Thread: A Loop statement and a switch statement issue

I was given the following code by my prof.

public static void main(String[] args) {
 
        Customer customer;
        Transaction transaction;
        double withdrawalAmount = 0;
 
        boolean finished = false;
 
        while (finished == false)
        {
            // Menu Display and Get user input
            int inputInt = 0;
            while (inputInt == 0)
            {
                inputInt = displayMenuAndGetInput();
 
                        // if the input is out of range
                        if ((inputInt < 1) || (inputInt > 8))
                        {
                                System.out.println("\nThe input is out of range!");
                                System.out.println();
                                inputInt = 0;
                        }
                } //end while
 
                // switch to correspondence function
                switch (inputInt)
 
                {
                    case 1:
                        customer = createPersonalCustomer();
                        System.out.println("\nThe Personal customer has been created: \n" + newPC.toString());
                        customers.add(customer);
                        break;
                    case 2:
                        customer = createCommercialCustomer();
                        System.out.println("\nThe Commercial customer has been created: \n" + newCC.toString());
                        customers.add(customer);
                        break;
                    case 3:
                        transaction = recordTransaction();
                        if(transaction != null)
                            System.out.println("\nThe Transaction has been created: \n" + trans.toString());
                        else
                            System.out.println("\nThe ID could not be found.");
                        break;
                    case 4:
                        withdrawalAmount = makeWithdrawal();
                        if(withdrawalAmount > 0)
                            System.out.println("\nAmount withdrawn from this account: " + moneyFormat.format(acct.getMakeWithdrawal()) + "\n");
                        else
                            System.out.println("\nThe ID could not be found.");
                        break;
                    case 5:
                        displayCustomer();
                        break;
                    case 6:
                        displayCustomerSummary();
                        break;
                    case 7:
                        displayGrandSummary();
                        break;
                    case 8:
                        // exit
                        finished = true;
                        break;
                    default:
                        System.out.println("Invalid Input!");
 
                        break;
                } // end switch
        } // end while
 
    }

I am supposed take the following code

 // Create a new Transaction
    public static Transaction recordTransaction(){
 
    	}

and make a loop that works in the following scenario:

the customer id is entered, and if the customer id is not matched in the array, the error read out in case 3 is generated and the main menu is displayed. If the customer id is valid, the user enters the input info below.

Below is my code

public static Transaction recordTransaction(){
 
System.out.println("Enter the customer ID to create the transaction > ");
    	newC.customerID = scan.nextLong();
 
    	for(int i = 0; i < customers.size(); i++) {
			if(customers.get(i).getCustomerID() == newC.getCustomerID())  {
 
				System.out.println("\nEnter the weight of gold > ");
			    	Transaction.goldWt = scan.nextDouble();
 
			    	System.out.println("\nEnter the weight of platinum > ");
			    	Transaction.platinumWt = scan.nextDouble();
 
			    	System.out.println("\nEnter the weight of silver > ");
			    	Transaction.silverWt = scan.nextDouble();
					}
    		}
				return null; 
    }

newC refers to the Customer object I created.

Anywho, I've run this a number of ways and either my code will accept an invalid and valid customer ID, or it will not accept an invalid or valid customer id.
I know I am probably overlooking something and that is why I am desperately requesting the help of the forum. I have OCD tendencies when it comes to programming and this is my first intro java class so I am not well versed in the language. I have been stuck on this issue for the last two days. Please help.

Originally Posted by Norm

Is there a need to create the newC object? No, I do not think there is a need to create the newC object.Can the code use a local variable to hold the data read from the Scanner object?Yes, I can create a local variable to hold the information from the scanner.

The method is supposed to return a Transaction object. It should ask the user for all the data needed to create a Transaction object, then call the Transaction class's constructor using a new statement and return that newly created object to the caller.

This is the part that is tripping me up. In addition I have the following helper method. Could I use it in this situation?

 // Helper method to determine if a customer exists
    public static Customer findCustomer(long customerID){
    	for (Customer c : customers) {
    		if (c.getCustomerID() == customerID)
 
    			return c;
    	}
    	return null;
    }

thank you for your help...it is really appreciated...sorry, I am having a difficult time understanding.

The problem that i am trying to solve in this situation is the following:
the customer id is entered, and if the customer id is not matched in the array, the error read out in case 3 is generated and the main menu is displayed. If the customer id is valid, the user enters additional information. the problem I am running into is with the Transaction recordTransaction();

 public static Transaction recordTransaction(){
 
    	System.out.println("Enter the customer ID to create the transaction > ");
    	long customerID = scan.nextLong();
 
    	for (Customer c : customers) {
    		if (c.getCustomerID() == customerID) {
    			if (trans != null) {
 
    			System.out.println("\nEnter the weight of gold > ");
    			Transaction.goldWt = scan.nextDouble();
 
    			System.out.println("\nEnter the weight of platinum > ");
    			Transaction.platinumWt = scan.nextDouble();
 
    			System.out.println("\nEnter the weight of silver > ");
    			Transaction.silverWt = scan.nextDouble();
    			}
    		}
    	}
		return null;
    }

now every entry I submit returns customerID not found.

ok if I remove the if (trans != null) error

 public static Transaction recordTransaction(){
 
    	System.out.println("Enter the customer ID to create the transaction > ");
 
    	long customerID = scan.nextLong();
 
    	for (Customer c : customers) {
 
    		if (c.getCustomerID() == customerID) {
 
    			Transaction trans = new Transaction();
 
    			System.out.println("\nEnter the weight of gold > ");
    			trans.goldWt = scan.nextDouble();
 
    			System.out.println("\nEnter the weight of platinum > ");
    			trans.platinumWt = scan.nextDouble();
 
    			System.out.println("\nEnter the weight of silver > ");
    			trans.silverWt = scan.nextDouble();
 
    			return trans;
    			}
    		}
    	return null;
    }

I still either get all valid responses or all invalid responses.

So the following is correct because account 123 does not exist.

*** ***
*** Welcome to Cash for Metals Calculator!!! ***
*** ***
1. Create Personal Customer
2. Create Commercial Customer
3. Record Transaction
4. Make Withdrawal
5. Display Customer
6. Display Customer Summary
7. Display Grand Summary
8. Exit

Please input your choice (1-8): 3
Enter the customer ID to create the transaction >
123

The ID could not be found.

*** ***
*** Welcome to Cash for Metals Calculator!!! ***
*** ***
1. Create Personal Customer
2. Create Commercial Customer
3. Record Transaction
4. Make Withdrawal
5. Display Customer
6. Display Customer Summary
7. Display Grand Summary
8. Exit

Please input your choice (1-8):

++++++++++++++++++++++++++++++++++++++++++++++++++ +++++++++++++
the following is not correct because the customer for 1362672823 was just entered in the same session.

*** ***
*** Welcome to Cash for Metals Calculator!!! ***
*** ***
1. Create Personal Customer
2. Create Commercial Customer
3. Record Transaction
4. Make Withdrawal
5. Display Customer
6. Display Customer Summary
7. Display Grand Summary
8. Exit

Please input your choice (1-8): 3
Enter the customer ID to create the transaction >
1362672823

The ID could not be found.

*** ***
*** Welcome to Cash for Metals Calculator!!! ***
*** ***
1. Create Personal Customer
2. Create Commercial Customer
3. Record Transaction
4. Make Withdrawal
5. Display Customer
6. Display Customer Summary
7. Display Grand Summary
8. Exit

Please input your choice (1-8):

Here posting the entire process:


*** ***
*** Welcome to Cash for Metals Calculator!!! ***
*** ***
1. Create Personal Customer
2. Create Commercial Customer
3. Record Transaction
4. Make Withdrawal
5. Display Customer
6. Display Customer Summary
7. Display Grand Summary
8. Exit

Please input your choice (1-8): 1
Enter the customer name >
John Doe

Enter the customer address >
123 Grove Ave

Enter the customer home phone >
123-456-7890

Enter the customer work phone >
132-456-7890

The Personal customer has been created:
Customer Name: John Doe
Customer ID: 1362673167
Customer Address: 123 Grove Ave

Account Number: 1362673167
Balance: $0.00
Interest Rate: 0.03
Date Opened: Thu Mar 07 08:19:10 PST 2013

Home Phone: 123-456-7890
Work Phone: 132-456-7890

*** ***
*** Welcome to Cash for Metals Calculator!!! ***
*** ***
1. Create Personal Customer
2. Create Commercial Customer
3. Record Transaction
4. Make Withdrawal
5. Display Customer
6. Display Customer Summary
7. Display Grand Summary
8. Exit

Please input your choice (1-8): 3
Enter the customer ID to create the transaction >
123

The ID could not be found.

*** ***
*** Welcome to Cash for Metals Calculator!!! ***
*** ***
1. Create Personal Customer
2. Create Commercial Customer
3. Record Transaction
4. Make Withdrawal
5. Display Customer
6. Display Customer Summary
7. Display Grand Summary
8. Exit

Please input your choice (1-8): 3
Enter the customer ID to create the transaction >
1362673167

The ID could not be found.

*** ***
*** Welcome to Cash for Metals Calculator!!! ***
*** ***
1. Create Personal Customer
2. Create Commercial Customer
3. Record Transaction
4. Make Withdrawal
5. Display Customer
6. Display Customer Summary
7. Display Grand Summary
8. Exit

Please input your choice (1-8):

Okay, I discovered that the issue is with the following:

we are asked to use the following code to generate a unique customerID number.

 long customerID = Calendar.getInstance().getTimeInMillis()/1000;

this does not allow me to lookup the customerID.

However, if I set the customerID = 4 (or any other number), the programs works like it is supposed to; it brings up the right information.

How can I fix the issue with the random customerID number in order to get it to work as intended?