Problem with createCustomerBean code

>                   if ("susername" != "Customer.username")

should use equals() to compare string


                  if (!"susername".equals("Customer.username"))

This is strange if statement:

if ("susername" != "Customer.username")

You probably don't want quotes

    if (!susername.equals("Customer.username"))

At least in one place you done' t want quotes
because this:

    if (!"susername".equals("Customer.username"))

will always be true.

and if think you actually mean to do this:

                  if (!susername.equals(Customer.getUsername()))

But that won't work as you haven't assigned customer to anything

To check if a customer already exists you are going to need to query the database

Or alternatively you can set unique constraint on username in the database table (probably a good idea anyway)
and then check the numbert of inserted records:

int inserted = stmt.executeUpdate(strSQL);
if(inserted != 1) {
Syatem.out.println("Not unique username or another error while inserting user record into database");
}

Sorry -- didn't see the replies -- I cancel my request to cancel -- someone has already seen my error and I will continue to accept solutions.
Thank you for the ones so far!
Bette

OK, I ran with the new code and it is not letting me create a new customer -- it is reverting to the exception that username doesn't exist when I put a new user into my argument. I guess I don't know what to enter in the run configuration arguments to let the program know that I am adding a record -- not trying to pull out a pre-existing record. Sorry to be so dense -- never used Beans before. I am using Eclipse.
Bette

Maybe you want to post a new code you are running now and also
post the exception stack trace

I get this code when I type in a new username -- which is what I should get if I was pulling out a name already in the datatbase. java.lang.Exception: Invalid username: woaJessie
      at bettelamore.CustomerBean.<init>(CustomerBean.java:87)
      at bettelamore.CustomerBean.main(CustomerBean.java:305)

so that part is OK -- what I don't know how to do is enter a new username by using the run configuration arguments??
Thanks for your prompt reply!!

revised code:

package bettelamore;

import java.sql.*;
import java.util.*;

/**
 * <p>
 * This is the Java bean used to get and display information about customers for
 * our web based store.
 * 
 * @see DBBeanBase
 */
public class CustomerBean extends DBBeanBase
{
	/**
	 * <p>
	 * Default constructor, creates an empty {@link ItemBean}.
	 */
	public CustomerBean()
	{
		super();
	}

	/**
	 * <p>
	 * Copy constructor. This constructor creates a {@link CustomerBean} object
	 * that is initially populated with a copy of the {@link Map} specified as a
	 * parameter to this constructor. All {@link java.util.Map Maps} should
	 * implement a copy constructor.
	 * 
	 * @param copyThisMap
	 *            the {@link Map} used to initialize this {@link CustomerBean}
	 *            object.
	 */
	public CustomerBean(Map copyThisMap)
	{
		super(copyThisMap);
	}

	/**
	 * <p>
	 * This constructor creates an {@link CustomerBean} object and populates it
	 * with the fields in a {@link java.sql.ResultSet}.
	 * 
	 * @param rs
	 *            The {@link java.sql.ResultSet} object used to populate this
	 *            class with information about an item.
	 * 
	 * @throws java.sql.SQLException
	 *             if there is an error iterating the {@link java.sql.ResultSet}
	 *             .
	 */
	protected CustomerBean(ResultSet rs) throws SQLException
	{
		super(rs);
	}

	/**
	 * <p>
	 * This constructor creates an {@link CustomerBean} object associated with
	 * the specified username. If there is no record in the data source with the
	 * specified username, an exception is thrown.
	 * 
	 * @param connection
	 *            The {@link java.sql.Connection} object used to execute the
	 *            select statement that will retrieve the item information.
	 * @param susername
	 *            specifies the username used to populate this object.
	 * 
	 * @throws java.sql.SQLException
	 *             if there is an error selecting the customer information.
	 * @throws java.lang.Exception
	 *             if the username is invalid.
	 */
	public CustomerBean(Connection connection, String susername) throws SQLException, Exception
	{
		super();
		String strSQL = "SELECT * FROM customer WHERE username = '" + susername + "'";
		Statement statement = connection.createStatement();
		ResultSet rs = statement.executeQuery(strSQL);
		if (rs.next())
		{
			populateFromResultSet(rs);
		}
		else
		{
			throw new Exception("Invalid username: " + susername);
		}
	}

	/**
	 * <p>
	 * This method returns the username.
	 * 
	 * @return the username.
	 */
	public String getUsername()
	{
		return get("username").toString();
	}

	/**
	 * <p>
	 * This method returns the name of the customer's password.
	 * 
	 * @return the name of the customer's password.
	 */
	public String getPassword()
	{
		return get("PASSWORD").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's address.
	 * 
	 * @return the customer's address.
	 */
	public String getAddress()
	{
		return get("ADDRESS").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's city.
	 * 
	 * @return the customer's city.
	 */
	public String getCity()
	{
		return get("CITY").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's state.
	 * 
	 * @return the customer's state.
	 */
	public String getState()
	{
		return get("STATE").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's zipcode.
	 * 
	 * @return the customer's zipcode.
	 */
	public String getZip()
	{
		return get("ZIP").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's email address.
	 * 
	 * @return the customer's email address.
	 */
	public String getEmail()
	{
		return get("ADDRESS").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's phone number.
	 * 
	 * @return the customer's phone number.
	 */
	public String getPhone()
	{
		return get("PHONE").toString();
	}

	/**
	 * <p>
	 * This method returns a textual representation of this {@link CustomerBean}.
	 * 
	 * @return a textual representation of this {@link CustomerBean}.
	 */
	public String toString()
	{
		StringBuffer sb = new StringBuffer();
		sb.append("username: " + getUsername() + "\n");
		sb.append("Password: " + getPassword() + "\n");
		sb.append("Address: " + getAddress() + "\n");
		sb.append("City: " + getCity().toString() + "\n");
		sb.append("State: " + getState().toString() + "\n");
		sb.append("Zip: " + getZip().toString() + "\n");
		sb.append("Phone: " + getPhone().toString() + "\n");
		sb.append("Email: " + getEmail().toString() + "\n");
		return sb.toString();
	}

	/**
	 * <p>
	 * This method returns a {@link java.util.Collection} of all of the
	 * customers in the data source. This is really the store's customer base.
	 * 
	 * @param connection
	 *            The {@link java.sql.Connection} object used to execute the
	 *            select statement that will retrieve the customers.
	 * 
	 * @return a {@link java.util.Collection} of all of the customers in the
	 *         data source.
	 * 
	 * @throws java.sql.SQLException
	 *             if there is an error selecting the customer.
	 */
	public static Collection getAllCustomers(Connection connection) throws SQLException
	{
		Collection col = new ArrayList();

		String strSQL = "SELECT * FROM customer";
		Statement statement = connection.createStatement();
		ResultSet rs = statement.executeQuery(strSQL);
		while (rs.next())
		{
			col.add(new CustomerBean(rs));
		}
		return col;
	}

	public static CustomerBean createCustomer(Connection connection,
    		String username,
    		String password,
    		String address,
    		String city,
    		String state,
    		String zip,
    		String email,
    		String phone,
    		String creditcard) throws SQLException, Exception
    {
			
    		Statement stmt = connection.createStatement();
    		String strSQL = null;
			int inserted = stmt.executeUpdate(strSQL);
			if(inserted != 1) 
			{
				System.out.println("Not unique username or another error while inserting user record into database");
	    		strSQL = "INSERT INTO CUSTOMER (username, password, address, city, state, zip, email, phone, creditcard) " +
	    			"VALUES (" + username + ", " + password + ", " + address + ", " + city + ", " + state + ", " + zip + ", " +
	    					email + ", " + phone + ", " + creditcard + ")";
	
	    		stmt.executeUpdate(strSQL);
	    		return new CustomerBean(connection, username);
	    	}	
			else
			{
				return null;
			}
    	// check to see if a customer already exists with this username,
    	// if they do, return null, otherwise add the new customer and return
    	// a new CustomerBean for the new customer... }
		
    }

	/**
	 * <p>
	 * Test method used to test this class. This method creates an CustomerBean
	 * object using the specified DBURL and username. The contents of the
	 * CustomerBean are printed to the console. In addition, this method gets a
	 * {@link java.util.Collection} of all of the customers in the data source
	 * and prints them on the console.
	 * 
	 * <p>
	 * This test method assumes that the database is a MySQL database that
	 * contains an 'user1' account with a password 'user1'.
	 * 
	 * <pre>
	 *      usage: java DBBean [DBURL] [username]
	 * </pre>
	 * 
	 * @param args
	 *            an array of command line arguments. This test method takes two
	 *            parameters, one that specifies the DBURL and the other
	 *            specifies the username.
	 */

	public static void main(String[] args)
	{
		Connection connection = null;
		try
		{
			if (args.length != 2)
			{
				System.out.println("usage: java CustomerBean [DBURL] [username]");
				System.out.println("Example DBURL: jdbc:mysql://localhost:3306/WebStore");
				System.exit(0);
			}

			String strDBDriver = "com.mysql.jdbc.Driver";
			String strDBURL = args[0];
			String strDBUSER = "user1";
			String strDBPWD = "user1";

			Class.forName(strDBDriver);
			connection = DriverManager.getConnection(strDBURL, strDBUSER, strDBPWD);

			DBBeanBase customerBean = new CustomerBean(connection, args[1]);
			System.out.println("A Customer:\n" + customerBean);

			System.out.println("All Customers:\n" + CustomerBean.getAllCustomers(connection));
		}
		catch (Exception e)
		{
			e.printStackTrace();
		}
		finally
		{
			try
			{
				connection.close();
			}
			catch (Exception e)
			{
			}
		}
	}
}

Select allOpen in new window

But if you have new username rs.next() will be false
and it 'll throw Exception according to your code

throw new Exception("Invalid username: " + susername);

I added the code and now I am getting an exception if I add a username that is already in database. I am realizing I have 2 scenarios that are diametrically opposing and if I correct one situation, the other goes bad. How do I test for the pulling out a preexisting name and then test for adding a new user?

package bettelamore;

import java.sql.*;
import java.util.*;

/**
 * <p>
 * This is the Java bean used to get and display information about customers for
 * our web based store.
 * 
 * @see DBBeanBase
 */
public class CustomerBean extends DBBeanBase
{
	/**
	 * <p>
	 * Default constructor, creates an empty {@link ItemBean}.
	 */
	public CustomerBean()
	{
		super();
	}

	/**
	 * <p>
	 * Copy constructor. This constructor creates a {@link CustomerBean} object
	 * that is initially populated with a copy of the {@link Map} specified as a
	 * parameter to this constructor. All {@link java.util.Map Maps} should
	 * implement a copy constructor.
	 * 
	 * @param copyThisMap
	 *            the {@link Map} used to initialize this {@link CustomerBean}
	 *            object.
	 */
	public CustomerBean(Map copyThisMap)
	{
		super(copyThisMap);
	}

	/**
	 * <p>
	 * This constructor creates an {@link CustomerBean} object and populates it
	 * with the fields in a {@link java.sql.ResultSet}.
	 * 
	 * @param rs
	 *            The {@link java.sql.ResultSet} object used to populate this
	 *            class with information about an item.
	 * 
	 * @throws java.sql.SQLException
	 *             if there is an error iterating the {@link java.sql.ResultSet}
	 *             .
	 */
	protected CustomerBean(ResultSet rs) throws SQLException
	{
		super(rs);
	}

	/**
	 * <p>
	 * This constructor creates an {@link CustomerBean} object associated with
	 * the specified username. If there is no record in the data source with the
	 * specified username, an exception is thrown.
	 * 
	 * @param connection
	 *            The {@link java.sql.Connection} object used to execute the
	 *            select statement that will retrieve the item information.
	 * @param susername
	 *            specifies the username used to populate this object.
	 * 
	 * @throws java.sql.SQLException
	 *             if there is an error selecting the customer information.
	 * @throws java.lang.Exception
	 *             if the username is invalid.
	 */

	public CustomerBean(Connection connection, String susername) throws SQLException, Exception
	{
		super();
		String strSQL = "SELECT * FROM customer WHERE username = '" + susername + "'";
		Statement statement = connection.createStatement();
		ResultSet rs = statement.executeQuery(strSQL);
		boolean found = false;
		while (rs.next())
		{
			found = true;
		}
		if (found)
		{
			
			throw new Exception("Invalid username: " + susername);
			// do somthing if username already exists
		}
		else
		{
			// do something if a new username
			populateFromResultSet(rs);
		}
	}

	/**
	 * <p>
	 * This method returns the username.
	 * 
	 * @return the username.
	 */
	public String getUsername()
	{
		return get("username").toString();
	}

	/**
	 * <p>
	 * This method returns the name of the customer's password.
	 * 
	 * @return the name of the customer's password.
	 */
	public String getPassword()
	{
		return get("PASSWORD").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's address.
	 * 
	 * @return the customer's address.
	 */
	public String getAddress()
	{
		return get("ADDRESS").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's city.
	 * 
	 * @return the customer's city.
	 */
	public String getCity()
	{
		return get("CITY").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's state.
	 * 
	 * @return the customer's state.
	 */
	public String getState()
	{
		return get("STATE").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's zipcode.
	 * 
	 * @return the customer's zipcode.
	 */
	public String getZip()
	{
		return get("ZIP").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's email address.
	 * 
	 * @return the customer's email address.
	 */
	public String getEmail()
	{
		return get("ADDRESS").toString();
	}

	/**
	 * <p>
	 * This method returns the customer's phone number.
	 * 
	 * @return the customer's phone number.
	 */
	public String getPhone()
	{
		return get("PHONE").toString();
	}

	/**
	 * <p>
	 * This method returns a textual representation of this {@link CustomerBean}.
	 * 
	 * @return a textual representation of this {@link CustomerBean}.
	 */
	public String toString()
	{
		StringBuffer sb = new StringBuffer();
		sb.append("username: " + getUsername() + "\n");
		sb.append("Password: " + getPassword() + "\n");
		sb.append("Address: " + getAddress() + "\n");
		sb.append("City: " + getCity().toString() + "\n");
		sb.append("State: " + getState().toString() + "\n");
		sb.append("Zip: " + getZip().toString() + "\n");
		sb.append("Phone: " + getPhone().toString() + "\n");
		sb.append("Email: " + getEmail().toString() + "\n");
		return sb.toString();
	}

	/**
	 * <p>
	 * This method returns a {@link java.util.Collection} of all of the
	 * customers in the data source. This is really the store's customer base.
	 * 
	 * @param connection
	 *            The {@link java.sql.Connection} object used to execute the
	 *            select statement that will retrieve the customers.
	 * 
	 * @return a {@link java.util.Collection} of all of the customers in the
	 *         data source.
	 * 
	 * @throws java.sql.SQLException
	 *             if there is an error selecting the customer.
	 */
	public static Collection getAllCustomers(Connection connection) throws SQLException
	{
		Collection col = new ArrayList();

		String strSQL = "SELECT * FROM customer";
		Statement statement = connection.createStatement();
		ResultSet rs = statement.executeQuery(strSQL);
		while (rs.next())
		{
			col.add(new CustomerBean(rs));
		}
		return col;
	}

	public static CustomerBean createCustomer(Connection connection, String username, String password, String address, String city, String state, String zip, String email, String phone, String creditcard) throws SQLException, Exception
	{

		Statement stmt = connection.createStatement();
		String strSQL = null;
		int inserted = stmt.executeUpdate(strSQL);
		if (inserted != 1)
		{
			System.out.println("Not unique username or another error while inserting user record into database");
			strSQL = "INSERT INTO CUSTOMER (username, password, address, city, state, zip, email, phone, creditcard) " + "VALUES (" + username + ", " + password + ", " + address + ", " + city + ", " + state + ", " + zip + ", " + email + ", " + phone + ", " + creditcard + ")";

			stmt.executeUpdate(strSQL);
			return new CustomerBean(connection, username);
		}
		else
		{
			return null;
		}
		// check to see if a customer already exists with this username,
		// if they do, return null, otherwise add the new customer and return
		// a new CustomerBean for the new customer... }

	}

	/**
	 * <p>
	 * Test method used to test this class. This method creates an CustomerBean
	 * object using the specified DBURL and username. The contents of the
	 * CustomerBean are printed to the console. In addition, this method gets a
	 * {@link java.util.Collection} of all of the customers in the data source
	 * and prints them on the console.
	 * 
	 * <p>
	 * This test method assumes that the database is a MySQL database that
	 * contains an 'user1' account with a password 'user1'.
	 * 
	 * <pre>
	 *      usage: java DBBean [DBURL] [username]
	 * </pre>
	 * 
	 * @param args
	 *            an array of command line arguments. This test method takes two
	 *            parameters, one that specifies the DBURL and the other
	 *            specifies the username.
	 */

	public static void main(String[] args)
	{
		Connection connection = null;
		try
		{
			if (args.length != 2)
			{
				System.out.println("usage: java CustomerBean [DBURL] [username]");
				System.out.println("Example DBURL: jdbc:mysql://localhost:3306/WebStore");
				System.exit(0);
			}

			String strDBDriver = "com.mysql.jdbc.Driver";
			String strDBURL = args[0];
			String strDBUSER = "user1";
			String strDBPWD = "user1";

			Class.forName(strDBDriver);
			connection = DriverManager.getConnection(strDBURL, strDBUSER, strDBPWD);

			DBBeanBase customerBean = new CustomerBean(connection, args[1]);
			System.out.println("A Customer:\n" + customerBean);

			System.out.println("All Customers:\n" + CustomerBean.getAllCustomers(connection));
		}
		catch (Exception e)
		{
			e.printStackTrace();
		}
		finally
		{
			try
			{
				connection.close();
			}
			catch (Exception e)
			{
			}
		}
	}
}

Select allOpen in new window

But that's what you wanted - to throw exception
if the username  already exists in the databse - isn't that waht you need?

Yan really worked hard on this one. My mouse slipped and clicked on the last post not being helpful but that was an error. I beleive you've solved my problem -- it is just that I am having a hard time testing the additional code in Eclipse.
Thank you so much for your time.
Bette

Oh yan -- there are 2 parts to this program -- one is to extract info already in database, and one is to add info -- new user-- to database. I am having a tough time testing for both. Never had to do that before and I am using Eclipse Run Configuration with args for testing.

Well, test them stepwise - one part, another part,
I don't think there is anything  too complicated about it -  just like any other debugging.

I guess I was trying to figure out a way to test both scenarious at the same time -- working to hard on all this code for my store that I am a little brain dead at present :-)
Thanks for all your help!
Bette