob.deluxe_doublerrom[rn].food.add(new Food(i,q));
-                break;
-            case 3: hotel_ob.luxury_singleerrom[rn].food.add(new Food(i,q));
-                break;
-            case 4: hotel_ob.deluxe_singleerrom[rn].food.add(new Food(i,q));
-                break;                                                 
-        }
-              System.out.println("Do you want to order anything else ? (y/n)");
-              wish=sc.next().charAt(0); 
-        }while(wish=='y'||wish=='Y');  
+        try {
+            System.out.println("==========");
+            System.out.println("   Menu:  ");
+            System.out.println("==========");
+            System.out.println("1.Sandwich  " + " " + "Rs.50");
+            System.out.println("2.Pasta  " + " " + "   Rs.60");
+            System.out.println("3.Noodles  " + " " + " Rs.70");
+            System.out.println("4.Coke   " + " " + "   Rs.30");
+            do {
+                i = sc.nextInt();
+                System.out.print("Quantity- ");
+                q = sc.nextInt();
+
+                switch (rtype) {
+                    case 1:
+                        hotel_ob.luxury_doublerrom[rn].food.add(new Food(i, q));
+                        break;
+                    case 2:
+                        hotel_ob.deluxe_doublerrom[rn].food.add(new Food(i, q));
+                        break;
+                    case 3:
+                        hotel_ob.luxury_singleerrom[rn].food.add(new Food(i, q));
+                        break;
+                    case 4:
+                        hotel_ob.deluxe_singleerrom[rn].food.add(new Food(i, q));
+                        break;
+                }
+                System.out.println("Do you want to order anything else ? (y/n)");
+                wish = sc.next().charAt(0);
+            } while (wish == 'y' || wish == 'Y');
+        } catch (NullPointerException e) {
+            System.out.println("Room not booked");
+        } catch (Exception e) {
+            System.out.println("Cannot be done");
         }
-         catch(NullPointerException e)
-            {
-                System.out.println("\nRoom not booked");
-            }
-         catch(Exception e)
-         {
-             System.out.println("Cannot be done");
-         }
     }
 }
 
 
-class write implements Runnable
-{
+class write implements Runnable {
     holder hotel_ob;
-    write(holder hotel_ob)
-    {
-        this.hotel_ob=hotel_ob;
+
+    write(holder hotel_ob) {
+        this.hotel_ob = hotel_ob;
     }
+
     @Override
     public void run() {
-          try{
-        FileOutputStream fout=new FileOutputStream("backup");
-        ObjectOutputStream oos=new ObjectOutputStream(fout);
-        oos.writeObject(hotel_ob);
+        try {
+            FileOutputStream fout = new FileOutputStream("backup");
+            ObjectOutputStream oos = new ObjectOutputStream(fout);
+            oos.writeObject(hotel_ob);
+        } catch (Exception e) {
+            System.out.println("Error in writing " + e);
         }
-        catch(Exception e)
-        {
-            System.out.println("Error in writing "+e);
-        }         
-        
+
     }
-    
+
 }
 
 public class Main {
-    public static void main(String[] args){
-        
-        try
-        {           
-        File f = new File("backup");
-        if(f.exists())
-        {
-            FileInputStream fin=new FileInputStream(f);
-            ObjectInputStream ois=new ObjectInputStream(fin);
-            Hotel.hotel_ob=(holder)ois.readObject();
-        }
-        Scanner sc = new Scanner(System.in);
-        int ch,ch2;
-        char wish;
-        x:
-        do{
+    public static void main(String[] args) {
 
-        System.out.println("\nEnter your choice :\n1.Display room details\n2.Display room availability \n3.Book\n4.Order food\n5.Checkout\n6.Exit\n");
-        ch = sc.nextInt();
-        switch(ch){
-            case 1: System.out.println("\nChoose room type :\n1.Luxury Double Room \n2.Deluxe Double Room \n3.Luxury Single Room \n4.Deluxe Single Room\n");
-                    ch2 = sc.nextInt();
-                    Hotel.features(ch2);
-                break;
-            case 2:System.out.println("\nChoose room type :\n1.Luxury Double Room \n2.Deluxe Double Room \n3.Luxury Single Room\n4.Deluxe Single Room\n");
-                     ch2 = sc.nextInt();
-                     Hotel.availability(ch2);
-                break;
-            case 3:System.out.println("\nChoose room type :\n1.Luxury Double Room \n2.Deluxe Double Room \n3.Luxury Single Room\n4.Deluxe Single Room\n");
-                     ch2 = sc.nextInt();
-                     Hotel.bookroom(ch2);                     
-                break;
-            case 4:
-                 System.out.print("Room Number -");
-                     ch2 = sc.nextInt();
-                     if(ch2>60)
-                         System.out.println("Room doesn't exist");
-                     else if(ch2>40)
-                         Hotel.order(ch2-41,4);
-                     else if(ch2>30)
-                         Hotel.order(ch2-31,3);
-                     else if(ch2>10)
-                         Hotel.order(ch2-11,2);
-                     else if(ch2>0)
-                         Hotel.order(ch2-1,1);
-                     else
-                         System.out.println("Room doesn't exist");
-                     break;
-            case 5:                 
-                System.out.print("Room Number -");
-                     ch2 = sc.nextInt();
-                     if(ch2>60)
-                         System.out.println("Room doesn't exist");
-                     else if(ch2>40)
-                         Hotel.deallocate(ch2-41,4);
-                     else if(ch2>30)
-                         Hotel.deallocate(ch2-31,3);
-                     else if(ch2>10)
-                         Hotel.deallocate(ch2-11,2);
-                     else if(ch2>0)
-                         Hotel.deallocate(ch2-1,1);
-                     else
-                         System.out.println("Room doesn't exist");
-                     break;
-            case 6:break x;
-                
-        }
-           
-            System.out.println("\nContinue : (y/n)");
-            wish=sc.next().charAt(0); 
-            if(!(wish=='y'||wish=='Y'||wish=='n'||wish=='N'))
-            {
-                System.out.println("Invalid Option");
-                System.out.println("\nContinue : (y/n)");
-                wish=sc.next().charAt(0); 
-            }
-            
-        }while(wish=='y'||wish=='Y');    
-        
-        Thread t=new Thread(new write(Hotel.hotel_ob));
-        t.start();
-        }        
-            catch(Exception e)
-            {
-                System.out.println("Not a valid input");
+        try {
+            File f = new File("backup");
+            if (f.exists()) {
+                FileInputStream fin = new FileInputStream(f);
+                ObjectInputStream ois = new ObjectInputStream(fin);
+                Hotel.hotel_ob = (holder) ois.readObject();
             }
+            Scanner sc = new Scanner(System.in);
+            int ch, ch2;
+            char wish;
+            x:
+            do {
+
+                System.out.println("\nEnter your choice :\n1.Display room details\n2.Display room availability \n3.Book\n4.Order food\n5.Checkout\n6.Exit\n");
+                ch = sc.nextInt();
+                switch (ch) {
+                    case 1:
+                        System.out.println("\nChoose room type :\n1.Luxury Double Room \n2.Deluxe Double Room \n3.Luxury Single Room \n4.Deluxe Single Room\n");
+                        ch2 = sc.nextInt();
+                        Hotel.features(ch2);
+                        break;
+                    case 2:
+                        System.out.println("\nChoose room type :\n1.Luxury Double Room \n2.Deluxe Double Room \n3.Luxury Single Room\n4.Deluxe Single Room\n");
+                        ch2 = sc.nextInt();
+                        Hotel.availability(ch2);
+                        break;
+                    case 3:
+                        System.out.println("\nChoose room type :\n1.Luxury Double Room \n2.Deluxe Double Room \n3.Luxury Single Room\n4.Deluxe Single Room\n");
+                        ch2 = sc.nextInt();
+                        Hotel.bookRoom(ch2);
+                        break;
+                    case 4:
+                        System.out.print("Room Number -");
+                        ch2 = sc.nextInt();
+                        if (ch2 > 60)
+                            System.out.println("Room doesn't exist");
+                        else if (ch2 > 40)
+                            Hotel.order(ch2 - 41, 4);
+                        else if (ch2 > 30)
+                            Hotel.order(ch2 - 31, 3);
+                        else if (ch2 > 10)
+                            Hotel.order(ch2 - 11, 2);
+                        else if (ch2 > 0)
+                            Hotel.order(ch2 - 1, 1);
+                        else
+                            System.out.println("Room doesn't exist");
+                        break;
+                    case 5:
+                        System.out.print("Room Number -");
+                        ch2 = sc.nextInt();
+                        if (ch2 > 60)
+                            System.out.println("Room doesn't exist");
+                        else if (ch2 > 40)
+                            Hotel.deallocate(ch2 - 41, 4);
+                        else if (ch2 > 30)
+                            Hotel.deallocate(ch2 - 31, 3);
+                        else if (ch2 > 10)
+                            Hotel.deallocate(ch2 - 11, 2);
+                        else if (ch2 > 0)
+                            Hotel.deallocate(ch2 - 1, 1);
+                        else
+                            System.out.println("Room doesn't exist");
+                        break;
+                    case 6:
+                        break x;
+
+                }
+
+                System.out.println("\nContinue : (y/n)");
+                wish = sc.next().charAt(0);
+                if (!(wish == 'y' || wish == 'Y' || wish == 'n' || wish == 'N')) {
+                    System.out.println("Invalid Option");
+                    System.out.println("\nContinue : (y/n)");
+                    wish = sc.next().charAt(0);
+                }
+
+            } while (wish == 'y' || wish == 'Y');
+
+            Thread t = new Thread(new write(Hotel.hotel_ob));
+            t.start();
+        } catch (Exception e) {
+            System.out.println("Not a valid input");
+        }
     }
 }

From 69ad68575f8d68256d5025a0e348a57563e8d341 Mon Sep 17 00:00:00 2001
From: Soullloud <97365214+Soullloud@users.noreply.github.com>
Date: Wed, 27 Sep 2023 17:30:12 +0300
Subject: [PATCH 2/2] fix bug Input Validation, Thread Safety, Error Handling

---
 Main.java | 62 +++++++++++++++++++++++++++++++++++++++++++------------
 1 file changed, 49 insertions(+), 13 deletions(-)

diff --git a/Main.java b/Main.java
index c86fa06..3adc344 100755
--- a/Main.java
+++ b/Main.java
@@ -87,7 +87,7 @@ class holder implements Serializable {
 class Hotel {
     static holder hotel_ob = new holder();
     static Scanner sc = new Scanner(System.in);
-
+    static ArrayList<User> users = new ArrayList<>();
     static void CustDetails(int i, int rn) {
         String name, contact, gender;
         String name2 = null, contact2 = null;
@@ -126,6 +126,8 @@ static void CustDetails(int i, int rn) {
         }
     }
 
+
+
     static void bookRoom(int i) {
         int j;
         int rn;
@@ -140,19 +142,30 @@ static void bookRoom(int i) {
                 System.out.println("Enter room number: ");
                 try {
                     String roomNumber = sc.nextLine();
-                    if(!roomNumber.matches("[0-9]+")) {
+                    if (!roomNumber.matches("[0-9]+")) {
                         throw new IllegalAccessException("incorrect room number");
                     }
                     rn = Integer.parseInt(roomNumber);
                     rn--;
+                    if (rn < 0 || rn >= hotel_ob.luxury_doublerrom.length) {
+                        throw new IllegalArgumentException("Invalid room number");
+                    }
                     if (hotel_ob.luxury_doublerrom[rn] != null)
                         throw new NotAvailable();
                     CustDetails(i, rn);
+                } catch (NumberFormatException e) {
+                    System.out.println("Invalid room number format");
+                } catch (IllegalArgumentException e) {
+                    System.out.println(e.getMessage());
+                }catch (NotAvailable e) {
+                    System.out.println("Room not available");
                 } catch (Exception e) {
+
                     System.out.println("Invalid Option");
                     return;
                 }
                 break;
+
             case 2:
                 for (j = 0; j < hotel_ob.deluxe_doublerrom.length; j++) {
                     if (hotel_ob.deluxe_doublerrom[j] == null) {
@@ -449,7 +462,23 @@ static void order(int rn, int rtype) {
         }
     }
 }
+class User {
+    private String username;
+    private String password;
 
+    public User(String username, String password) {
+        this.username = username;
+        this.password = password;
+    }
+
+    public String getUsername() {
+        return username;
+    }
+
+    public String getPassword() {
+        return password;
+    }
+}
 
 class write implements Runnable {
     holder hotel_ob;
@@ -460,14 +489,16 @@ class write implements Runnable {
 
     @Override
     public void run() {
-        try {
-            FileOutputStream fout = new FileOutputStream("backup");
-            ObjectOutputStream oos = new ObjectOutputStream(fout);
-            oos.writeObject(hotel_ob);
-        } catch (Exception e) {
-            System.out.println("Error in writing " + e);
-        }
+        synchronized (hotel_ob) {
+            try {
+                FileOutputStream fout = new FileOutputStream("backup");
+                ObjectOutputStream oos = new ObjectOutputStream(fout);
+                oos.writeObject(hotel_ob);
+            } catch (Exception e) {
+                System.out.println("Error in writing " + e);
+            }
 
+        }
     }
 
 }
@@ -475,12 +506,17 @@ public void run() {
 public class Main {
     public static void main(String[] args) {
 
+
         try {
             File f = new File("backup");
             if (f.exists()) {
                 FileInputStream fin = new FileInputStream(f);
                 ObjectInputStream ois = new ObjectInputStream(fin);
-                Hotel.hotel_ob = (holder) ois.readObject();
+
+                synchronized (Hotel.hotel_ob) {
+                    Hotel.hotel_ob = (holder) ois.readObject();
+
+                }
             }
             Scanner sc = new Scanner(System.in);
             int ch, ch2;
@@ -543,11 +579,11 @@ else if (ch2 > 0)
 
                 }
 
-                System.out.println("\nContinue : (y/n)");
+                System.out.println("Continue : (y/n)");
                 wish = sc.next().charAt(0);
                 if (!(wish == 'y' || wish == 'Y' || wish == 'n' || wish == 'N')) {
                     System.out.println("Invalid Option");
-                    System.out.println("\nContinue : (y/n)");
+                    System.out.println("Continue : (y/n)");
                     wish = sc.next().charAt(0);
                 }
 
@@ -556,7 +592,7 @@ else if (ch2 > 0)
             Thread t = new Thread(new write(Hotel.hotel_ob));
             t.start();
         } catch (Exception e) {
-            System.out.println("Not a valid input");
+            System.out.println("Not a valid input" + e.toString());
         }
     }
 }