Almost there. Can't driver doesn't recognize variables in another class?

Question

I know this has got to be an easy fix.. but i can't figure it out.so I'll put it all here... it's a program that serves as inventory. add items. sell items. etc...
this driver will not compile while the item and inventory classes compile fine.
// Project7BDriver.java
   import java.util.Scanner;
    public class Project7BDriver
       public static void main( String[] args )
           //Start Scanner to take input
         Scanner scan = new Scanner( System.in );
           //instantiate an Inventory
         Inventory myInventory = new Inventory(3);
           //find choice and continue until user quits
         int userChoice = 0;
         while( userChoice != 4 )
            menu();
            userChoice = scan.nextInt();
       public static void menuSwitch( int choice, Inventory myInventory )
           //Start Scanner to take input
         Scanner scan = new Scanner( System.in );
         switch( choice )
              //user possibilities
            case 1:
               System.out.print("Enter name of item to be added: ");
               itemName = scan.next();
               System.out.print("Enter id of item to be added: ");
               itemId = scan.nextInt();
               System.out.print("Enter quantity of item to be added: ");
               quantityInStock = scan.nextInt();
               System.out.print("Enter suggest retail value of item to be added: $");
               suggestedRetailValue = scan.nextDouble();
               myInventory.addNewItemToInventory(itemName, itemId, quantityInStock, suggestedRetailValue);
               break;
            case 2:
               System.out.print( inventory.toString() );
               break;
            case 3:
               System.out.print("Enter id of item to be sold: ");
               identification = scan.nextInt();
               System.out.print("Enter quantity of item to be sold: ");          
               sellQuantity = scan.nextInt();
               inventory.sellItem(identification, sellQuantity);
            case 4:
               System.out.println("\nGoodbye!");
               break;
            default:
               System.out.println("Sorry, invalid choice");
       public static void menu()
         System.out.println("\nInventory");
         System.out.println("*********");
         System.out.println("1: Add item to inventory");
         System.out.println("2: Print inventory");
         System.out.println("3: Sell item");
         System.out.println("4: Quit");
         System.out.print("\nEnter your choice: ");
   import java.text.NumberFormat;
    public class Inventory
        //INSTANCE VARIABLES
      private Item[] items;
      private double totalInventoryValue;
      private int numOfItemsInInventory;
      //CONSTRUCTOR
       public Inventory( int capacity )
         items = new Item[capacity];
         totalInventoryValue = 0.0;
         numOfItemsInInventory = 0;
        //METHODS
       public void increaseArraySize()
         Item[] temp = new Item[items.length + 3];
         for (int i = 0; i<items.length; i++)
            temp[i] = items;
items = temp;     
public void addNewItemToInventory (String itemName, int itemId, int quantityInStock,
                                                            double suggestedRetailValue)
if (numOfItemsInInventory == items.length)
increaseArraySize();
items[numOfItemsInInventory] = new Item (itemName, itemId, quantityInStock,
                                                                 suggestedRetailValue);
numOfItemsInInventory++;
totalInventoryValue = totalInventoryValue + suggestedRetailValue*quantityInStock;                                                                           
public void sellItem(int identification, int sellQuantity)
int indexItem = -1;
for (int j =0; j<numOfItemsInInventory; j++)
if(items[j].getID() == identification)
indexItem = j;
if(indexItem == -1)
System.out.println("The item you are searching for could not be found.\n " +
                         "Sale not completed.");
else
if(sellQuantity > items[indexItem].getQuantity())
System.out.println("It is not possible to buy more items than we have in stock.\n" +
                              "Sale not completed.");
else
totalInventoryValue -= items[indexItem].getValue()*sellQuantity;               
numOfItemsInInventory -= sellQuantity;
public String toString()
NumberFormat fmt = NumberFormat.getCurrencyInstance();
String result = "Item ID\t\tItem Name\t\tItem Quantity\t\tRetail Value";
result += "\n-------\t\t---------\t\t-------------\t\t------------";
for( int i = 0; i < numOfItemsInInventory; i++ )
result += "\n" + items[ i ];
result += "\n\nTotal value of inventory: " + fmt.format( totalInventoryValue );
return result;
} import java.text.NumberFormat;
public class Item
     //INSTANCE VARIABLES
     //name of item
private String itemName;
     //id of item
private int itemID;
     //present quantity of item in stock
private int quantityInStock;
     //suggested price for item
private double suggestedRetailValue;
     //CONSTRUCTOR
public Item( String name, int id, int quantity, double value )
itemName = name;
itemID = id;
quantityInStock = quantity;
suggestedRetailValue = value;
     //CLASS GETTERS
public String getName()
return itemName;
public int getID()
return itemID;
public int getQuantity()
return quantityInStock;
public double getValue()
return suggestedRetailValue;
     //CLASS SETTERS
public void setName( String name )
itemName = name;
public void setID( int id )
itemID = id;
public void setQuantity( int quantity )
quantityInStock = quantity;
public void setValue( double value )
suggestedRetailValue = value;
     //TOSTRING method
public String toString()
NumberFormat fmt = NumberFormat.getCurrencyInstance();
String result = "" + itemID + "\t\t\t" + itemName + "\t\t" + quantityInStock + "\t\t\t" + fmt.format( suggestedRetailValue );
return result;

Answer 1

ahhh okay thanks a whole lot!!one more thing.. everything compiles.. but i can't figure a few things out.. even after debugging..when i add items to inventory.. it has null in the list of items...also.. I'm just having trouble with selling items.. here'e the code. if someone could run it and explain how to correct the errors that would be great
   import java.util.Scanner;
    public class Project7BDriver
       public static void main( String[] args )
           //Start Scanner to take input
         Scanner scan = new Scanner( System.in );
           //instantiate an Inventory
         Inventory myInventory = new Inventory(3);
           //find choice and continue until user quits
         int choice = 0;
         while( choice != 4 )
            menu();
            choice = scan.nextInt();
            menuSwitch(choice, myInventory);
       public static void menuSwitch( int choice, Inventory myInventory )
           //Start Scanner to take input
         Scanner scan = new Scanner( System.in );
         switch( choice )
              //user possibilities
            case 1:
               System.out.print("Enter name of item to be added: ");
               String itemName = scan.next();
               System.out.print("Enter id of item to be added: ");
               int itemId = scan.nextInt();
               System.out.print("Enter quantity of item to be added: ");
               int quantityInStock = scan.nextInt();
               System.out.print("Enter suggest retail value of item to be added: $");
               double suggestedRetailValue = scan.nextDouble();
               myInventory.addNewItemToInventory(itemName, itemId, quantityInStock, suggestedRetailValue);
               break;
            case 2:
               System.out.print( myInventory.toString() );
               break;
            case 3:
               System.out.print("Enter id of item to be sold: ");
               int identification = scan.nextInt();
               System.out.print("Enter quantity of item to be sold: ");          
               int sellQuantity = scan.nextInt();
               myInventory.sellItem(identification, sellQ2uantity);
               break;
            case 4:
               System.out.println("\nGoodbye!");
               break;
            default:
               System.out.println("Sorry, invalid choice");
       public static void menu()
         System.out.println("\nInventory");
         System.out.println("*********");
         System.out.println("1: Add item to inventory");
         System.out.println("2: Print inventory");
         System.out.println("3: Sell item");
         System.out.println("4: Quit");
         System.out.print("\nEnter your choice: ");
   import java.text.NumberFormat;
    public class Item
        //INSTANCE VARIABLES
        //name of item
      private String itemName;
        //id of item
      private int itemID;
        //present quantity of item in stock
      private int quantityInStock;
        //suggested price for item
      private double suggestedRetailValue;
        //CONSTRUCTOR
       public Item( String name, int id, int quantity, double value )
         itemName = name;
         itemID = id;
         quantityInStock = quantity;
         suggestedRetailValue = value;
        //CLASS GETTERS
       public String getName()
         return itemName;
       public int getID()
         return itemID;
       public int getQuantity()
         return quantityInStock;
       public double getValue()
         return suggestedRetailValue;
        //CLASS SETTERS
       public void setName( String name )
         itemName = name;
       public void setID( int id )
         itemID = id;
       public void setQuantity( int quantity )
         quantityInStock = quantity;
       public void setValue( double value )
         suggestedRetailValue = value;
        //TOSTRING method
       public String toString()
         NumberFormat fmt = NumberFormat.getCurrencyInstance();
         String result = "" + itemID + "\t\t\t" + itemName + "\t\t" + quantityInStock + "\t\t\t" + fmt.format( suggestedRetailValue );
         return result;
   import java.text.NumberFormat;
    public class Inventory
        //INSTANCE VARIABLES
      private Item[] items;
      private double totalInventoryValue;
      private int numOfItemsInInventory;
      //CONSTRUCTOR
       public Inventory( int capacity )
         items = new Item[capacity];
         totalInventoryValue = 0.0;
         numOfItemsInInventory = 0;
        //METHODS
       public void increaseArraySize()
         Item[] temp = new Item[items.length + 3];
         for (int i = 0; i<items.length; i++)
            temp[i] = items;
items = temp;     
public void addNewItemToInventory (String itemName, int itemId, int quantityInStock,
                                                            double suggestedRetailValue)
if (numOfItemsInInventory == items.length)
increaseArraySize();
items[numOfItemsInInventory] = new Item (itemName, itemId, quantityInStock,
                                                                 suggestedRetailValue);
numOfItemsInInventory += quantityInStock;
totalInventoryValue = totalInventoryValue + suggestedRetailValue*quantityInStock;                                                                           
public void sellItem(int identification, int sellQuantity)
int indexItem = -1;
for (int j =0; j<numOfItemsInInventory; j++)
if(items[j].getID() == identification)
indexItem = j;
if(indexItem == -1)
System.out.println("The item you are searching for could not be found.\n " +
                         "Sale not completed.");
else
if(sellQuantity > items[indexItem].getQuantity())
System.out.println("It is not possible to buy more items than we have in stock.\n" +
                              "Sale not completed.");
else
totalInventoryValue -= items[indexItem].getValue()*sellQuantity;          
numOfItemsInInventory -= sellQuantity;
public String toString()
NumberFormat fmt = NumberFormat.getCurrencyInstance();
String result = "Item ID\t\tItem Name\t\tItem Quantity\t\tRetail Value";
result += "\n-------\t\t---------\t\t-------------\t\t------------";
for( int i = 0; i < numOfItemsInInventory; i++ )
result += "\n" + items[ i ];
result += "\n\nTotal value of inventory: " + fmt.format( totalInventoryValue );
return result;