Exercise 3 in Java Produce 3 of 9 in Java Exercise 3

Exercise 3 using swing tomake barcode 39 on web,windows application How to Use Visual Studio 2010 Java can perform inte barcode 3/9 for Java rnationalization. Remove (or comment out) the applyPattern statement in

Does it still use the standard German format . 10.4 The Shopping Cart A shopping cart in ou Code 39 Full ASCII for Java r case is a list of books and a respective quantity (always 1). If necessary, customers must log in after registering before they may use the shopping cart. Once the order process is complete, the shopping cart is deleted.

For us, the shop ends at this point; we have removed the shopkeeper from the process!. 10 . 10.4.1 Login The shopping cart is only accessible to registered customers, so we need a link to the login form. If an incorrect e-mail and password combination is supplied, an error message is displayed; otherwise we greet the customer by name. It makes sense to use the now-familiar form procedure.

We already have a customer bean, forms, and Action classes. As we will see shortly, using them as they are results in some problems (see Listing 10.12).

First, we have the HTML form as shown in Listing 10.10, which contains some new Struts functionality. Listing 10.

10: view/Login.jsp. <%@ taglib uri="/W spring framework Code39 EB-INF/struts-bean.tld" prefix="bean" %> <%@ taglib uri="/WEB-INF/struts-html.tld" prefix="html" %> <%@page import="tools.

*, customer.*"%> <% java.util.

logging.Logger logger = LoggerInitiator.getLogger(); logger.

info("Login.jsp"); %> <bean:message key="login.title"/> <html:form action="/login" focus="mail"> <bean:message key="general.

mail"/> <html:text property="mail" size="20" /> <br /> <bean:message key="general.password"/> <html:text property="password" size="20" /> <br /> <html:submit value="Enter" /> </html:form> <br /> <a href="<%=response.encodeURL(".

./CustomerCreation.jsp")%>"> <bean:message key="link.

createcustomer" /> </a>. The form appears just as we are used to, the difference being that we don"t need to build our own bean. Instead, we will be using special notation in struts-config.xml: Specialized subclass of ActionForm that allows the creation of form beans with dynamic sets of properties, without requiring the developer to create a Java class for each type of form bean.

Struts API. Putting It All Together Listing 10.11: DynaAction in struts-config.xml <form-beans> . j2se barcode 3 of 9 . .

<form-bean name="loginForm" type="org.apache.struts.

action.DynaActionForm"> <form-property name="mail" type="java.lang.

String" /> <form-property name="password" type="java.lang.String"/> </form-bean> </form-beans> .

. . <global-forwards> .

. . <forward name="customerCreated" path="/view/CustomerView.

jsp"/> <forward name="loginSuccess" path="/view/LoginView.jsp"/> </global-forwards> <action-mappings> . .

. <action path="/login" type="customer.LoginAction" name="loginForm" scope="request" input="/CusomerLogin.

jsp"> </action> </action-mappings>. The </form-bean> ; entry now contains two <form-property> elements. The values used in the form on the JSP are associated with a data type, and Struts generates a bean class for us automatically. The <global-forward> and <action-mapping> are the same as usual.

As far as the naming is concerned, loginSuccess has been used instead of loginCreated, but this is simply a matter of personal preference. We don"t need to write a class.

This relieves us from some work, but it means we don"t have the validate() method. This is not a problem here, because we are going to test the entries against the database anyway. We still don"t have the Action class.

Here we encounter a problem: Listing 10.12: LoginAction.execute().

public ActionForward jvm barcode 3/9 execute(ActionMapping mapping, ActionForm form, HttpServletRequest req, HttpServletResponse res) throws Exception { DynaActionForm df = (DynaActionForm)form; String mail = (String)df.get("mail");. 10 . String password = (St Code 39 Full ASCII for Java ring)df.get("password"); logger.debug("mail=" + mail + " / pass=" + password); Customer k = new Customer(mail, password); return mapping.

findForward("loginSuccess"); }. We can determine and process the input data from the request, but we have to check the values against the database and load the customer data completely. The problem is that the database functionality is in, whereas we need it in Customer.

java now. At the time, that was the optimal solution, but now we are faced with the choice of either shifting the code to the Customer class, or creating a new class of its own. We now create shop8 from shop7.

. Exercise 4 1. Before you read fu rther, think about how you would solve the problem mentioned above. Then implement it.

There is no right or wrong answer for this; it"s all down to how the application is going to be used further. For each of the possibilities mentioned, think of how you"d justify it to your boss. One choice would be to place the SQL statements in Customer.

java. The LoginAction.execute() method without SQL then becomes: Listing 10.

13: customer.LoginAction.execute() without SQL.

public ActionForward applet ANSI/AIM Code 39 execute(ActionMapping mapping, ActionForm form, HttpServletRequest req, HttpServletResponse res) throws Exception { CustomerForm kf = (CustomerForm)form; Customer k = kf.getCustomer(); k.create(); HttpSession session = req.

getSession(true); session.setAttribute("customer", k); return mapping.findForward("customerCreated"); }.

The database-specific methods in essentially correspond to those from

2. What happens if incorrect details are provided on login How could you improve this to be more customer-friendly 3. Consider what is required to allow customers to make changes to their shopping cart, such as increasing or decreasing the number of books.

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