Download ppt

1 26 Web Applications: Part 1  2007 Pearson Education, Inc. All rights reserved. 2 If any man will draw up his case, and put his name at the foot of the first page, I will give him an immediate reply. Where he compels me to turn over the sheet, he must wait my leisure. —Lord Sandwich Rule One: Our client is always right Rule Two: If you think our client is wrong, see Rule One. —Anonymous  2007 Pearson Education, Inc. All rights reserved. 3 A fair question should be followed by a deed in silence. —Dante Alighieri You will come here and get books that will open your eyes, and your ears, and your curiosity, and turn you inside out or outside in. —Ralph Waldo Emerson  2007 Pearson Education, Inc. All rights reserved. 4 OBJECTIVES In this chapter you will learn:  Web application development using Java Technologies and Java Studio Creator 2.0.  To create JavaServer Pages with JavaServer Faces components.  To create web applications consisting of multiple pages.  To validate user input on a web page.  To maintain state information about a user with session tracking and cookies.  2007 Pearson Education, Inc. All rights reserved. 5 26.1 26.2 26.3 26.4 26.5 Introduction Simple HTTP Transactions Multitier Application Architecture Java Web Technologies 26.4.1 Servlets 26.4.2 JavaServer Pages 26.4.3 JavaServer Faces 26.4.4 Web Technologies in Java Studio Creator 2 Creating and Running a Simple Application in Java Studio Creator 2 26.5.1 Examining a JSP File 26.5.2 Examining a Page Bean File 26.5.3 Event-Processing Life Cycle 26.5.4 Relationship Between the JSP and Page Bean Files  2007 Pearson Education, Inc. All rights reserved. 6 26.6 26.7 26.8 26.9 26.5.5 Examining the XHTML Generated by a Java Web Application 26.5.6 Building a Web Application in Java Studio Creator 2 JSF Components 26.6.1 Text and Graphics Components 26.6.2 Validation Using Validator Components and Custom Validators Session Tracking 26.7.1 Cookies 26.7.2 Session Tracking with the SessionBean Object Wrap-Up Web Resources  2007 Pearson Education, Inc. All rights reserved. 7 26.1 Introduction  Web-based applications create web content for web browser clients  AJAX—provides interactivity and responsiveness users typically expect of desktop applications  1992-2007 Pearson Education, Inc. All rights reserved. 8 26.2 Simple HTTP Transactions  Hypertext Transfer Protocol (HTTP) – set of methods and headers that allow clients and servers to interact and exchange information  Simple web page – Typically an XHTML document – Contains markup that describes to a web browser how to display the document  Hypertext data (hyperlinks) – link to different pages or to other parts of the same page when the user clicks the link  1992-2007 Pearson Education, Inc. All rights reserved. 9 26.2 Simple HTTP Transactions  URIs (Uniform Resource Identifiers) – Identify data on the Internet – Those that specify the locations of documents are called URLs (Uniform Resource Locators)  Common URLs refer to – Files – Directories – Objects that perform complex tasks  URL directs a browser to the resource (hosted on a web server) that the user wishes to access  1992-2007 Pearson Education, Inc. All rights reserved. 10 26.2 Simple HTTP Transactions  HTTP GET method indicates that the client wishes to obtain a resource from the server  HTTP headers provide information about the data sent to a client, such as the MIME type  Multipurpose Internet Mail Extensions (MIME) – Internet standard that specifies data formats so that programs can interpret data correctly  1992-2007 Pearson Education, Inc. All rights reserved. 11 Fig. 26.1 | Client interacting with web server. Step 1: The GET request.  2007 Pearson Education, Inc. All rights reserved. 12 Fig. 26.2 | Client interacting with web server. Step 2: The HTTP response.  2007 Pearson Education, Inc. All rights reserved. 13 26.3 Multitier Application Architecture  Web-based applications are multitier (or n-tier) applications that divide functionality into separate tiers that typically reside on separate computers  Bottom tier – Also called the data tier or the information tier – Maintains the application’s data – Typically stores data in a relational database management system (RDBMS)  Middle tier – Implements business logic, controller logic and presentation logic – Acts as an intermediary between data in the information tier and the application’s clients – Controller logic processes client requests and retrieves data from the database – Presentation logic processes data from the information tier and presents the content to the client  1992-2007 Pearson Education, Inc. All rights reserved. 14 26.3 Multitier Application Architecture  Web applications typically present data to clients as XHTML documents.  Business logic in the middle tier – enforces business rules – ensures that data is reliable before the server application updates the database or presents the data to users  Business rules dictate – How clients can and cannot access application data – How applications process data  Top tier – Also called client tier – The application’s user interface, which gathers input and displays output – Users interact with the application through the user interface, typically in a web browser.  1992-2007 Pearson Education, Inc. All rights reserved. 15 26.3 Multitier Application Architecture  In response to user actions – Client tier interacts with middle tier to make requests and to retrieve data from information tier – Client tier then displays data retrieved for the user – Client tier never directly interacts with the information tier  1992-2007 Pearson Education, Inc. All rights reserved. 16 Fig. 26.3 | Three-tier architecture.  2007 Pearson Education, Inc. All rights reserved. 17 26.4 Java Web Technologies  Continually evolve to provide developers with higher levels of abstraction and greater separation of the application’s tiers  Separation makes web applications more maintainable and extensible  Java Studio Creator 2 – Drag-and-drop web-application GUI development – Business logic placed in separate Java classes  1992-2007 Pearson Education, Inc. All rights reserved. 18 26.4.1 Servlets  Use the HTTP request-response model of communication between client and server  Extend a server’s functionality by allowing the server to generate dynamic content  Servlet container executes and interacts with servlets  Packages javax.servlet and javax.servlet.http contain the servlet classes and interfaces.  1992-2007 Pearson Education, Inc. All rights reserved. 19 26.4.1 Servlets  Servlet container – Receives HTTP requests from clients – Directs each request to the appropriate servlet – Servlet processes the request and returns response to the client—typically an XHTML or XML document  Servlets implement the Servlet interface of package javax.servlet – Ensures that each servlet can execute in the framework – Declares methods used by the servlet container to manage the servlet’s life cycle  1992-2007 Pearson Education, Inc. All rights reserved. 20 26.4.1 Servlets  Servlet life cycle – Begins when the servlet container loads it into memory—usually in response to the first request for the servlet – init method - Called only once by container during a servlet’s life-cycle to initialize the servlet – service method - Called once per request Receives the request Processes it Sends a response to the client – destroy method - Called to release any resources held by the servlet when container terminates servlet  1992-2007 Pearson Education, Inc. All rights reserved. 21 26.4.2 JavaServer Pages  Extension of servlet technology  Each JSP is translated by the JSP container into a servlet  Help separate presentation from content  Help web application programmers create dynamic content – By reusing predefined components – By interacting with components using server-side scripting  1992-2007 Pearson Education, Inc. All rights reserved. 22 26.4.2 JavaServer Pages  JavaBeans and custom tag libraries encapsulate complex, dynamic functionality  Custom tag libraries – Allow Java developers to hide code for database access and other complex operations in custom tags – Enable web-page designers who are not familiar with Java to enhance web pages with powerful dynamic content and processing capabilities  The JSP classes and interfaces are located in packages javax.servlet.jsp and javax.servlet.jsp.tagext.  1992-2007 Pearson Education, Inc. All rights reserved. 23 26.4.2 JavaServer Pages  Four key components – – – – Directives Actions Scripting elements Tag libraries  Directives – – – – Messages to the JSP container Specify page settings Include content from other resources Specify custom tag libraries for use in JSPs  Actions – Encapsulate functionality in predefined tags – Often are performed based on the information sent to the server as part of a particular client request – Can create Java objects for use in JSPs  1992-2007 Pearson Education, Inc. All rights reserved. 24 26.4.2 JavaServer Pages  Scripting elements – Insert Java code that interacts with components in a JSP to perform request processing  Tag libraries – Enable programmers to create custom tags – Enable web-page designers to manipulate JSP content without prior Java knowledge  JavaServer Pages Standard Tag Library (JSTL) – Provides many common web application tasks  Static content – XHTML or XML markup – Known as fixed-template data or fixed-template text – Literal text is translated to a String literal in the servlet representation of the JSP  1992-2007 Pearson Education, Inc. All rights reserved. 25 26.4.2 JavaServer Pages  First request for a JSP – Container translates the JSP into a servlet – Servlet handles the current and future requests to the JSP  JSPs rely on the same request/response mechanism as servlets to process requests from and send responses to clients  1992-2007 Pearson Education, Inc. All rights reserved. 26 Performance Tip 26.1 Some JSP containers translate JSPs into servlets at the JSP’s deployment time (i.e., when the application is placed on a web server). This eliminates the translation overhead for the first client that requests each JSP, as the JSP will be translated before it is ever requested by a client.  2007 Pearson Education, Inc. All rights reserved. 27 26.4.3 JavaServer Faces  Web application framework – Simplifies the design of an application’s user interface – Further separates a web application’s presentation from its business logic  Framework – Simplifies application development by providing libraries and sometimes software tools to help you organize and build your applications  1992-2007 Pearson Education, Inc. All rights reserved. 28 26.4.3 JavaServer Faces  JSF custom tag libraries – Contain user interface components that simplify web-page design – Includes a set of APIs for handling component events  You design the look-and-feel of a page with JSF by adding custom tags to a JSP file and manipulating their attributes  You define the page’s behavior in a separate Java source-code file.  1992-2007 Pearson Education, Inc. All rights reserved. 29 26.4.4 Web Technologies in Java Studio Creator 2  Java Studio Creator 2 web applications – Consist of one or more JSPs built in the JavaServer Faces framework – Each has the file-name extension .jsp and contains the web page’s GUI elements  Java Studio Creator 2 allows you to – Design pages visually by dragging and dropping JSF components onto a page; – Customize a web page by editing its .jsp file manually  Every JSP file created in Java Studio Creator 2 represents a web page and has a corresponding JavaBean class called the page bean  1992-2007 Pearson Education, Inc. All rights reserved. 30 26.4.4 Web Technologies in Java Studio Creator 2  JavaBean class must have – Default (or no-argument) constructor – get and set methods for all of its properties.  page bean – – – – Defines properties for each of the page’s elements Event handlers Page life-cycle methods Other supporting code for the web application  Every web application built with Java Studio Creator 2 has a page bean, a RequestBean, a SessionBean and an ApplicationBean  1992-2007 Pearson Education, Inc. All rights reserved. 31 26.4.4 Web Technologies in Java Studio Creator 2  RequestBean – Request scope – Exists only for the duration of an HTTP request  SessionBean – Session scope – Exists throughout a user’s browsing session or until the session times out – Unique SessionBean object for each user  ApplicationBean – – – – – Application scope Shared by all instances of an application Exists as long as the application remains deployed Application-wide data storage or processing One instance exists, regardless of the number of open sessions  1992-2007 Pearson Education, Inc. All rights reserved. 32 26.5 Creating and Running a Simple Application in Java Studio Creator 2  Static Text components display text that cannot be edited by the user  1992-2007 Pearson Education, Inc. All rights reserved. 1 <?xml version = "1.0" encoding = "UTF-8"?> 2 3  4 5 6 7 8 9   <jsp:root version = "1.2" Time.jsp xmlns:f = "http://java.sun.com/jsf/core" Tag libraries available for xmlns:h = "http://java.sun.com/jsf/html" use in this web application (1 of 2 ) xmlns:jsp = "http://java.sun.com/JSP/Page" 10 11 xmlns:ui = "http://www.sun.com/web/ui"> <jsp:directive.page contentType = "text/html; charset = UTF-8" 12 13 14 pageEncoding = "UTF-8"/> <f:view> <ui:page binding = "#{Time.page}" id = "page"> 15 16 17 18 19 20 <ui:html binding = "#{Time.html}" id = "html"> <ui:head binding = "#{Time.head}" id = "head" title = "Web Time: A Simple Example"> <ui:link binding = "#{Time.link}" id = "link" 33 Outline Configure head section of web page url = "/resources/stylesheet.css"/> </ui:head>  2007 Pearson Education, Inc. All rights reserved. 21 22 23 24 25 26 <ui:meta content = "60" httpEquiv = "refresh"/> <ui:body binding = "#{Time.body}" id = "body" style = "-rave-layout: grid"> <ui:form binding = "#{Time.form}" id = "form"> <ui:staticText binding = "#{Time.timeHeader}" id = "timeHeader" style = "font-size: 18px; left: 24px; top: 24px; position: absolute" text = "Current time on the Web Server:"/> 27 28 <ui:staticText binding = "#{Time.clockText}" id = "clockText" style = "background-color: black; color: yellow; font-size: 18px; left: 24px; top: 29 30 31 32 33 34 35 34 Outline Set up a Static Text element Time.jsp (2 of 2 ) 48px; position: absolute"/> </ui:form> </ui:body> </ui:html> 36 </ui:page> 37 </f:view> 38 </jsp:root>  2007 Pearson Education, Inc. All rights reserved. 35 26.5.1 Examining a JSP File  Java Studio Creator 2 generates a JSP file in response to your interactions with the Visual Editor  All JSPs have a jsp:root element – version attribute indicates the version of JSP being used – One or more xmlns attributes. Each xmlns attribute specifies a prefix and a URL for a tag library, allowing the page to use tags specified in that library.  All JSPs generated by Java Studio Creator 2 include the tag libraries for – – – – JSF core components library JSF HTML components library JSP standard components library JSP user interface components library  1992-2007 Pearson Education, Inc. All rights reserved. 36 26.5.1 Examining a JSP File  The jsp:directive.page element – contentType attribute - specifies the MIME type and the character set the page uses – pageEncoding attribute - specifies the character encoding used by the page source – These attributes help the client determine how to render the content  All pages containing JSF components are represented in a component tree with the root JSF element f:view (of type UIViewRoot) – All JSF component elements are placed in this element  Many ui page elements have a binding attribute to bind their values to properties in the web application’s JavaBeans – JSF Expression Language is used to perform these bindings.  1992-2007 Pearson Education, Inc. All rights reserved. 37 26.5.1 Examining a JSP File  ui:head element – title attribute that specifies the page’s title  ui:link element – can be used to specify the CSS stylesheet used by a page  ui:body element – defines the body of the page  ui:form element – defines a form in a page.  ui:staticText component – displays text that does not change  1992-2007 Pearson Education, Inc. All rights reserved. 38 26.5.1 Examining a JSP File  JSP elements are mapped to XHTML elements for rendering in a browser – Can map to different XHTML elements, depending on the client browser and the component’s property settings  ui:staticText component – Typically maps to an XHTML span element – A span element contains text that is displayed on a web page and is used to control the formatting of the text – style attribute of ui:staticText represented as part of the corresponding span element’s style attribute  1992-2007 Pearson Education, Inc. All rights reserved. 39 Fig. 26.5 | Sample JSF component tree.  2007 Pearson Education, Inc. All rights reserved. 40 26.5.2 Examining a Page Bean File  Page bean classes – Inherit from class AbstractPageBean (package com.sun.rave.web.ui.appbase – Provides page life-cycle methods  Package com.sun.rave.web.ui.component includes classes for many basic JSF components  A ui:staticText component is a StaticText object (package com.sun.rave.web.ui.component).  1992-2007 Pearson Education, Inc. All rights reserved. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 // Fig. 26.6: Time.java // Page bean file that sets clockText to the time on the web server. package webtime; import import import import import import import import import import import com.sun.rave.web.ui.appbase.AbstractPageBean; com.sun.rave.web.ui.component.Body; com.sun.rave.web.ui.component.Form; com.sun.rave.web.ui.component.Head; com.sun.rave.web.ui.component.Html; com.sun.rave.web.ui.component.Link; com.sun.rave.web.ui.component.Page; javax.faces.FacesException; com.sun.rave.web.ui.component.StaticText; java.text.DateFormat; java.util.Date; 41 Outline Time.java (1 of 8 ) public class Time extends AbstractPageBean { private int __placeholder; // auto-generated component initialization method. private void _init() throws Exception { // empty body } // end method _init  2007 Pearson Education, Inc. All rights reserved. 27 28 private Page page = new Page(); 29 public Page getPage() 30 31 32 33 34 35 36 { 37 38 } // end method setPage 39 40 41 private Html html = new Html(); 42 43 44 { 45 46 47 48 49 return page; } // end method getPage public void setPage( Page page ) { this.page = page; 42 Outline Time.java (2 of 8 ) public Html getHtml ) return html; } // end method getHtml public void setHtml( Html html ) { this.html = html; } // end method setHtml 50 51 52 53 54 public Head getHead() { 55 56 return head; } // end method getHead private Head head = new Head();  2007 Pearson Education, Inc. All rights reserved. 57 58 public void setHead( Head head ) 59 { 60 61 62 this.head = head; } // end method setHead 63 64 65 private Link link = new Link(); 66 67 { 68 } // end method getLink 43 public Link getLink() Outline Time.java (3 of 8 ) return link; 69 70 71 72 public void setLink( Link link ) { this.link = link; 73 74 75 76 77 } // end method setLink 78 { 79 80 return body; } // end method getBody 81 82 public void setBody( Body body ) 83 { 84 85 this.body = body; } // end method setBody private Body body = new Body(); public Body getBody()  2007 Pearson Education, Inc. All rights reserved. 86 87 private Form form = new Form(); 88 89 public Form getForm() 44 90 91 { 92 93 } // end method getForm 94 95 96 public void setForm( Form form ) { this.form = form; 97 98 99 100 } // end method setForm 101 102 public StaticText getTimeHeader() { 103 104 105 return timeHeader; } // end method getStaticText1 106 public void setTimeHeader( StaticText st ) 107 108 109 { return form; Outline Time.java (4 of 8 ) private StaticText timeHeader = new StaticText(); this.timeHeader = st; } // end method setTimeHeader 110  2007 Pearson Education, Inc. All rights reserved. 111 112 private StaticText clockText = new StaticText(); 113 114 115 116 public StaticText getClockText() { return clockText; } // end method getClockText 117 118 119 120 121 122 123 124 125 126 127 128 Code that was Outline inserted by the designer to create a StaticText object 45 Time.java (5 of 8 ) public void setClockText( StaticText st ) { this.clockText = st; } // end method setClockText // Construct a new page bean instance. public Time() { // empty constructor } // end constructor  2007 Pearson Education, Inc. All rights reserved. 129 // Return a reference to the scoped data bean. 130 protected RequestBean getRequestBean() 131 { 132 133 Outline return (RequestBean) getBean( "RequestBean" ); } // end method getRequestBean 134 135 136 137 138 // Return a reference to the scoped data bean. protected ApplicationBean getApplicationBean() { return (ApplicationBean) getBean( "ApplicationBean" ); 139 140 } // end method getApplicationBean 141 142 143 144 // Return a reference to the scoped data bean. protected SessionBean getSessionBean() { return (SessionBean) getBean( "SessionBean" ); 145 146 147 148 149 } // end method getSessionBean 150 151 152 153 154 46 Time.java (6 of 8 ) // initializes page content public void init() { super.init(); try { _init(); } // end try  2007 Pearson Education, Inc. All rights reserved. 155 catch ( Exception e ) 156 157 158 { 159 160 new FacesException( e ); } // end catch log( "Time Initialization Failure", e ); throw e instanceof FacesException ? ( FacesException ) e: 161 162 } // end method init 163 164 // method called when a postback occurs. public void preprocess() 165 { 166 167 // empty body } // end method preprocess 47 Outline Time.java (7 of 8 )  2007 Pearson Education, Inc. All rights reserved. 168 48 169 // method called before the page is rendered. 170 171 172 173 public void prerender() { clockText.setValue( DateFormat.getTimeInstance( DateFormat.LONG ).format( new Date() ) ); 174 175 176 177 178 } // end method prerender // method called after rendering completes, if init was public void destroy() { Outline Programmatically change the text in Time.java the StaticText object (8 of 8 ) called. 179 // empty body 180 } // end method destroy 181 } // end class Time  2007 Pearson Education, Inc. All rights reserved. 49 26.5.3 Event-Processing Life Cycle  Java Studio Creator 2’s application model – Places methods init, preprocess, prerender and destroy in the page bean that tie into the JSF event-processing life cycle – These represent four major stages—initialization, preprocessing, prerendering and destruction  init method – Called by the JSP container the first time the page is requested and on postbacks – Postback occurs when form data is submitted, and the page and its contents are sent to the server to be processed – invokes its superclass version, then tries to call the method _init, which handles component initialization tasks  1992-2007 Pearson Education, Inc. All rights reserved. 50 26.5.3 Event-Processing Life Cycle  preprocess method – Called after init, but only if the page is processing a postback  prerender method – Called just before a page is rendered by the browser – Should be used to set component properties  destroy method – Called after the page has been rendered, but only if the init method was called – Handles tasks such as freeing resources used to render the page  1992-2007 Pearson Education, Inc. All rights reserved. 51 26.5.4 Relationship Between the JSP and Page Bean Files  Page bean – has a property for every element that appears in the JSP file  1992-2007 Pearson Education, Inc. All rights reserved. 52 26.5.5 Examining the XHTML Generated by a Java Web Application  To create a new web application – – – – – – File > New Project… Select Web in the Categories pane Select JSF Web Application in the Projects pane Click Next Specify the project name and location Click Finish to create the web application project  Single web page named Page1 created and opened by default in the Visual Editor in Design mode when the project first loads  Design mode shows how your page renders in abrowser  The JSP file for this page, named Page1.jsp, can be viewed by – clicking the JSP button at the top of the Visual Editor, or – right clicking anywhere in the Visual Editor and selecting Edit JSP Source.  1992-2007 Pearson Education, Inc. All rights reserved. 53 26.5.5 Examining the XHTML Generated by a Java Web Application  Preview in Browser button at the top of the Visual Editor window allows you to view your pages in a browser without having to build and run the application  The Refresh button redraws the page in the Visual Editor  The Target Browser Size drop-down list allows you to specify the optimal browser resolution for viewing the page and allows you to see what the page will look like in different screen resolutions  1992-2007 Pearson Education, Inc. All rights reserved. 54 26.5.5 Examining the XHTML Generated by a Java Web Application  Projects window displays the hierarchy of all the project’s files – Web Pages node contains the JSP files and includes the resources folder, which contains the project’s CSS stylesheet and any other files the pages may need to display properly (e.g., images) – The Java source code, including the page bean file for each web page and the application, session and request scope beans, can be found under the Source Packages node  Page Navigation file – Defines rules for navigating the project’s pages  1992-2007 Pearson Education, Inc. All rights reserved. 55 26.5.5 Examining the XHTML Generated by a Java Web Application  Methods init, preprocess, prerender and destroy are overridden in each page bean – Serve as placeholders for you to customize the behavior of your web application  Rename the JSP and Java files in your project, so that their names are relevant to your application – – – – Right click the JSP file in the Projects Window Select Rename to display the Rename dialog Enter the new file name If Preview All Changes is checked, the Refactoring Window will appear at the bottom of the IDE when you click Next > – No changes will be made until you click Do Refactoring in the Refactoring Window. – If you do not preview the changes, refactoring occurs when you click Next > in the Rename dialog.  1992-2007 Pearson Education, Inc. All rights reserved. 56 26.5.5 Examining the XHTML Generated by a Java Web Application  Refactoring – the process of modifying source code to improve its readability and reusability without changing its behavior – Examples: renaming methods or variables, breaking long methods into shorter ones – Java Studio Creator 2 has built-in refactoring tools that automate some refactoring tasks  Title property specifies JSPs title  Components are rendered using absolute positioning  Java Studio Creator 2 is a WYSIWYG (What You See Is What You Get) editor  Outline window displays the page bean and the request, session and application scope beans  Clicking an item in the page bean’s component tree selects the item in the Visual Editor  1992-2007 Pearson Education, Inc. All rights reserved. 57 26.5.5 Examining the XHTML Generated by a Java Web Application  To build and run application – Select Build > Build Main Project – Select Run > Run Main Project  If changes are made to a project, the project must be rebuilt before the changes will be reflected when the application is viewed in a browser  F5 – build an application, then run it in debug mode  <Ctrl> F5 – Program executes without debugging enabled.  1992-2007 Pearson Education, Inc. All rights reserved. 1 2 3 4 <?xml version = "1.0"?>   5 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 6 "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 7 <html xmlns = "http://www.w3.org/1999/xhtml"> 8 <head> 9 <meta content = "no-cache" http-equiv = "Pragma" /> 10 <meta content = "no-cache" http-equiv = "Cache-Control" /> 11 <meta content = "no-store" http-equiv = "Cache-Control" /> 12 <meta content = "max-age=0" http-equiv = "Cache-Control" /> 13 <meta content = "1" http-equiv = "Expires" /> 14 15 16 17 <title>Web Time: A Simple Example</title> <script type = "text/javascript" src = "/WebTime/theme/com/sun/rave/web/ui/defaulttheme/ javascript/formElements.js"></script> 18 19 20 21 22 <link rel = "stylesheet" type = "text/css" href = "/WebTime/theme/ com/sun/rave/web/ui/defaulttheme/css/css_master.css" /> <link rel = "stylesheet" type = "text/css" href = "/WebTime/theme/ com/sun/rave/web/ui/defaulttheme/css/css_ie55up.css" /> <script type = "text/javascript"> 23 24 25 var sjwuic_ScrollCookie = new sjwuic_ScrollCookie( '/Time.jsp', '/WebTime/faces/Time.jsp' ); </script> 58 Outline Time.html (1 of 2 )  2007 Pearson Education, Inc. All rights reserved. 26 <link id = "link" rel = "stylesheet" type = "text/css" 27 href = "/WebTime/resources/stylesheet.css" /> 28 29 </head> <meta id = "_id0" http-equiv = "refresh" content = "5" /> 30 31 32 33 34 35 <body id = "body" style = "-rave-layout: grid"> <form id = "form" class = "form" method = "post" action = "/WebTime/faces/Time.jsp" enctype = "application/x-www-form-urlencoded"> <span id = "form:timeHeader" style = "font-size: 18px; left: 24px; top: 24px; position: absolute">Current time on the Web Server: 36 37 38 39 40 41 </span> <span id = "form:clockText" style = "background-color: black; color: yellow; font-size: 18px; left: 24px; top: 48px; position: 59 Outline Time.html (2 of code 2 ) that HTML was generated for a StaticText object absolute">1:18:58 AM EDT</span> <input id = "form_hidden" name = "form_hidden" value = "form_hidden" type = "hidden" /> 42 </form> 43 </body> 44 </html>  2007 Pearson Education, Inc. All rights reserved. 60 Fig. 26.8 | Visual Editor window in Design mode.  2007 Pearson Education, Inc. All rights reserved. 61 Fig. 26.9 | Palette in Java Studio Creator 2.  2007 Pearson Education, Inc. All rights reserved. 62 Fig. 26.10 | Projects window for the WebTime project.  2007 Pearson Education, Inc. All rights reserved. 63 Fig. 26.11 | JSP file generated for Page1 by Java Studio Creator 2.  2007 Pearson Education, Inc. All rights reserved. 64 Fig. 26.12 | Page bean file for Page1.jsp generated by Java Studio Creator 2.  2007 Pearson Education, Inc. All rights reserved. 65 Fig. 26.13 | Time.jsp after inserting the first Static Text component.  2007 Pearson Education, Inc. All rights reserved. 66 Fig. 26.14 | Time.jsp after adding the second Static Text component.  2007 Pearson Education, Inc. All rights reserved. 67 Fig. 26.15 | Outline window in Java Studio Creator 2.  2007 Pearson Education, Inc. All rights reserved. 68 Error-Prevention Tip 26.1 If you have trouble building your project due to errors in the Java Studio Creatorgenerated XML files used for building, try cleaning the project and building again. You can do this by selecting Build > Clean and Build Main Project or by pressing <Alt> B.  2007 Pearson Education, Inc. All rights reserved. 69 26.6 JSF Components  1992-2007 Pearson Education, Inc. All rights reserved. 70 JSF Components Description Label Displays text that can be associated with an input element. Static Text Displays text that the user cannot edit. Text Field Gathers user input and displays text. Button Triggers an event when clicked. Hyperlink Displays a hyperlink. Drop Down List Displays a drop-down list of choices. Radio Button Group Groups radio buttons. Image Displays images (e.g., GIF and JPG). Fig. 26.16 | Commonly used JSF components.  2007 Pearson Education, Inc. All rights reserved. 71 26.6.1 Text and Graphics Components  Grid Panel component – Designer can specify number of columns the grid should contain – Drop components anywhere inside the panel – They’ll automatically be repositioned into evenly spaced columns in the order in which they are dropped – When the number of components exceeds the number of columns, the panel moves the additional components to a new row  Image component – Inserts an image into a web page – Images must be placed in the project’s resources folder – Use url property to specify the image to display  1992-2007 Pearson Education, Inc. All rights reserved. 72 26.6.1 Text and Graphics Components  Text Field – Used to obtain text input from the user  Component’s JSP tags are added to the JSP file in the order they are added to the page.  Tabbing between components navigates the components in the order in which the JSP tags occur in the JSP file  To specify navigation order – Drag components onto the page in appropriate order, or – Set each input field’s Tab Index property; tab index 1 is the first in the tab sequence  1992-2007 Pearson Education, Inc. All rights reserved. 73 26.6.1 Text and Graphics Components  Drop Down List – displays a list from which the user can make a selection – To configure, right click the drop-down list in Design mode and select Configure Default Options  Hyperlink – Adds a link to a web page – url property specifies the linked resource  Radio Button Group – Provides a series of radio buttons – Edit options by right clicking the component and selecting Configure Default Options  Button – Triggers an action when clicked – Typically maps to an input XHTML element with attribute type set to submit.  1992-2007 Pearson Education, Inc. All rights reserved. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 <?xml version = "1.0" encoding = "UTF-8"?>   <jsp:root version = "1.2" xmlns:f = "http://java.sun.com/jsf/core" xmlns:h = "http://java.sun.com/jsf/html" xmlns:jsp = "http://java.sun.com/JSP/Page" xmlns:ui = "http://www.sun.com/web/ui"> <jsp:directive.page contentType = "text/html; charset = UTF-8" pageEncoding = "UTF-8"/> <f:view> <ui:page binding = "#{WebComponents.page}" id = "page"> <ui:html binding = "#{WebComponents.html}" id = "html"> <ui:head binding = "#{WebComponents.head}" id = "head"> <ui:link binding = "#{WebComponents.link}" id = "link" url = "/resources/stylesheet.css"/> </ui:head> <ui:body binding = "#{WebComponents.body}" id = "body" style = "-rave-layout: grid"> <ui:form binding = "#{WebComponents.form}" id = "form"> <ui:staticText binding = "#{WebComponents.header}" id = "header" style = "font-size: 18px; left: 24px; top: 24px; position: absolute" text = "This is a sample registration form."/> <ui:staticText binding = "#{WebComponents.instructions}" id = "instructions" style = "font-style: italic; left: 24px; top: 72px; position: absolute" text = "Please fill in all fields and click Register."/> 74 Outline WebComponents .jsp (1 of 5 )  2007 Pearson Education, Inc. All rights reserved. 28 29 30 31 <ui:image binding = "#{WebComponents.userImage}" id = "userImage" style = "left: 24px; top: 120px; position: absolute" url = "/resources/user.JPG"/> <h:panelGrid binding = "#{WebComponents.gridPanel}" 32 33 columns = "4" id = "gridPanel" style = "height: 96px; left: 24px; top: 168px; position: absolute" 34 35 width = "576"> <ui:image binding = "#{WebComponents.fnameImage}" 36 37 38 id = "fnameImage" url = "/resources/fname.png"/> <ui:textField binding = "#{WebComponents.fnameTf}" id = "fnameTf"/> 39 40 41 <ui:image binding = "#{WebComponents.lnameImage}" id = "lnameImage" url = "/resources/lname.JPG"/> <ui:textField binding = "#{WebComponents.lnameTF}" 42 <ui:image binding = "#{WebComponents.emailImage}" id = "emailImage" url = "/resources/email.JPG"/> <ui:textField binding = "#{WebComponents.emailTF}" 46 47 id = "emailTF"/> <ui:image binding = "#{WebComponents.phoneImage}" 49 50 51 75 Designer generated code for Grid WebComponents Panel .jsp Designer (2 of 5 )generated code for Text Field id = "lnameTF"/> 43 44 45 48 Designer generated Outline code for Image id = "phoneImage" url = "/resources/phone.JPG"/> <ui:textField binding = "#{WebComponents.phoneTF}" id = "phoneTF" label = "Must be in the form (555) 555-5555"/> 52 </h:panelGrid> 53 54 <ui:image binding = "#{WebComponents.publicationsImage}" id = "publicationsImage" style = "position: absolute; 55 left: 24px; top: 288px" url = 56 "/resources/publications.JPG"/>  2007 Pearson Education, Inc. All rights reserved. 57 58 59 60 61 <ui:staticText binding = "#{WebComponents.publicationLabel}" id = "publicationLabel" style = "left: 240px; top: 288px; position: absolute" text = "Which book would you like information about?"/> 62 63 64 <ui:dropDown binding = "#{WebComponents.booksDropDown}" id = "bookcDropDown" items = "#{WebComponents. booksDropDownDefaultOptions.options}" style = "left: 65 66 67 24px; top: 336px; position: absolute; width: 240px"/> <ui:hyperlink binding = "#{WebComponents.deitelLink}" id = "deitelLink" style = "left: 24px; top: 384px; 68 position: absolute" target = "_blank" text = "Click 69 70 71 "osImage" style = "position: absolute; left: 24px; 73 top: 432px" url = "/resources/os.JPG"/> 77 Outline Designer generated WebComponents code for Drop .jsp Down List (3 of 5 ) Designer generated code for Hyperlink here for more information about our books." url = "http://www.deitel.com"/> <ui:image binding = "#{WebComponents.osImage}" id = 72 74 75 76 76 <ui:staticText binding = "#{WebComponents.osLabel}" id = "osLabel" style = "left: 240px; top: 432px; position: absolute" text = "Which operating system are you using?"/>  2007 Pearson Education, Inc. All rights reserved. 78 79 <ui:radioButtonGroup binding = "#{WebComponents.osRadioButtonGroup}" id = "osRadioButtonGroup" items = "#{WebComponents. 80 81 82 83 84 85 86 87 osRadioButtonGroupDefaultOptions.options}" style = "left: 24px; top: 504px; position: absolute"/> <ui:button binding = "#{WebComponents.registerButton}" id = "registerButton" style = "left: 23px; top: 648px; position: absolute" text = "Register"/> </ui:form> </ui:body> Designer generated Outline code for Radio Button Group 77 Designer generated WebComponents code for Button .jsp (4 of 5 ) 88 </ui:html> 89 </ui:page> 90 </f:view> 91 </jsp:root>  2007 Pearson Education, Inc. All rights reserved. 78 Outline WebComponents .jsp (5 of 5 )  2007 Pearson Education, Inc. All rights reserved. 79 26.6.2 Validation Using Validator Components and Custom Validators  Validation – Helps prevent processing errors due to incomplete or improperly formatted user input.  Length Validator – Determines whether a field contains an acceptable number of characters  Double Range Validators and Long Range Validators – Determine whether numeric input falls within acceptable ranges  Package javax.faces.validators contains the validator classes  1992-2007 Pearson Education, Inc. All rights reserved. 80 26.6.2 Validation Using Validator Components and Custom Validators  Label component – Describes another component – Can be associated with a user input field by setting its for property  Message component – Displays an error message when validation fails  To associate a Label or Message component with another component, hold the Ctrl and Shift keys, then drag the Label or Message to the appropriate component  1992-2007 Pearson Education, Inc. All rights reserved. 81 26.6.2 Validation Using Validator Components and Custom Validators  Set the required property of a component to ensure that the user enters data for it.  An input field’s required property must be set to true for validation to occur  In the Visual Editor the label for a required field is automatically marked by a red asterisk.  If a user submits a form with a missing required field, the default error message for that field will be displayed in its associated ui:message component  1992-2007 Pearson Education, Inc. All rights reserved. 82 26.6.2 Validation Using Validator Components and Custom Validators  To edit a Double Range Validator’s or a Long Range Validator’s properties – Click its node in the Outline window in Design mode – Set the maximum and minimum properties in the Properties window  Can limit user input length using validation – Set a Text Field’s maxLength property  1992-2007 Pearson Education, Inc. All rights reserved. 83 26.6.2 Validation Using Validator Components and Custom Validators  To ensure properly formatted input – Can match input against a regular expression  No built in regular expression, but you can add your own custom validator methods to the page bean file  Add a custom validator method – Right click the appropriate input component – Select Edit Event Handler > validate to create a validation method in the page bean file  1992-2007 Pearson Education, Inc. All rights reserved. 1 <?xml version = "1.0" encoding = "UTF-8"?> 2 3  4 5  <jsp:root version = "1.2" xmlns:f = "http://java.sun.com/jsf/core" 6 7 8 9 xmlns:h = "http://java.sun.com/jsf/html" xmlns:jsp = "http://java.sun.com/JSP/Page" xmlns:ui = "http://www.sun.com/web/ui"> <jsp:directive.page contentType = "text/html; charset = UTF-8" pageEncoding = "UTF-8"/> 10 11 <f:view> <ui:page binding = "#{Validation.page}" id = "page"> 12 13 14 15 18 <ui:body binding = "#{Validation.body}" focus = "form1:nameTF" 23 24 25 26 Validation.jsp (1 of 6 ) title = "Validation"> <ui:link binding = "#{Validation.link}" id = "link" url = "/resources/stylesheet.css"/> </ui:head> 21 22 Outline <ui:html binding = "#{Validation.html}" id = "html"> <ui:head binding = "#{Validation.head}" id = "head" 16 17 19 20 84 id = "body" style = "-rave-layout: grid"> <ui:form binding = "#{Validation.form}" id = "form"> <ui:staticText binding = "#{Validation.header}" id = "header" style = "font-size: 16px; height: 22px; left: 24px; top: 24px; position: absolute; width: 456px" text = "Please fill out the following form."/> <ui:staticText binding = "#{Validation.instructions}" id = "instructions" style = "font-size: 14px; 27 28 font-style: italic; left: 24px; top: 48px; position: absolute; width: 406px" text = "All fields are 29 required and must contain valid information."/>  2007 Pearson Education, Inc. All rights reserved. 30 <ui:textField binding = "#{Validation.nameTF}" columns = 31 "30" id = "nameTF" required = "true" style = "left: 32 33 168px; top: 96px; position: absolute; width: 216px" validator = 34 35 36 37 38 39 40 "#{Validation.nameLengthValidator.validate}"/> <ui:textField binding = "#{Validation.emailTF}" columns = "28" id = "emailTF" required = "true" style = "left: 168px; top: 144px; position: absolute; width: 216px" validator = "#{Validation.emailTF_validate}"/> <ui:textField binding = "#{Validation.phoneTF}" 41 42 43 columns = "30" id = "phoneTF" required = "true" style = "left: 168px; top: 192px; position: absolute; width: 216px" validator = 44 "#{Validation.phoneTF_validate}"/> 45 46 47 <ui:label binding = "#{Validation.nameLabel}" for = "nameTF" id = "nameLabel" style = "font-weight: normal; height: 24px; left: 24px; top: 96px; 48 49 position: absolute; width: 94px" text = "Name:"/> <ui:label binding = "#{Validation.emailLabel}" for = 50 "emailTF" id = "emailLabel" style = "font-weight: 51 52 53 normal; height: 24px; left: 24px; top: 144px; position: absolute; width: 142px" text = "Email Address:"/> 54 <ui:label binding = "#{Validation.phoneLabel}" for = 55 56 "phoneTF" id = "phoneLabel" style = "font-weight: normal; height: 24px; left: 24px; top: 192px; 57 position: absolute; width: 142px" text = 58 "Phone number:"/> 85 Outline Specifies the validator for the Validation.jsp name Text Field (2 of Specifies the6 ) validator for the email Text Field Specifies the validator for the phone number Text Field  2007 Pearson Education, Inc. All rights reserved. 59 60 61 62 63 64 65 66 67 68 69 70 <ui:button action = "#{Validation.submitButton_action}" binding = "#{Validation.submitButton}" id = "submitButton" style = "left: 23px; top: 240px; position: absolute; width: 72px" text = "Submit"/> <ui:message binding = "#{Validation.emailMessage}" for = "emailTF" id = "emailMessage" showDetail = "false" showSummary = "true" style = "left: 408px; top: 144px; position: absolute"/> <ui:message binding = "#{Validation.phoneMessage}" for = "phoneTF" id = "phoneMessage" showDetail = "false" <ui:message binding = "#{Validation.nameMessage}" for = "nameTF" id = "nameMessage" showDetail = "false" showSummary = "true" style = "left: 408px; top: 96px; 74 75 76 position: absolute"/> <ui:staticText binding = "#{Validation.resultText}" escape = "false" id = "resultText" rendered = "false" 77 78 79 80 81 style = "height: 46px; left: 24px; top: 288px; position: absolute; width: 312px" text = "Thank you for your submission.
<br/>We received the following information:"/> <h:panelGrid bgcolor = "seashell" binding = 87 88 Outline Validation.jsp (3 of 6 ) showSummary = "true" style = "left: 408px; top: 192px; position: absolute"/> 71 72 73 82 83 84 85 86 86 "#{Validation.gridPanel}" columns = "2" id = "gridPanel" rendered = "false" style = "height: 96px; left: 24px; top: 336px; position: absolute" width = "312"> <ui:staticText binding = "#{Validation.nameResultLabel}" id = "nameResultLabel" text = "Name:"/>  2007 Pearson Education, Inc. All rights reserved. 89 90 <ui:staticText binding = "#{Validation.nameResult}" id = "nameResult"/> 91 <ui:staticText binding = "emailResultLabel" text = "E-mail address:"/> <ui:staticText binding = "#{Validation.emailResult}" id = "emailResult"/> <ui:staticText binding = "#{Validation.phoneResultLabel}" id = 93 94 95 96 97 Validation.jsp (4 of 6 ) "phoneResultLabel" text ="Phone number:"/> 98 <ui:staticText binding = "#{Validation.phoneResult}" id = "phoneResult"/> 99 100 </h:panelGrid> </ui:form> 101 102 106 Outline "#{Validation.emailResultLabel}" id = 92 103 104 105 87 </ui:body> </ui:html> </ui:page> </f:view> 107 </jsp:root>  2007 Pearson Education, Inc. All rights reserved. 88 Outline Validation.jsp (5 of 6 )  2007 Pearson Education, Inc. All rights reserved. 89 Outline Validation.jsp (6 of 6 )  2007 Pearson Education, Inc. All rights reserved. 90 26.7 Session Tracking  Personalization – Makes it possible for e-businesses to communicate effectively with their customers – Improves the user’s ability to locate desired products and services  Privacy – Some consumers embrace the idea of tailored content – Others fear the possible adverse consequences if the information they provide to e-businesses is released or collected by tracking technologies  1992-2007 Pearson Education, Inc. All rights reserved. 91 26.7 Session Tracking  To provide personalized services, must be able to recognize clients  HTTP is a stateless protocol – It does not support persistent connections that would enable web servers to maintain state information regarding particular clients  To help the server distinguish among clients, each client must identify itself to the server  Tracking individual clients – Cookies – SessionBean object  1992-2007 Pearson Education, Inc. All rights reserved. 92 26.7 Session Tracking  Other tracking methods – "hidden" form elements - A web form can write session-tracking data into a form - When the user submits the form, all the form data, including the "hidden" fields, is sent to the form handler on the web server – URL rewriting - Web server embeds session-tracking information directly in the URLs of hyperlinks that the user clicks to send subsequent requests  1992-2007 Pearson Education, Inc. All rights reserved. 93 26.7.1 Cookies  Cookie – A piece of data typically stored in a text file on the user’s computer – Maintains information about the client during and between browser sessions  When a user visits the website, the user’s computer might receive a cookie – This cookie is then reactivated each time the user revisits that site  HTTP-based interactions between a client and a server – Includes a header containing information either about the request (when the communication is from the client to the server) or about the response (when the communication is from the server to the client)  1992-2007 Pearson Education, Inc. All rights reserved. 94 26.7.1 Cookies  In a request, the header includes – Request type – Any cookies that have been sent previously from the server to be stored on the client machine  In a response, the header includes – Any cookies the server wants to store on the client computer – Other information, such as the MIME type of the response  Expiration date determines how long the cookie remains on the client’s computer – If not set, the web browser maintains the cookie for the browsing session’s duration  1992-2007 Pearson Education, Inc. All rights reserved. 95 26.7.1 Cookies  Setting the action handler for a Hyperlink enables you to respond to a click without redirecting the user to another page  To add an action handler to a Hyperlink that should also direct the user to another page – Add a rule to the Page Navigation file – Right click in the Visual Designer and select Page Navigation…, then drag the appropriate Hyperlink to the destination page  1992-2007 Pearson Education, Inc. All rights reserved. 96 26.7.1 Cookies  A cookie object is an instance of class Cookie in package javax.servlet.http  An HttpServletResponse (from package javax.servlet.http) represents the response – This object can be accessed by invoking the method getExternalContext on the page bean, then invoking getResponse on the resulting object  An HttpServletRequest (from package javax.servlet.http) represents the request – This object can be obtained by invoking method getExternalContext on the page bean, then invoking getRequest on the resulting object.  HttpServletRequest method getCookies returns an array of the cookies previously written to the client.  Web server cannot access cookies created by servers in other domains  1992-2007 Pearson Education, Inc. All rights reserved. 1 // Fig. 26.19: Validation.java 2 // Page bean for validating user input and redisplaying that input if 3 // valid. 4 5 package validation; 6 import com.sun.rave.web.ui.appbase.AbstractPageBean; 7 8 9 10 import import import import com.sun.rave.web.ui.component.Body; com.sun.rave.web.ui.component.Form; com.sun.rave.web.ui.component.Head; com.sun.rave.web.ui.component.Html; 11 12 13 14 import import import import com.sun.rave.web.ui.component.Link; com.sun.rave.web.ui.component.Page; javax.faces.FacesException; com.sun.rave.web.ui.component.StaticText; 97 Outline Validation.java (1 of 5 ) 15 import com.sun.rave.web.ui.component.TextField; 16 import com.sun.rave.web.ui.component.TextArea; 17 import com.sun.rave.web.ui.component.Label; 18 import com.sun.rave.web.ui.component.Button; 19 import com.sun.rave.web.ui.component.Message; 20 import javax.faces.component.UIComponent; 21 import javax.faces.context.FacesContext; 22 23 24 25 import import import import javax.faces.validator.ValidatorException; javax.faces.application.FacesMessage; javax.faces.component.html.HtmlPanelGrid; javax.faces.validator.LengthValidator;  2007 Pearson Education, Inc. All rights reserved. 26 98 27 public class Validation extends AbstractPageBean 28 { 29 Outline private int __placeholder; 30 31 32 33 34 private void _init() throws Exception { nameLengthValidator.setMaximum( 30 ); } // end method _init Validation.java (2 of 5 ) 35 36 // To save space, we omitted the code in lines 36-345. The complete 37 38 // source code is provided with this chapter's examples. 346 347 348 349 public Validation() { // empty constructor } // end constructor 350 351 352 353 354 355 356 357 358 359 protected RequestBean getRequestBean() { return (RequestBean) getBean( "RequestBean" ); } // end method getRequestBean protected ApplicationBean getApplicationBean() { return (ApplicationBean) getBean( "ApplicationBean" ); } // end method getApplicationBean 360  2007 Pearson Education, Inc. All rights reserved. 361 362 363 364 365 366 367 368 369 370 protected SessionBean getSessionBean() { return (SessionBean) getBean( "SessionBean" ); 99 Outline } // end method getSessionBean public void init() { super.init(); try { 371 372 _init(); } // end try 373 374 375 catch ( Exception e ) { log( "Validation Initialization Failure", e ); 376 377 378 throw e instanceof FacesException ? (FacesException) e: new FacesException( e ); } // end catch 379 380 381 382 383 } // end method init 384 385 386 387 388 } // end method preprocess 389 390 } // end method prerender Validation.java (3 of 5 ) public void preprocess() { // empty body public void prerender() { // empty body  2007 Pearson Education, Inc. All rights reserved. 391 392 public void destroy() { 393 394 // empty body } // end method destroy 100 Outline 395 396 397 398 399 400 401 // validates entered email address against the regular expression // that represents the form of a valid email address. public void emailTF_validate( FacesContext context, UIComponent component, Object value ) { String email = String.valueOf( value ); 402 403 404 // if entered email address is not in a valid format if ( !email.matches( "\\w+([-+.']\\w+)*@\\w+([-.]\\w+)*\\.\\w+([-.]\\w+)*" ) ) 405 406 { throw new ValidatorException( new FacesMessage( 407 408 409 410 411 "Enter a valid email address, e.g. [email protected]" ) ); } // end if } // end method emailTF_validate 412 413 414 // validates entered email address against the regular expression // that represents the form of a valid email address. public void phoneTF_validate( FacesContext context, 415 416 Validation.java (4 of 5 ) Custom email validation via regular expression UIComponent component, Object value ) { 417 String phone = String.valueOf( value ); 418 419 // if entered phone number is not in a valid format  2007 Pearson Education, Inc. All rights reserved. 420 421 if ( !phone.matches( "((\\(\\d{3}\\) ?)|(\\d{3}-))?\\d{3}-\\d{4}" ) ) 422 { 423 424 425 426 427 428 throw new ValidatorException( new FacesMessage( "Enter a valid phone number, e.g. (555) 555-1234" ) ); } // end if } // end method phoneTF_validate 429 430 431 432 433 434 public String submitButton_action() { String name = String.valueOf( nameTF.getValue() ); String email = String.valueOf( emailTF.getValue() ); String phone = String.valueOf( phoneTF.getValue() ); nameResult.setValue( name ); // displays validated form entries in a Grid Panel. 435 436 emailResult.setValue( email ); phoneResult.setValue( phone ); 437 438 439 440 gridPanel.setRendered( true ); resultText.setRendered( true ); return null; } // end method submitButton_action 101 Custom phone Outline number validation via regular expression Validation.java (5 of 5 ) 441 } // end class Validation  2007 Pearson Education, Inc. All rights reserved. 102 Portability Tip 26.1 Clients may disable cookies in their web browsers for more privacy. When such clients use web applications that depend on cookies to maintain state information, the applications will not execute correctly.  2007 Pearson Education, Inc. All rights reserved. 1 <?xml version = "1.0" encoding = "UTF-8"?> 2 3  4 5  <jsp:root version = "1.2" xmlns:f = "http://java.sun.com/jsf/core" 6 7 8 9 xmlns:h = "http://java.sun.com/jsf/html" xmlns:jsp = "http://java.sun.com/JSP/Page" xmlns:ui = "http://www.sun.com/web/ui"> <jsp:directive.page contentType = "text/html; charset = UTF-8" pageEncoding = "UTF-8"/> 10 11 <f:view> <ui:page binding = "#{Options.page}" id = "page"> 12 13 14 15 Options.jsp (1 of 4 ) "Options"> <ui:link binding = "#{Options.link}" id = "link" url = "/resources/stylesheet.css"/> </ui:head> 18 <ui:body binding = "#{Options.body}" id = "body" 21 22 Outline <ui:html binding = "#{Options.html}" id = "html"> <ui:head binding = "#{Options.head}" id = "head" title = 16 17 19 20 103 style = "-rave-layout: grid"> <ui:form binding = "#{Options.form}" id = "form"> <ui:label binding = "#{Options.languageLabel}" for = "languageList" id = "languageLabel" style = 23 24 "font-size: 16px; font-weight: bold; left: 24px; top: 24px; position: absolute" text = "Select a 25 26 programming language:"/> <ui:radioButtonGroup binding = "#{Options.languageList}" 27 28 id = "languageList" items = "#{Options.languageListOptions.options}" style = 29 "left: 24px; top: 48px; position: absolute"/>  2007 Pearson Education, Inc. All rights reserved. 30 31 <ui:staticText binding = "#{Options.responseLabel}" id = "responseLabel" rendered = "false" style = 32 33 "font-size: 16px; font-weight: bold; height: 24px; left: 24px; top: 24px; position: absolute; 34 35 width: 216px"/> <ui:hyperlink action = "#{Options.languagesLink_action}" 36 37 binding = "#{Options.languagesLink}" id = "languagesLink" rendered = "false" style = "left: 24px; top: 96px; position: absolute" text = "Click here to choose another language."/> <ui:hyperlink action = 38 39 40 41 42 "#{Options.recommendationsLink_action}" binding = "#{Options.recommendationsLink}" id = 43 44 45 46 "recommendationsLink" rendered = "false" style = "left: 24px; top: 120px; position: absolute" text = "Click here to get book recommendations." url = "/faces/Recommendations.jsp"/> 47 <ui:button action = "#{Options.submit_action}" binding = Outline Options.jsp (2 of 4 ) "#{Options.submit}" id = "submit" style = "left: 23px; top: 192px; position: absolute" text = 48 49 "Submit"/> </ui:form> </ui:body> 50 51 52 53 54 55 104 </ui:html> </ui:page> </f:view> 56 </jsp:root>  2007 Pearson Education, Inc. All rights reserved. 105 Outline Options.jsp (3 of 4 )  2007 Pearson Education, Inc. All rights reserved. 106 Outline Options.jsp (4 of 4 )  2007 Pearson Education, Inc. All rights reserved. 107 Fig. 26.21 | Editing the Page Navigation file.  2007 Pearson Education, Inc. All rights reserved. 1 2 // Fig. 26.22: Options.java // Page bean that stores the user’s language selection as a cookie on the 3 4 // client. package cookies; 108 Outline 5 6 7 8 9 10 11 import import import import import import com.sun.rave.web.ui.appbase.AbstractPageBean; com.sun.rave.web.ui.component.Body; com.sun.rave.web.ui.component.Form; com.sun.rave.web.ui.component.Head; com.sun.rave.web.ui.component.Html; com.sun.rave.web.ui.component.Link; Options.java (1 of 6 ) 12 import com.sun.rave.web.ui.component.Page; 13 import javax.faces.FacesException; 14 import com.sun.rave.web.ui.component.StaticText; 15 import com.sun.rave.web.ui.component.Label; 16 import com.sun.rave.web.ui.component.RadioButtonGroup; 17 18 19 20 import import import import com.sun.rave.web.ui.model.SingleSelectOptionsList; com.sun.rave.web.ui.component.Hyperlink; com.sun.rave.web.ui.component.Button; javax.servlet.http.HttpServletResponse; 21 22 23 24 25 import javax.servlet.http.Cookie; import java.util.Properties; 26 27 private int __placeholder; public class Options extends AbstractPageBean {  2007 Pearson Education, Inc. All rights reserved. 28 29 // method _init initializes components and sets the // options for the radio button group. 30 31 32 private void _init() throws Exception { languageListOptions.setOptions( new com.sun.rave.web.ui.model.Option[] { new com.sun.rave.web.ui.model.Option( "Java", "Java" ), 33 34 35 new com.sun.rave.web.ui.model.Option( "C", "C" ), new com.sun.rave.web.ui.model.Option( "C++", "C++" ), new com.sun.rave.web.ui.model.Option( "Visual/Basic/2005", 36 37 38 Outline Options.java (2 of 6 ) "Visual Basic 2005" ), 39 new com.sun.rave.web.ui.model.Option( "Visual/C#/2005", "Visual C# 2005" ) 40 41 42 43 109 } ); 44 } // end method _init 45 46 47 // To save space, we omitted the code in lines 46-203. The complete // source code is provided with this chapter's examples. 48  2007 Pearson Education, Inc. All rights reserved. 204 private Properties books = new Properties(); 205 206 // Construct a new page bean instance and initialize the properties 207 208 // that map languages to ISBN numbers of recommended books. public Options() 209 { 210 211 212 // initialze the Properties object of values to be stored as // cookies. books.setProperty( "Java", "0-13-222220-5" ); 213 books.setProperty( "C", "0-13-142644-3" ); 214 215 books.setProperty( "C++", "0-13-185757-6" ); books.setProperty( "Visual/Basic/2005", "0-13-186900-0" ); 216 books.setProperty( "Visual/C#/2005", "0-13-152523-9" ); 217 } // end Options constructor 218 219 protected ApplicationBean getApplicationBean() 220 221 222 223 224 225 226 227 228 229 230 { 231 232 233 return (SessionBean) getBean( "SessionBean" ); } // end method getSessionBean 110 Outline Options.java (3 of 6 ) return (ApplicationBean) getBean( "ApplicationBean" ); } // end method getApplicationBean protected RequestBean getRequestBean() { return (RequestBean) getBean( "RequestBean" ); } // end method getRequestBean protected SessionBean getSessionBean() {  2007 Pearson Education, Inc. All rights reserved. 234 public void init() 235 { 236 super.init(); 237 238 try { _init(); 239 } // end try catch ( Exception e ) { 240 241 242 243 log( "Options Initialization Failure", e ); 244 245 throw e instanceof FacesException ? ( FacesException ) e: new FacesException( e ); 246 } // end catch 247 } // end method init 248 249 public void preprocess() 250 251 252 253 254 255 256 257 258 259 260 { 261 262 263 // empty body } // end method destroy 111 Outline Options.java (4 of 6 ) // empty body } // end method preprocess public void prerender() { // empty body } // end method prerender public void destroy() {  2007 Pearson Education, Inc. All rights reserved. 264 265 // Action handler for the Submit button. Checks to see if a language // was selected and if so, registers a cookie for that language and 266 267 // sets the responseLabel to indicate the chosen language. public String submit_action() 268 269 270 271 { String msg = "Welcome to Cookies! You "; if ( languageList.getSelected() != null ) 273 274 275 276 { Outline Options.java // if the user made a selection 272 112 (5 of 6 ) String language = languageList.getSelected().toString(); String displayLanguage = language.replace( '/', ' ' ); msg += "selected " + displayLanguage + "."; 277 278 279 280 281 // get ISBN number of book for the given language. String ISBN = books.getProperty( language ); 282 283 284 Cookie cookie = new Cookie( language, ISBN ); // add cookie to the response header to place it on the user's 285 286 // machine HttpServletResponse response = 287 288 (HttpServletResponse) getExternalContext().getResponse(); response.addCookie( cookie ); 289 // create cookie using language-ISBN name-value pair } // end if Creates the Cookie object Gets the response object and adds the Cookie to the response  2007 Pearson Education, Inc. All rights reserved. else 290 msg += "did not select a language."; 291 292 293 responseLabel.setValue( msg ); 294 languageList.setRendered( false ); 295 languageLabel.setRendered( false ); 296 297 298 299 submit.setRendered( false ); responseLabel.setRendered( true ); languagesLink.setRendered( true ); recommendationsLink.setRendered( true ); 300 301 return null; // reloads the page } // end method submit_action 302 303 304 305 // redisplay the components used to allow the user to select a // language. public String languagesLink_action() 306 307 308 309 310 113 Outline Options.java (6 of 6 ) { responseLabel.setRendered( false ); languagesLink.setRendered( false ); recommendationsLink.setRendered( false ); languageList.setRendered( true ); 311 languageLabel.setRendered( true ); 312 submit.setRendered( true ); 313 return null; 314 } // end method languagesLink_action 315 } // end class Options  2007 Pearson Education, Inc. All rights reserved. 114 Software Engineering Observation 26.1 Java Studio Creator 2 can automatically import any missing packages your Java file needs. For example, after adding the Properties object to Options.java, you can right click in the Java editor window and select Fix Imports to automatically import java.util.Properties.  2007 Pearson Education, Inc. All rights reserved. 1 2 <?xml version = "1.0" encoding = "UTF-8"?> 3  4 5 6  <jsp:root version = "1.2" xmlns:f = "http://java.sun.com/jsf/core" xmlns:h = "http://java.sun.com/jsf/html" xmlns:jsp = 7 8 9 "http://java.sun.com/JSP/Page" xmlns:ui = "http://www.sun.com/web/ui"> <jsp:directive.page contentType = "text/html; charset = UTF-8" pageEncoding = "UTF-8"/> 10 11 <f:view> <ui:page binding = "#{Recommendations.page}" id = "page"> 12 13 14 15 16 17 18 19 20 21 115 Outline Recommendations .jsp (1 of 2 ) <ui:html binding = "#{Recommendations.html}" id = "html"> <ui:head binding = "#{Recommendations.head}" id = "head" title = "Recommendations"> <ui:link binding = "#{Recommendations.link}" id = "link" url = "/resources/stylesheet.css"/> </ui:head> <ui:body binding = "#{Recommendations.body}" id = "body" style = "-rave-layout: grid"> <ui:form binding = "#{Recommendations.form}" id = "form"> <ui:label binding = "#{Recommendations.languageLabel}" 22 for = "booksListBox" id = "languageLabel" style = 23 24 "font-size: 20px; font-weight: bold; left: 24px; top: 24px; position: absolute" text = "Recommendations"/> 25 26 <ui:listbox binding = "#{Recommendations.booksListBox}" id = "booksListBox" items = "#{Recommendations. 27 booksListBoxOptions.options}" rows = "6" style = 28 29 "left: 24px; top: 72px; position: absolute; width: 360px"/>  2007 Pearson Education, Inc. All rights reserved. <ui:hyperlink action = "case1" binding = "#{Recommendations.optionsLink}" id = "optionsLink" 30 31 style = "left: 24px; top: 192px; position: absolute" text = "Click here to choose another language."/> 32 33 </ui:form> </ui:body> 34 35 36 37 </ui:html> </ui:page> 38 </f:view> 39 </jsp:root> 116 Outline Recommendations .jsp (2 of 2 )  2007 Pearson Education, Inc. All rights reserved. 1 // Fig. 26.24: Recommendations.java 2 3 // Page bean that displays book recommendations based on cookies storing // user’s selected programming languages. 4 package cookies; 5 6 import com.sun.rave.web.ui.appbase.AbstractPageBean; 7 8 import com.sun.rave.web.ui.component.Body; import com.sun.rave.web.ui.component.Form; 9 import com.sun.rave.web.ui.component.Head; 10 import com.sun.rave.web.ui.component.Html; 117 Outline Recommendations .java (1 of 4 ) 11 import com.sun.rave.web.ui.component.Link; 12 import com.sun.rave.web.ui.component.Page; 13 import javax.faces.FacesException; 14 import com.sun.rave.web.ui.component.Listbox; 15 16 17 18 import import import import com.sun.rave.web.ui.model.DefaultOptionsList; com.sun.rave.web.ui.component.Label; com.sun.rave.web.ui.component.Hyperlink; com.sun.rave.web.ui.model.Option; 19 import javax.servlet.http.HttpServletRequest; 20 import javax.servlet.http.Cookie; 21 import com.sun.rave.web.ui.component.HiddenField; 22 23 public class Recommendations extends AbstractPageBean 24 { 25 private int __placeholder; 26 27 private void _init() throws Exception 28 { 29 // empty body 30 } // end method _init()  2007 Pearson Education, Inc. All rights reserved. 31 32 33 118 // To save space, we omitted the code in lines 32-151. The complete // source code is provided with this chapter's examples. Outline 34 152 153 public Recommendations() { 154 155 // empty body } // end constructor 156 157 158 159 160 161 protected RequestBean getRequestBean() { return (RequestBean) getBean( "RequestBean" ); } // end method getRequestBean 162 163 protected ApplicationBean getApplicationBean() { 164 165 166 167 168 return (ApplicationBean) getBean( "ApplicationBean" ); } // end method getApplicationBean 169 170 171 Recommendations .java (2 of 4 ) protected SessionBean getSessionBean() { return (SessionBean) getBean( "SessionBean" ); } // end method getSessionBean  2007 Pearson Education, Inc. All rights reserved. 172 173 174 public void init() { super.init(); 175 176 try { 177 178 179 _init(); } // end try catch ( Exception e ) 180 181 { log( "Recommendations Initialization Failure", e ); 119 Outline Recommendations .java (3 of 4 ) throw e instanceof FacesException ? (FacesException) e: new FacesException( e ); 182 183 184 185 } // end catch } // end method init 186 187 188 public void preprocess() { 189 190 191 192 // empty body } // end method preprocess 193 { public void prerender() 194 195 //retrieve client's cookies HttpServletRequest request = 196 197 198 (HttpServletRequest)getExternalContext().getRequest(); Cookie [] cookies = request.getCookies(); 199 200 201 // if there are cookies, store the corresponding books and ISBN // numbers in an array of Options Option [] recommendations; Obtains the Cookie object(s) from the request  2007 Pearson Education, Inc. All rights reserved. 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 120 if ( cookies.length > 1 ) { recommendations = new Option[ cookies.length - 1 ]; for ( int i = 0; i < cookies.length - 1; i++ ) { String language = cookies[ i ].getName().replace( ’/’, ’ ’ ); recommendations[ i ] = new Option( language + " How to " "Program. ISBN#: " + cookies[ i ].getValue() ); } // end for } // end if Outline Recommendations .java (4 of 4 ) // otherwise store a message indicating no language was selected else { recommendations = new Option[ 1 ]; recommendations[ 0 ] = new Option( "No recommendations. " + "Please select a language." ) ; } // end else booksListBox.setItems( recommendations ); } // end method prerender public void destroy() { // empty body } // end method destroy 230 } // end class Recommendations  2007 Pearson Education, Inc. All rights reserved. 121 Methods Description getDomain Returns a String containing the cookie’s domain (i.e., the domain from which the cookie was written). This determines which web servers can receive the cookie. By default, cookies are sent to the web server that originally sent the cookie to the client. Changing the Domain property causes the cookie to be returned to a web server other than the one that originally wrote it. getMaxAge Returns an int indicating how many seconds the cookie will persist on the browser. This is –1 by default, meaning the cookie will persist until the browser is shut down. getName Returns a String containing the cookie’s name. getPath Returns a String containing the path to a directory on the server to which the cookie applies. Cookies can be “targeted” to specific directories on the web server. By default, a cookie is returned only to applications operating in the same directory as the application that sent the cookie or a subdirectory of that directory. Changing the Path property causes the cookie to be returned to a directory other than the one from which it was originally written. getSecure Returns a bool value indicating whether the cookie should be transmitted through a secure protocol. The value true causes a secure protocol to be used. getValue Returns a String containing the cookie’s value. Fig. 26.25 | javax.servlet.http.Cookie methods.  2007 Pearson Education, Inc. All rights reserved. 122 26.7.2 Session Tracking with the SessionBean Object  Can perform session tracking with class SessionBean that is provided in each web application created with Java Studio Creator 2 – When a new client requests a web page in the project, a SessionBean object is created.  The SessionBean can be accessed throughout a session by invoking the method getSessionBean on the page bean – Can then use the SessionBean object to access stored session properties  To store information in the SessionBean – Add properties to the SessionBean class – To add a property - Right click the SessionBean node in the Outline window - Select Add > Property to display the New Property Pattern dialog - Configure the property and click OK to create it  1992-2007 Pearson Education, Inc. All rights reserved. 1 <?xml version = "1.0" encoding = "UTF-8"?> 2 3  4  5 <jsp:root version = "1.2" xmlns:f = "http://java.sun.com/jsf/core" 6 7 8 9 xmlns:h = "http://java.sun.com/jsf/html" xmlns:jsp = "http://java.sun.com/JSP/Page" xmlns:ui = "http://www.sun.com/web/ui"> <jsp:directive.page contentType = "text/html; charset = UTF-8" pageEncoding = "UTF-8"/> 10 <f:view> 11 12 13 14 15 16 17 Outline Options.jsp (1 of 5 ) <ui:page binding = "#{Options.page}" id = "page"> <ui:html binding = "#{Options.html}" id = "html"> <ui:head binding = "#{Options.head}" id = "head"> <ui:link binding = "#{Options.link}" id = "link" url = "/resources/stylesheet.css"/> </ui:head> <ui:body binding = "#{Options.body}" id = "body" 18 19 20 21 22 23 24 style = "-rave-layout: grid"> <ui:form binding = "#{Options.form}" id = "form"> <ui:label binding = "#{Options.languageLabel}" for = "languageList" id = "languageLabel" style = "font-size: 16px; font-weight: bold; left: 24px; top: 24px; position: absolute" text = "Select a programming language:"/> 25 26 27 <ui:radioButtonGroup binding = "#{Options.languageList}" id = "languageList" items = "#{Options.languageListOptions.options}" style = 28 123 "left: 24px; top: 48px; position: absolute"/>  2007 Pearson Education, Inc. All rights reserved. 29 <ui:button action = "#{Options.submit_action}" binding = 30 "#{Options.submit}" id = "submit" style = "left: 31 32 23px; top: 192px; position: absolute" text = "Submit"/> 33 <ui:staticText binding = "#{Options.responseLabel}" id = 34 35 36 "responseLabel" rendered = "false" style = "font-size: 16px; font-weight: bold; height: 24px; left: 24px; top: 24px; position: absolute; 37 width: 216px"/> 38 id = "numSelectedLabel" rendered = "false" style = "left: 24px; top: 96px; position: absolute" text = 41 "Number of selections so far:"/> 42 <ui:staticText binding = "#{Options.numSelected}" id = 43 44 "numSelected" rendered = "false" style = "left: 192px; top: 96px; position: absolute" text = 45 "#{SessionBean.numSelections}"/> 49 50 Outline Options.jsp (2 of 5 ) <ui:staticText binding = "#{Options.numSelectedLabel}" 39 40 46 47 48 124 <ui:hyperlink action = "#{Options.languagesLink_action}" binding = "#{Options.languagesLink}" id = "languagesLink" rendered = "false" style = "left: 24px; top: 144px; position: absolute" text = "Click here to choose another language."/>  2007 Pearson Education, Inc. All rights reserved. 51 52 <ui:hyperlink binding = "#{Options.recommendationsLink}" id = "recommendationsLink" rendered = "false" style = 53 54 55 "left: 24px; top: 168px; position: absolute" text = "Click here to get book recommendations." url = "/faces/Recommendations.jsp"/> 56 57 58 </ui:form> </ui:body> </ui:html> 59 </ui:page> 60 </f:view> 61 </jsp:root> 125 Outline Options.jsp (3 of 5 )  2007 Pearson Education, Inc. All rights reserved. 126 Outline Options.jsp (4 of 5 )  2007 Pearson Education, Inc. All rights reserved. 127 Outline Options.jsp (5 of 5 )  2007 Pearson Education, Inc. All rights reserved. 128 Fig. 26.27 | New Property dialog for adding a property to the SessionBean.  2007 Pearson Education, Inc. All rights reserved. 129 Fig. 26.28 | Bind to Data dialog.  2007 Pearson Education, Inc. All rights reserved. 1 2 // Fig. 26.29: SessionBean.java // SessionBean file for storing language selections. 3 4 package session; 5 import com.sun.rave.web.ui.appbase.AbstractSessionBean; 6 7 8 9 10 11 import java.util.Properties; import javax.faces.FacesException; public class SessionBean extends AbstractSessionBean { private int __placeholder; 12 13 14 private void _init() throws Exception { 15 16 // empty body } // end method _init 17 18 19 20 public SessionBean() { // empty constructor 21 22 23 24 25 } // end constructor 26 27 } // end method getApplicationBean 130 Outline SessionBean.java (1 of 3 ) protected ApplicationBean getApplicationBean() { return (ApplicationBean1) getBean( "ApplicationBean" );  2007 Pearson Education, Inc. All rights reserved. 28 29 public void init() { 30 super.init(); 31 32 33 try { _init(); 34 35 36 } // end try catch ( Exception e ) { 131 Outline SessionBean.java (2 of 3 ) log( "SessionBean Initialization Failure", e); throw e instanceof FacesException ? (FacesException) e: 37 38 new FacesException( e) ; 39 40 } // end catch 41 42 43 } // end method init 44 45 46 47 48 { 49 { 50 51 // empty body } // end method activate 52 53 public void destroy() 54 { 55 56 // empty body } // end method destroy public void passivate() // empty body } // end method passivate public void activate()  2007 Pearson Education, Inc. All rights reserved. 57 132 58 59 private int numSelections = 0; // stores number of unique selections 60 public int getNumSelections() 61 62 63 64 65 { 66 { 67 68 this.numSelections = numSelections; } // end method setNumSelections 69 70 71 72 73 74 75 76 return this.numSelections; } // end method getNumSelections SessionBean.java (3 of 3 ) public void setNumSelections( int numSelections ) // Stores key-value pairs of selected languages private Properties selectedLanguages = new Properties(); public Properties getSelectedLanguages() { return this.selectedLanguages; } // end method getSelectedLanguages Outline Manually coded Properties object 77 78 79 80 81 public void setSelectedLanguages( Properties selectedLanguages ) { this.selectedLanguages = selectedLanguages; } // end method setSelectedLanguages 82 } // end class SessionBean  2007 Pearson Education, Inc. All rights reserved. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 // Fig. 26.30: Options.java // Page bean that stores language selections in a SessionBean property. package session; import import import import import import import import import import import import import import import import import import com.sun.rave.web.ui.appbase.AbstractPageBean; com.sun.rave.web.ui.component.Body; com.sun.rave.web.ui.component.Form; com.sun.rave.web.ui.component.Head; com.sun.rave.web.ui.component.Html; com.sun.rave.web.ui.component.Link; com.sun.rave.web.ui.component.Page; javax.faces.FacesException; com.sun.rave.web.ui.component.RadioButtonGroup; com.sun.rave.web.ui.component.Hyperlink; com.sun.rave.web.ui.component.Button; com.sun.rave.web.ui.component.Label; com.sun.rave.web.ui.component.StaticText; com.sun.rave.web.ui.model.SingleSelectOptionsList; java.util.Properties; javax.servlet.http.Cookie; javax.servlet.http.HttpServletRequest; javax.servlet.http.HttpSession; 133 Outline Options.java (1 of 6 )  2007 Pearson Education, Inc. All rights reserved. 24 public class Options extends AbstractPageBean 25 { 26 private int __placeholder; 27 28 private void _init() throws Exception 29 30 31 32 33 34 35 { languageListOptions.setOptions( new com.sun.rave.web.ui.model.Option[] { Outline Options.java (2 of 6 ) new com.sun.rave.web.ui.model.Option( "Java", "Java" ), new com.sun.rave.web.ui.model.Option( "C", "C" ), new com.sun.rave.web.ui.model.Option( "C++", "C++" ), new com.sun.rave.web.ui.model.Option( "Visual Basic 2005", "Visual Basic 2005" ), new com.sun.rave.web.ui.model.Option( "Visual C# 2005", 36 37 38 "Visual C# 2005" ) 39 40 41 42 43 44 45 134 } ); } // end method init // To save space, we omitted the code in lines 44-219. The complete // source code is provided with this chapter's examples. 46  2007 Pearson Education, Inc. All rights reserved. 220 private Properties books = new Properties(); 221 222 223 public Options() { 224 // initialze the Properties object of values to be stored in 225 226 227 228 // the session bean. books.setProperty( "Java", "0-13-148398-6" ); books.setProperty( "C", "0-13-142644-3" ); books.setProperty( "C++", "0-13-185757-6" ); 229 books.setProperty( "Visual Basic 2005", "0-13-186900-0" ); 230 231 books.setProperty( "Visual C# 2005", "0-13-152523-9" ); } // end constructor 232 233 protected ApplicationBean getApplicationBean() 234 235 236 135 Outline Options.java (3 of 6 ) { return (ApplicationBean) getBean( "ApplicationBean" ); } // end method getApplicationBean 237 238 239 protected RequestBean getRequestBean() { 240 241 return (RequestBean) getBean( "RequestBean" ); } // end method getRequestBean 242 243 244 protected SessionBean getSessionBean() { 245 246 return (SessionBean) getBean( "SessionBean" ); } // end method getSessionBean 247  2007 Pearson Education, Inc. All rights reserved. 248 public void init() 249 { 250 super.init(); 251 252 try { _init(); 253 } // end try catch ( Exception e ) { 254 255 256 257 log( "Options Initialization Failure", e ); 258 259 throw e instanceof FacesException ? (FacesException) e: new FacesException( e ); 260 } // end catch 261 } // end method init 262 263 public void preprocess() 264 265 266 267 268 269 270 271 272 273 274 { 275 276 277 // empty body } // end method destroy 136 Outline Options.java (4 of 6 ) // empty body } // end method preprocess public void prerender() { // empty body } // end method prerender public void destroy() {  2007 Pearson Education, Inc. All rights reserved. 278 // action handler for the submit button, stores selected languages 279 // in session scope for retrieval when making book recommendations. 280 public String submit_action() 281 { 282 String msg = "Welcome to sessions! 137 Outline You "; Options.java 283 284 // if the user made a selection 285 if ( getLanguageList().getSelected() != null ) 286 { 287 String language = languageList.getSelected().toString(); 288 msg += "selected " + language + "."; (5 of 6 ) 289 290 // get ISBN number of book for the given language. 291 String ISBN = books.getProperty( language ); 292 293 // add the selection to the SessionBean's Properties object 294 Properties selections = getSessionBean().getSelectedLanguages(); 295 Object result = selections.setProperty( language, ISBN ); Add a recommendation 296 297 // increment numSelections in the SessionBean and update 298 // selectedLanguages if the user has not made this selection 299 // before 300 if ( result == null ) 301 { 302 int numSelected = getSessionBean().getNumSelections(); 303 getSessionBean().setNumSelections( ++numSelected ); 304 305 } // end if } // end if  2007 Pearson Education, Inc. All rights reserved. 306 307 else msg += "did not select a language."; 308 309 310 responseLabel.setValue( msg ); languageList.setRendered( false ); 311 languageLabel.setRendered( false ); 312 313 314 submit.setRendered( false ); responseLabel.setRendered( true ); numSelectedLabel.setRendered( true ); 315 numSelected.setRendered( true ); 316 languagesLink.setRendered( true ); 317 318 319 recommendationsLink.setRendered( true ); return null; } // end method submit_action 320 321 322 // redisplay the components used to allow the user to select a // language. 323 public String languagesLink_action() { 324 325 326 327 responseLabel.setRendered( false ); numSelectedLabel.setRendered( false ); numSelected.setRendered( false ); languagesLink.setRendered( false ); 328 329 recommendationsLink.setRendered( false ); languageList.setRendered( true ); 330 languageLabel.setRendered( true ); 331 submit.setRendered( true ); 138 Outline Options.java (6 of 6 ) 332 return null; 333 } // end method languagesLink_action 334 } // end class Options  2007 Pearson Education, Inc. All rights reserved. 139 Software Engineering Observation 26.2 A benefit of using SessionBean properties (rather than cookies) is that they can store any type of object (not just Strings) as attribute values. This provides you with increased flexibility in maintaining client state information.  2007 Pearson Education, Inc. All rights reserved. 1 <?xml version = "1.0" encoding = "UTF-8"?> 2 3 4   <jsp:root version = "1.2" xmlns:f = "http://java.sun.com/jsf/core" 7 8 xmlns:h = "http://java.sun.com/jsf/html" xmlns:jsp = "http://java.sun.com/JSP/Page" xmlns:ui = "http://www.sun.com/web/ui"> 9 10 11 <jsp:directive.page contentType = "text/html; charset = UTF-8" pageEncoding = "UTF-8"/> <f:view> 12 13 14 15 16 17 18 Recommendations .jsp (1 of 2 ) <ui:link binding = "#{Recommendations.link}" id = "link" url = "/resources/stylesheet.css"/> </ui:head> <ui:body binding = "#{Recommendations.body}" id = "body" style = "-rave-layout: grid"> <ui:form binding = "#{Recommendations.form}" id = "form"> 21 <ui:label binding = "#{Recommendations.languageLabel}" 25 Outline <ui:page binding = "#{Recommendations.page}" id = "page"> <ui:html binding = "#{Recommendations.html}" id = "html"> <ui:head binding = "#{Recommendations.head}" id = "head"> 19 20 22 23 24 140 for = "booksListBox" id = "languageLabel" style = "font-size: 20px; font-weight: bold; left: 24px; top: 24px; position: absolute" text = "Recommendations"/> <ui:listbox binding = "#{Recommendations.booksListBox}" 26 27 id = "booksListBox" items = "#{Recommendations. booksListBoxDefaultOptions.options}" rows = "6" 28 style = "left: 24px; top: 72px; position: absolute; 29 width: 360px"/>  2007 Pearson Education, Inc. All rights reserved. 30 <ui:hyperlink action = "case1" binding = 31 "#{Recommendations.optionsLink}" id = "optionsLink" 32 style = "left: 24px; top: 192px; position: absolute" 33 text = "Click here to choose another language."/> 34 </ui:form> 35 </ui:body> 36 </ui:html> 37 </ui:page> 38 </f:view> 39 </jsp:root> 141 Outline Recommendations .jsp (2 of 2 )  2007 Pearson Education, Inc. All rights reserved. 1 // Fig. 26.32: Recommendations.java 2 3 // Page bean that displays book recommendations based on a SessionBean // property. 4 package session; 5 6 import com.sun.rave.web.ui.appbase.AbstractPageBean; 7 8 import com.sun.rave.web.ui.component.Body; import com.sun.rave.web.ui.component.Form; 9 import com.sun.rave.web.ui.component.Head; 10 import com.sun.rave.web.ui.component.Html; 142 Outline Recommendations .java (1 of 4 ) 11 import com.sun.rave.web.ui.component.Link; 12 import com.sun.rave.web.ui.component.Page; 13 import javax.faces.FacesException; 14 import com.sun.rave.web.ui.component.Listbox; 15 16 17 18 import import import import com.sun.rave.web.ui.component.Label; com.sun.rave.web.ui.component.Hyperlink; com.sun.rave.web.ui.model.DefaultOptionsList; java.util.Enumeration; 19 import com.sun.rave.web.ui.model.Option; 20 import java.util.Properties; 21 22 public class Recommendations extends AbstractPageBean 23 { 24 private int __placeholder; 25 26 private void _init() throws Exception 27 { 28 // empty body 29 } // end method _init 30  2007 Pearson Education, Inc. All rights reserved. 31 // To save space, we omitted the code in lines 31-150. The complete 32 33 // source code is provided with this chapter's examples. 151 public Recommendations() 152 153 { 154 155 } // end constructor 156 protected RequestBean getRequestBean() 157 { // empty constructor Outline Recommendations .java (2 of 4 ) return (RequestBean) getBean( "RequestBean" ); 158 159 160 } // end method getRequestBean 161 protected ApplicationBean getApplicationBean() 162 163 164 165 { 166 167 168 protected SessionBean getSessionBean() { return (SessionBean) getBean( "SessionBean" ); 169 170 171 172 173 174 175 176 } // end method getSessionBean 177 143 return (ApplicationBean) getBean( "ApplicationBean" ); } // end method getApplicationBean public void init() { super.init(); try { _init(); } // end try  2007 Pearson Education, Inc. All rights reserved. catch ( Exception e ) { 178 179 log( "Recommendations Initialization Failure", e ); throw e instanceof FacesException ? (FacesException) e: 180 181 144 Outline new FacesException( e ); 182 183 184 185 186 } // end catch } // end method init 187 188 189 { public void preprocess() Recommendations .java (3 of 4 ) // empty body } // end method preprocess 190 191 192 193 public void prerender() { //retrieve user's selections and number of selections made 194 Properties languages = getSessionBean().getSelectedLanguages(); 195 196 197 198 Enumeration selectionsEnum = languages.propertyNames(); int numSelected = getSessionBean().getNumSelections(); Option [] recommendations; 199 200 // if at least one selection was made 201 202 if ( numSelected > 0 ) { 203 Obtains the objects needed to retrieve the users selections recommendations = new Option[ numSelected ]; 204  2007 Pearson Education, Inc. All rights reserved. 205 for ( int i = 0; i < numSelected; i++ ) 206 { 145 207 String language = (String) selectionsEnum.nextElement() ; 208 209 recommendations[ i ] = new Option( language + "How to Program. ISBN#:" + 210 211 212 languages.getProperty( language ) ); } // end for } // end if 213 214 215 216 else { recommendations = new Option[ 1 ]; recommendations[ 0 ] = new Option( "No recommendations. 217 218 219 "Please select a language." ); } // end else 220 booksListBox.setItems( recommendations ); 221 222 223 224 225 226 Outline Creates recommendations for the Recommendations user .java (4 of 4 ) " + } // end method prerender public void destroy() { // empty body } // end method destroy 227 } // end class Recommendations  2007 Pearson Education, Inc. All rights reserved.

Top subcategories

Top subcategories

Top subcategories

Top subcategories

Top subcategories

Top subcategories

Top subcategories

Top subcategories

Download ppt