Hiya,
I am new to java, I have a very fast paced class and I am learning as much as I can as quickly as I can. I have previous experince with C++ but it will not help here. My Question:

WHY WILL MY PROGRAM NOT RUN!!??
*It compiles and creates a class but does nothing.
*
Here is the code:

class Mobilephone { //class name and attributes
public static void main(String []args) {
}
    private int SerialNumber; //serial number of product
    private int ItemNumber; //item # of product
    private double UnitsStock; //# of units in stock
    private double UnitPrice; //Price per unit
    private double InventoryValue; //The dollar value of the inventory in stock
    private String Department; //The department the product belongs to
    private String ProductName; //product name



//constructor

 public Mobilephone (int item, int serial, double units, double price, double value, String product, String Dept) {

    ItemNumber = item;
    SerialNumber = serial;
    UnitsStock = units;
    UnitPrice = price;
    InventoryValue = value;
    ProductName = product;
    Department = Dept;



} //end constructor

///getter and setter methods for Mobilephone


public void setItemNumber (int item) { //setter for item number
    this.ItemNumber = item;
} //end setter item number
public int getItemNumber() { //getter for item number
    return ItemNumber;
} //end getter item number


public void setSerialNumber (int serial) { //setter for serial number
    this.SerialNumber = serial;
}//end setter for serial number
public int getSerialNumber() { //getter for serial number
    return SerialNumber;
}//end getter for serial number


public void setUnitsStock (double units) { //setter for units in stock
    this.UnitsStock = units;
} //end setter units in stock
public double getUnitsStock() { //getter for units in stock
    return UnitsStock;
} //end getter units in stock


public void setUnitPrice (double price) { //setter for unit price
    this.UnitPrice = price;
} //end setter unit price
public double getUnitPrice() { //getter for unit price
    return UnitPrice;
} //end getter for unit price


public void setInventoryValue (double value) { //setter for inventory value
    this.InventoryValue = value;
} //end setter inventory value
public double getInventoryValue() { //getter for Inventory Value
    return InventoryValue;
} //end getter for Inventory Value


public void setProductName (String product) { //setter for product name
    this.ProductName = product;
} //end setter product name
public String getProductName() { //getter for product name
    return ProductName;
} //end getter product name


public void setDepartment (String dept) { //setter for department
    this.Department = dept;
} //end setter Department
public String getDepartment() { //getter for department
    return Department;
} //end getter Department



//calculate individual product inventory value

public double getInventoryStockValue(){
    return UnitsStock * UnitPrice;
}//end calculate individual product inventory value


//calculate total inventory value

public double calculateInventory(){
    return UnitPrice * UnitsStock;
}//end calculate total inventory value

///end getter and setter methods for Mobilephone

} //end class Mobilephone

Chuck that into editor and save as .java. Javac and creates class. Run java and nothing happends...Annoying.

The public static void main(String[] args) method is where you put what you want your class to do when it is run. Your main method does nothing as there is nothing in the {}, so you are literally telling your class to do nothing.

nothing happens to you codes as you try to run the program because you never use the methods in it.

try to visit some java tutorials ..or you can just try to study my code. so that you can make your own code..

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package googleproblem;

/**
 *
 * @author mtangpos
 */
public class GoogleProblem {

    public static void main(String[] args) {
        class Mobilephone { //class name and attributes

            private int SerialNumber; //serial number of product
            private int ItemNumber; //item # of product
            private double UnitsStock; //# of units in stock
            private double UnitPrice; //Price per unit
            private double InventoryValue; //The dollar value of the inventory in stock
            private String Department; //The department the product belongs to
            private String ProductName; //product name
//constructor

            public Mobilephone(int item, int serial, double units, double price, double value, String product, String Dept) {
                this.ItemNumber = item;
                this.SerialNumber = serial;
                this.UnitsStock = units;
                this.UnitPrice = price;
                this.InventoryValue = value;
                this.ProductName = product;
                this.Department = Dept;
            } //end constructor
///getter and setter methods for Mobilephone

            public void setItemNumber(int item) { //setter for item number
                this.ItemNumber = item;
            } //end setter item number

            public int getItemNumber() { //getter for item number
                return ItemNumber;
            } //end getter item number

            public void setSerialNumber(int serial) { //setter for serial number
                this.SerialNumber = serial;
            }//end setter for serial number

            public int getSerialNumber() { //getter for serial number
                return SerialNumber;
            }//end getter for serial number

            public void setUnitsStock(double units) { //setter for units in stock
                this.UnitsStock = units;
            } //end setter units in stock

            public double getUnitsStock() { //getter for units in stock
                return UnitsStock;
            } //end getter units in stock

            public void setUnitPrice(double price) { //setter for unit price
                this.UnitPrice = price;
            } //end setter unit price

            public double getUnitPrice() { //getter for unit price
                return UnitPrice;
            } //end getter for unit price

            public void setInventoryValue(double value) { //setter for inventory value
                this.InventoryValue = value;
            } //end setter inventory value

            public double getInventoryValue() { //getter for Inventory Value
                return InventoryValue;
            } //end getter for Inventory Value

            public void setProductName(String product) { //setter for product name
                this.ProductName = product;
            } //end setter product name

            public String getProductName() { //getter for product name
                return ProductName;
            } //end getter product name

            public void setDepartment(String dept) { //setter for department
                this.Department = dept;
            } //end setter Department

            public String getDepartment() { //getter for department
                return Department;
            } //end getter Department
//calculate individual product inventory value

            public double getInventoryStockValue() {
                return UnitsStock * UnitPrice;
            }//end calculate individual product inventory value
//calculate total inventory value

            public double calculateInventory() {
                return UnitPrice * UnitsStock;
            }//end calculate total inventory value
///end getter and setter methods for Mobilephone
        } //end class Mobilephone

        //_____________________________________________________________

        //simple example on how to use the methods 
        //constructor
        Mobilephone mp = new Mobilephone(1, 1, 1, 1000, 1, "iphone", "mobile_department");

        //if you want to calculateInventory
        System.out.println("calculateInventory= " + mp.calculateInventory());

        //if you want to getDepartment();
        System.out.println("getDepartment= " + mp.getDepartment());

        //if you want to getInventoryStockValue();
        System.out.println("getInventoryStockValue= " + mp.getInventoryStockValue());

        //if you want to getInventoryValue();
        System.out.println("getInventoryValue =" + mp.getInventoryValue());

        //if you want to getItemNumber();
        System.out.println("getItemNumber= " + mp.getItemNumber());

        //if you want to getProductName();
        System.out.println("getProductName= " + mp.getProductName());

        //if you want to getSerialNumber();
        System.out.println(" getSerialNumber =" + mp.getSerialNumber());

        //if you want to getUnitPrice()
        System.out.println("getUnitPrice =" + mp.getUnitPrice());

        //if you want to getUnitsStock()
        System.out.println("getUnitsStock = " + mp.getUnitsStock());


        //___________________________
        //if you want to set the values just use the setters method
        //sample
        //mp.setDepartment("blabla");
        //ans so on....

    }
}

hai mtangpos16,

i have done some modifications to your code

you can not write a class inside a main method because main() method is starting point for creating objects but not starting point of the class creation/definition/declaration.

i think your code would be like as follows

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package googleproblem;

/**
 *
 * @author mtangpos
 */
public class GoogleProblem 
{

    public static void main(String[] args) {    

        Mobilephone mp = new Mobilephone(1, 1, 1, 1000, 1, "iphone", "mobile_department");

        //if you want to calculateInventory
        System.out.println("calculateInventory= " + mp.calculateInventory());

        //if you want to getDepartment();
        System.out.println("getDepartment= " + mp.getDepartment());

        //if you want to getInventoryStockValue();
        System.out.println("getInventoryStockValue= " + mp.getInventoryStockValue());

        //if you want to getInventoryValue();
        System.out.println("getInventoryValue =" + mp.getInventoryValue());

        //if you want to getItemNumber();
        System.out.println("getItemNumber= " + mp.getItemNumber());

        //if you want to getProductName();
        System.out.println("getProductName= " + mp.getProductName());

        //if you want to getSerialNumber();
        System.out.println(" getSerialNumber =" + mp.getSerialNumber());

        //if you want to getUnitPrice()
        System.out.println("getUnitPrice =" + mp.getUnitPrice());

        //if you want to getUnitsStock()
        System.out.println("getUnitsStock = " + mp.getUnitsStock());       

    }



class Mobilephone { //class name and attributes

            private int SerialNumber; //serial number of product
            private int ItemNumber; //item # of product
            private double UnitsStock; //# of units in stock
            private double UnitPrice; //Price per unit
            private double InventoryValue; //The dollar value of the inventory in stock
            private String Department; //The department the product belongs to
            private String ProductName; //product name
//constructor

            public Mobilephone(int item, int serial, double units, double price, double value, String product, String Dept) {
                this.ItemNumber = item;
                this.SerialNumber = serial;
                this.UnitsStock = units;
                this.UnitPrice = price;
                this.InventoryValue = value;
                this.ProductName = product;
                this.Department = Dept;
            } //end constructor
///getter and setter methods for Mobilephone

            public void setItemNumber(int item) { //setter for item number
                this.ItemNumber = item;
            } //end setter item number

            public int getItemNumber() { //getter for item number
                return ItemNumber;
            } //end getter item number

            public void setSerialNumber(int serial) { //setter for serial number
                this.SerialNumber = serial;
            }//end setter for serial number

            public int getSerialNumber() { //getter for serial number
                return SerialNumber;
            }//end getter for serial number

            public void setUnitsStock(double units) { //setter for units in stock
                this.UnitsStock = units;
            } //end setter units in stock

            public double getUnitsStock() { //getter for units in stock
                return UnitsStock;
            } //end getter units in stock

            public void setUnitPrice(double price) { //setter for unit price
                this.UnitPrice = price;
            } //end setter unit price

            public double getUnitPrice() { //getter for unit price
                return UnitPrice;
            } //end getter for unit price

            public void setInventoryValue(double value) { //setter for inventory value
                this.InventoryValue = value;
            } //end setter inventory value

            public double getInventoryValue() { //getter for Inventory Value
                return InventoryValue;
            } //end getter for Inventory Value

            public void setProductName(String product) { //setter for product name
                this.ProductName = product;
            } //end setter product name

            public String getProductName() { //getter for product name
                return ProductName;
            } //end getter product name

            public void setDepartment(String dept) { //setter for department
                this.Department = dept;
            } //end setter Department

            public String getDepartment() { //getter for department
                return Department;
            } //end getter Department
//calculate individual product inventory value

            public double getInventoryStockValue() {
                return UnitsStock * UnitPrice;
            }//end calculate individual product inventory value
//calculate total inventory value

            public double calculateInventory() {
                return UnitPrice * UnitsStock;
            }//end calculate total inventory value
///end getter and setter methods for Mobilephone
        } //end class Mobilephone

}

check it once and let me know the status

happy coding

@OP : bguild points out the core of your problem, unless you solve that , nothings gonna work out..
also , another part you might wish to take notice of is your use of the this keyword.

public void setDepartment (String dept) { //setter for department
    this.Department = dept;

you dont need to use this here , as the name of the argument passed is different to the name of the instance variable. if they were same , this would have been needed, but since thats not the case , its reduntant to use this here.

ps : a personal opinion : comments are powerful , and is a good practice to follow , however too much of a good thing isnt necessarily better. putting comments on almost every line makes the code look cluttered up. keep 'em where it impacts the most.

@radhakrishna.p: sure you can create an inner class like that.

... just shows why it's a good idea to compile (and even test!) any code before you post it here ... nothing gets past the eagle eyes ... makes you look a bit silly when you tell a beginner "do it like this" where "this" doesn't even compile :)

Thanks guys,
I knew posting here was a good Idea. I figured it was beacuse I told the program to do nothing as a program only does what you tell it, I just didn't know how I told it to do nothing. Makes sense now. I do not like java as much as C++ but it is the prefered for many mobile companies. Suppose we should look out for ceylon now.

please mark this threead as solved if you got your answer

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