JSP: The Complete Reference - Yola

1 JSP: The Complete ReferenceAbout the Hanna has more than 20 years experienceas a programmer, systems architect, analyst, andproject manager. He has developed network-basedsoftware at IBM, and served as a consultant toChase Manhattan Bank. He is the author ofInstant Java Servlets,and works as a softwaredeveloper for SAS 2001 The McGraw-Hill Companies, Inc. Click Here for Terms of : The CompleteReferencePhil HannaOsborne/McGraw-HillNew York Chicago San FranciscoLisbon London Madrid Mexico CityMilan New Delhi San JuanSeoul Singapore Sydney TorontoCopyright 2001 by The McGraw-Hill Companies. All rights reserved. Manufactured in the United States of America. Except as per-mitted under the United States Copyright Act of 1976, no part of this publication may be reproduced or distributed in any form or byany means, or stored in a database or retrieval system, without the prior written permission of the publisher.

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5 32 Evolution of the Web Application ..53 Overview of the Hypertext Transfer Protocol (HTTP) ..114 Introduction to Servlets ..235 JSP Overview ..53 Part IIElements of JSP6 JSP Syntax and Semantics ..637 Expressions and Scriptlets ..898 Declarations ..1119 Request Dispatching ..13310 The Page Directive ..16111 JSP Tag Extensions ..183viiCopyright 2001 The McGraw-Hill Companies, Inc. Click Here for Terms of IIIJSP in Action12 HTML Forms ..26113 Database Access ..29114 Session and Thread Management ..35315 JSP and JavaBeans ..41516 JSP and XML ..45117 JSP Testing and Debugging ..49318 Deploying Web Applications ..52919 Case Study: A Product Support Center ..551 Part IVJSP and Other Web Components20 Communicating with Other Clients ..67921 Communicating with Other Servers ..703 Part VAppendixesAServlet API Version.

6 723 BJSP API Version ..793 CHTTP Reference ..833 Index ..845viiiJSP: The Complete ReferenceContentsPreface..xixAcknowledgm ents..xxvPart IThe Web Programming Environment1 The Web Marketplace ..32 Evolution of the Web Application ..5 Birth of the Web ..6 Growth of the Web Programming Model ..6 The Shift from Client-Side to Server-Side Solutions ..93 Overview of the Hypertext Transfer Protocol (HTTP) ..11 What Is HTTP? ..12A Language for Requesting Documents overthe Internet ..12 The HTTP Specification ..12ixCopyright 2001 The McGraw-Hill Companies, Inc. Click Here for Terms of : The Complete ReferenceHTTP Request Model ..13 Connecting to the Web Server ..14 Sending the HTTP Request ..15 Server Acceptance of the Request ..16 The HTTP Response from the Server ..16 Examples ..17 Summary ..214 Introduction to Servlets.

7 23 Servlet Lifecycle ..24init ..25service ..26destroy ..27 Example: Kilometers per Liter to Miles per Gallon Servlet ..27 Servlet Classes ..31 Servlet ..32 Servlet Request ..36 Servlet Response ..41 Servlet Context ..44 Threading Models ..47 SingleThreadModel ..49 HTTP Sessions ..49 The HttpSession Interface ..50 Summary ..525 JSP Overview ..53 How JSP Works ..54A Basic Example ..56 Part IIElements of JSP6 JSP Syntax and Semantics ..63 The JSP Development Model ..64 Components of a JSP Page ..65 Directives ..65 Comments ..68 Expressions ..69 Scriptlets ..70 Declarations ..71 ContentsxiImplicit Objects ..74 Standard Actions ..75 Tag Extensions ..78A Complete Example ..78A Page Directive ..83A <jsp:include> Action ..83 Scriptlet ..84 JSP Expressions ..85A Declaration..86 Summary.

8 877 Expressions and Scriptlets ..89 Expressions ..90 Scriptlets ..91 Expression and Scriptlet Handling by the JSP Container ..93 HTML Template Data and Expressions ..94 Scriptlet Contents ..94 Container-Generated Initialization and Exit Code ..96 Implicit Objects and the JSP Environment ..97 Request ..98 Response ..99 PageContext ..100 Session ..102 Application ..103 Out ..104 Config ..106 Page ..106 Exception ..106 Initialization Parameters ..107 Summary ..1098 Declarations ..111 What Is a Declaration? ..112 Where Declaration Code Is Generated ..112 Primary Uses for Declarations ..117 Variable Declarations ..117 Thread Safety and Instance Variables ..118 Method Definitions ..122 Overriding jspInit and jspDestroy ..126 Access to Implicit Objects ..128 Inner Classes ..1289 Request Dispatching.

9 133 Anatomy of Request Processing ..134 Including Other Resources ..136 The include Directive ..136 How It Works ..137 Effect of Changes in an Included File ..138 Using the include Directive to Copy Source Code ..139 The <jsp:include> Action ..140 How It Works ..141 Which Method to Use ..153 Forwarding Requests ..154 The RequestDispatcher Object ..158 Request Dispatching vs. Redirection ..159 Model 1 vs. Model 2 ..159 Summary ..16010 The Page Directive ..161language ..162extends ..164 Required Interfaces for a JSP Superclass ..164A JSP Superclass Example ..166import ..170session ..172buffer and autoFlush ..172isThreadSafe ..173info ..174contentType ..174errorPage and isErrorPage ..176 Summary ..18111 JSP Tag Extensions ..183 Why Custom Tags? ..184 Developing Your First Custom Tag.

10 186 Step 1 Define the Tag ..186 Step 2 Create the TLD Entry ..187 Step 3 Write the Tag Handler ..188 Step 4 Incorporate the Tag into a JSP Page ..192 How Tag Handlers Work ..194 What the JSP Container Does ..194 What a Tag Handler Does ..196 Tag Libraries ..197 The Tag Library Descriptor (TLD) ..197 The taglib Directive ..199xiiJSP: The Complete ReferenceThe Tag Handler API ..200 The Tag Interface ..200 The TagSupport Class ..202 The Tag Handler Life Cycle ..202 The Flowchart ..204An Example of Generated Code ..206 Defining Tag Attributes ..212 The Body Tag Handler API ..219 BodyContent ..219 The BodyTag Interface ..221 The BodyTagSupport Class ..222 The Body Tag Handler Life Cycle ..223 The Flowchart ..223 Defining Scripting Variables ..226 The TagExtraInfo Class ..227 Validating Tag Attributes.