Java Thin-Client Programming for a Network Computing Environment

Transcription

1 Java Thin-Client Programming for a Network Computing Environment JÜRGEN FRIEDRICHS HENRI J I B I N AND THE JALAPENO TEAM / - : / :.. : :. ISBN PRENTICE HALL PTR, UPPER SADDLE RIVER, NEW JERSEY

2 <Son+enfs List of Figures, xiii List of Tables, xix Preface, xxi The Team That Wrote This Book, xxiv The Jalapeno Team, xxv Comments Welcome, xxvii Chapter I Introduction, 1 A Thin Client Application The Lunar Medical Center Story, 3 About the Book, 4 Who Should Read This Book, 7 Assumptions, 7 How to Use This Book, 7

3 Java Thin-Client Programming for a Network Computing Environment Chapter 2 Network Computing and Network Computers, 9 Network Computing Ideals, 11 Network Computing Reality, 12 Problems with Network Computing, 13 The Network Computer (NC), 14 NC Objectives, 15 NC Capabilities and Architecture, 16 NC Product Example: The IBM Network Station 1000,18 A Network Computing Strategy, 21 Chapter 3 Distributed Applications, 23 The Monolithic, Nondistributed Alternative, 24 A Look at Some Issues, 25 Considering Distributed Systems Design & Development Strategies, 29 In Summary, 34 Chapter 4 HTML-Based Clients, 35 Browsers and Web Servers, 37 HTML Overview, 39 HTML Conformance, 39 Developing in HTML, 40 Simple Example, 41 Forms and Tables, 42 To Validate or Not to Validate..., 44 Client Intelligence JavaScript, 45 Simple JavaScript Examples, 47 Using JavaScript, 50

4 Contents Chapter 5 Java-Based Clients, 55 A Brief Overview of Java, 56 Client-Server Computing with Java, 61 Applets, 61 Sockets in Java, 63 Accessing an HTTP Server with Java, 66 Object-Object Communication: Remote Method Invocation (RMI), 66 Connecting to the Database: JDBC, 67 The Lunar Medical Center's Java Application, 69 The Lunar Medical Center's Java Applet, 73 Some Java Facilities Supporting Enterprise-Wide Network Computing, 76 In Summary, 79 Chapter 6 Design Decisions, 81 Designing the Object Model for the Lunar Medical Center's Systems, 82 Designing the Applications: Considering Alternatives, 85 Profiles Describing the Check-In Applet, 85 Profiles Describing the Main Patient View/Edit Application, 86 Profiles Considered but Not Implemented, 87 Additional Factors to be Considered, 87 The Lunar Medical Center Implementations, 88 Nondistributed Full Application Based on Files, 90 HTML Only at the Browser with a Servlet at the Server, 91 HTML and JavaScript with HTTP to a Servlet, 92 Applet at the Browser with HTTP Connection to Java Servlet, 93 Applet with Direct JDBC Connection, 94 Java Application Using JDBC Directly, 95 Full Application Using Sockets, 95 Full Java Application Using Java RMI, 96 In Summary, 97

5 Java Thin-Client Programming for a Network Computing Environment Chapter 7 Java Servlets and HTTP Communication, 99 Overview of the Hypertext Transfer Protocol and Request Methods, 100 Protocol Steps, 101 HTTP Headers and Server Status Codes, 103 Client Request Methods 106 Common Gateway Interface, 108 Using CGI, 109 Problems with CGI, 111 Java Servlets, 111 Servlet Requirements and Usage, 112 The LMC's HTTP/Servlet Implementation, 117 In Summary, 120 Chapter 8 Java Servers Using JDBC, 123 Overview of JDBC, 124 JDBC API, 125 JDBC/SQL Data Type Mapping, 126 JDBC Database Drivers, 128 Using JDBC, 130 The LMC's JDBC Implementation, 133 Chapter 9 Java Servers and Socket Communication, 141 Introduction to TCP/IP sockets, 142 Sockets with Java, 144 Compatibility of Different Socket Implementations, 144 The LMC's Socket Implementation, 145 Implementing the Socket Client, 146 Implementing the Socket Server, 147 In Summary, 150

6 Chapter 10 Java Servers and RMI Communication, 151 RMI: An Easy Way to Implement Java Client/Server Applications, 151 The RMI Architecture, 152 Stub and Skeleton Layer, 153 Remote Reference Layer, 154 Transport Layer, 154 RMI Method Invocation Mechanism, 154 RMI from a Programmer's Perspective, 155 Server Side, 155 Client Side, 155 RMI Security Manager, 158 RMI Registry, 158 Major RMI Classes, 158 Developing with RMI, 159 The LMC's RMI Implementation, 161 The RMI Server Interface, 161 The RMI Server Class, 162 The RMI Client Class, 164 In Summary, 165 Chapter II Client Diets, 167 Looking at the Options, 168 The Compiler and Tools, 169 Packaging, Class Loading and Pre-Initialization, 170 Object Recycling, 172 Garbage Collection, 173 Optimizing Memory Accesses, 175 Synchronization Overheads, 176 Error Handling, 178 Other Issues and Optimizations, 178 In Summary, 179

7 Java Thin-Client Programming for a Network Computing Environment Chapter 12 Tasty Additions, 181 Introduction to SmartCards, 181 The SmartCard File System, 185 The OpenCard Framework, 186 Sample SmartCard Application, 189 Accessing a Serial Port, 192 X-10 Architecture and Protocols, 193 Programming the X-10 CP290 Home Control Interface, 193 The Java Espresso Machine Example, 194 Chapter 13 NC Deployment: Using IBM Network Stations, 197 Introduction, 198 Software Requirements, 198 The Initialization Process, 199 The Power-On Self-Test, 200 Locating the Boot Server, 201 Loading the Kernel, 202 Initiate the Environment, 203 IBM Network Station Set Up, 204 The NVRAM Setup Utility Panel, 204 Set Network Parameters Panel, 205 Set the Boot Parameters Panel 208 The IBM NetworkStation Manager, 210 The Configuration Files, 212 The Configuration File Syntax, 212 System-Level Configuration Files, 213 Workstation-Level Configuration Files, 214 User-Level Configuration Files, 215 The Startup Files, 215 The IBM Network Station User Services, 216 The IBM Network Station Message Log, 218

8 Local Session, 218 Allowing Remote Telnet Session, 219 Remote Telnet Session, 220 Accessing the Serial Port, 221 Allowing Access to the Serial Port, 222 Initializing the Serial Port, 222 Coming Soon: IBM Software Release 3, 224 The Setup Utility Panel, 224 IBM Network Station Manager, 224 Java Support, 224 Chapter 14 Java in the IBM Network Station, 227 Introduction, 227 Java Virtual Machine, 228 Memory Requirements, 228 Java Settings, 229 Running Java Programs in the IBM Network Station, 229 Adding a Java Applet Item to the Taskbar, 230 Adding a Java Application Item to the Taskbar, 231 Autostarting Java Programs and Applets, 233 Troubleshooting Java Execution Problems, 234 The esuite, 236 The Workplace, 236 The Administrator, 238 Adding a Java Applet, 239 Appendix A Brief HTML Reference, 247 Top Level Tags, 247 Character Formatting Tags, 248 Block Formatting Tags, 248 Table Tags, 249 List Tags, 250

9 Jovo Thin-Client Programming for a Network Computing Environment Forms Tags, 251 Miscellaneous Tags, 252 Appendix B Java Development: Using VisualAge for Java, 255 The VisualAge Family, 256 VisualAge for Java Overview, 257 Integrated Development Environment (IDE), 260 Java Support, 260 Navigating within VisualAge for Java, 263 Starting VisualAge for Java, 264 How It Fits Together, 271 Extending the Application, 287 Team Development, 294 Applet Viewer, 297 Editor /Debugger/SmartGuides, 299 Other VisualAge for Java Windows, 305 SmartGuides/Wizards, 306 Proxy Builder, 307 Enterprise Access Builders (EAB), 308 Data Access Builder (DAX), 308 System Requirements, 309 Summary, 310 Appendix. C Special Notices, 311 Appendix D Related Publications, 315 International Technical Support Organization Publications, 315 Redbooks on CD-ROMs, 315 Other Publications, 316

10 Contents How To Get ITSO Redbooks, 317 How IBM Employees Can Get ITSO Redbooks, 317 How Customers Can Get ITSO Redbooks, 318 IBM Redbook Order Form, 320 List of Abbreviations, 321 Index, 325 **