Tài liệu java Data Access JDBC, JNDI, and JAXP pptx

Java Data Access—JDBC, JNDI, and JAXP Todd M. Thomas Published by M&T Books An imprint of Hungry Minds, Inc. 909 Third Avenue New York, NY 10022 http://www.hungryminds.com/ Copyright © 2002 Hungry Minds, Inc. All rights reserved. No part of this book, including interior design, cover design, and icons, may be reproduced or transmitted in any form, by any means (electronic, photocopying, recording, or otherwise) without the prior written permission of the publisher. Library of Congress Control Number: 2001092891 ISBN: 0-7645-4864-8 Printed in the United States of America 10 9 8 7 6 5 4 3 2 1 1O/RR/QR/QS/IN Distributed in the United States by Hungry Minds, Inc. Distributed by CDG Books Canada Inc. for Canada; by Transworld Publishers Limited in the United Kingdom; by IDG Norge Books for Norway; by IDG Sweden Books for Sweden; by IDG Books Australia Publishing Corporation Pty. 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For press review copies, author interviews, or other publicity information, please contact our Public Relations department at 317-572-3168 or fax 317-572-4168. For authorization to photocopy items for corporate, personal, or educational use, please contact Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, or fax 978-750-4470. Trademarks: Hungry Minds, the Hungry Minds logo, M&T Books, the M&T Books logo, and Professional Mindware are trademarks or registered trademarks of Hungry Minds, Inc., in the United States and other countries and may not be used without written permission. Java and JDBC are trademarks or registered trademarks of Sun Microsystems, Inc. All other trademarks are the property of their respective owners. Hungry Minds, Inc., is not associated with any product or vendor mentioned in this book. Credits Acquisitions Editor Grace Buechlein Project Editor Michael Koch Technical Editor Terry Smith Copy Editor S. B. 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NEITHER THE PUBLISHER NOR AUTHOR SHALL BE LIABLE FOR ANY LOSS OF PROFIT OR ANY OTHER COMMERCIAL DAMAGES, INCLUDING BUT NOT LIMITED TO SPECIAL, INCIDENTAL, CONSEQUENTIAL, OR OTHER DAMAGES. Vice President and Publisher Joseph B. Wikert Project Coordinator Nancee Reeves Graphics and Production Specialists Sean Decker Melanie DesJardins Laurie Petrone Jill Piscitelli Betty Schulte Jeremey Unger Quality Control Technicians Laura Albert David Faust John Greenough Andy Hollandbeck Angel Perez Proofreading and Indexing TECHBOOKS Production Services Cover Image © Noma/Images.com About the Author Todd M. Thomas is an Oracle Certified DBA and Java developer with more than six years’ experience in the IT industry. He currently works as an independent consultant, software developer, and trainer focusing on Java database and network programming. His work has ranged from building and managing data warehouses to architecting enterprise Java server applications. His most recent assignment was helping develop the network and database interface layers for BlueMoon, Airtuit Inc.’s wireless application gateway. His education includes a B.S. in Industrial Engineering and an M.S. in Engineering Science from the University of Tennessee in Knoxville. About the Contributors Johennie Helton has been an architect, developer, and software consultant on numerous n-tier– distributed systems and products. She has worked with databases and database design and implementation since 1990. Her database design projects include an application to make available automobile inventory online, a material management application for the health-care industry, and an application for customer coupon redemption for the grocery and coupon industries. During her career, her focus has been on creating applications with leading-edge technology, including application modeling, database design and implementation, and using J2EE and Java technologies to provide enterprise solutions to customers. She has a strong background in object-oriented analysis and design as well as in hypermedia systems. She has an M.S. in Computer Science from the University of Colorado. Steve Nobert got his first taste of programming in 1983, when he took a mathematics class in his senior year in high school. The class entailed developing computer programs on an Apple IIe to solve math problems. He hasn’t looked back since. As much as Steve loathed school, he still went on to receive his Associate of Science degree from Northern Virginia Community College in 1988, his Bachelor of Science degree from James Madison University in 1990, and his Master of Science degree from George Mason University in 1996, all of them in Computer Science. He has more than twelve years of professional programming experience involving myriad heterogeneous computing languages, operating systems, and state-of-the-art technologies. Steve’s primary career focus has been developing GUI applications on various flavors of UNIX. In 1996, Steve recommended that an unmaintainable and internationalized cross-platform application be rewritten using Java technology. He taught himself Java to develop the application/applet, and Java technology instantly became his primary career focus and has been so ever since. He has been involved in database technology since 1990. Steve has lived most of his life overseas and then in the northern Virginia area for almost fifteen years. Steve and his wife, Misti, reside in Knoxville, Tennessee. Table of Contents Part I: Getting Started with Java Data Access 1 Chapter List 1 Chapter 1: Introducing Java Data Access Development .2 In This Chapter 2 Taking Stock of Enterprise Data Stores .2 Database systems 4 Naming and directory services .5 XML services 6 Introducing Java Data Access Technologies .6 JDBC 3.0 .7 JNDI 8 JDO .9 Java XML APIs 10 Summary 10 Chapter 2: A Relational Database Primer 12 In This Chapter 12 The RDBMS in a Nutshell .12 Understanding data storage .14 Ensuring data integrity 15 Reviewing SQL Basics 19 Using Data Manipulation Language (DML) 20 Using Data Definition Language (DDL) 25 Summary 28 Part II: Understanding JDBC Programming Basics .29 Chapter List 29 Chapter 3: Setting Up Your First JDBC Query 30 In This Chapter 30 Configuring JDBC .30 Obtaining JDBC drivers 31 Installing the JDBC driver 31 Examining the Common JDBC Components 32 Writing Your First JDBC Application .33 Creating the sample application 33 Compiling and running the application 41 Troubleshooting the sample application .42 Summary 43 Chapter 4: Connecting to Databases with JDBC .44 In This Chapter 44 Understanding JDBC Drivers 44 What are JDBC drivers? .46 Using your JDBC driver .49 Working with Connection Objects .53 Understanding JDBC URLs 53 i Table of Contents Chapter 4: Connecting to Databases with JDBC Opening connections .54 Closing JDBC connections .57 Summary 58 Chapter 5: Building JDBC Statements .59 In This Chapter 59 Using JDBC Statements .59 Introducing Statement Objects .60 Creating the Statement object .61 Using the Statement object .61 JDBC batch processing .70 JDBC transactions .72 Closing the Statement object 76 Working with PreparedStatement Objects .76 Creating the PreparedStatement object .77 Using the PreparedStatement object .77 Working with CallableStatement Objects 83 Creating the CallableStatement object 83 Using the CallableStatement object 84 Summary 87 Chapter 6: Working with Result Sets .88 In This Chapter 88 What Are JDBC Result Sets? 88 Introducing Result Set Concepts 89 Result set cursors 89 Result set types .90 Retrieving result set data .91 Using Standard Result Sets 93 Creating a standard result set 93 Moving data around in a standard result set .94 Using Scrollable Result Sets 96 Creating scrollable result sets .97 Moving around scrollable result sets 98 Using Updateable Result Sets 103 Creating updateable result sets .104 Updating data with updateable result set 105 Inserting and deleting data with updateable result sets .108 Summary 109 Chapter 7: Understanding JDBC Data Types 110 In This Chapter 110 Java, Databases, and Data Types .110 Java−to−JDBC Data−Type Mappings .111 JDBC−to−Java Data−Type Mappings .114 Standard SQL data types .114 Advanced SQL data types .118 ii Table of Contents Chapter 7: Understanding JDBC Data Types Custom Data Type Mapping 128 Building custom data type maps .128 Using custom mapping .131 Summary 133 Chapter 8: Mining Database Metadata with JDBC 134 In This Chapter 134 The JDBC Metadata Interfaces 134 The ResultSetMetaData Interface 135 Creating ResultSetMetaData objects 135 Using ResultSetMetaData objects 135 ResultSetMetaData example .136 The DatabaseMetaData Interface .140 Creating DatabaseMetaData objects .141 Using DatabaseMetaData objects .141 DatabaseMetaData example .144 Summary 149 Part III: Using Java Data Access Design Patterns .150 Chapter List 150 Chapter 9: Understanding Design Patterns .151 In This Chapter 151 What Are Design Patterns? 151 Categories of Design Patterns 152 Creational patterns 152 Structural patterns .154 Behavioral patterns .154 Java and Design Patterns .156 Inheritance 156 Composition 159 Design−pattern implementation guidelines 161 Summary 162 Chapter 10: Building the Singleton Pattern .163 In This Chapter 163 What Is a Singleton Pattern? 163 Structure of the Singleton Pattern 164 Using the Singleton Pattern .165 Basic Singleton example .165 Connection manager Singleton example 168 Summary 172 Chapter 11: Producing Objects with the Factory Method Pattern 174 In This Chapter 174 What Is the Factory Method Pattern? 174 Introducing the Factory Method Structure .175 iii Table of Contents Chapter 11: Producing Objects with the Factory Method Pattern Using the Factory Method .176 Summary 187 Chapter 12: Creating a Façade Pattern 188 In This Chapter 188 What Is the Façade Pattern? .188 Introducing the Structure of the Façade Pattern 189 Implementing the Façade Pattern .189 Summary 202 Part IV: Taking It to the Enterprise .203 Chapter List 203 Chapter 13: Accessing Enterprise Data with JNDI .204 In This Chapter 204 Naming and Directory Services .204 Naming services 205 Directory services .206 Data Access with JNDI 208 JNDI architecture 209 JNDI programming .211 Working with the JNDI LDAP SPI 214 Summary 223 Chapter 14: Using Data Sources and Connection Pooling 224 In This Chapter 224 Working with Java DataSource Objects 224 Using DataSource objects .225 Looking at DataSource implementations 226 A DataSource example .227 Using DataSource objects with JNDI .228 Implementing Connection Pooling 231 Understanding connection−pooling concepts .232 A connection−pooling example 232 Summary 234 Chapter 15: Understanding Distributed Transactions 235 In This Chapter 235 Understanding the Basics .235 Transaction definition and properties .235 Two−phase commit 236 Transaction−processing performance and availability .236 Replication 237 Understanding Distributed Transactions 238 Understanding the Transaction Monitor .238 Understanding the Transaction Service 239 Distributed Transactions and Java .242 iv Table of Contents Chapter 15: Understanding Distributed Transactions EIS and EAI 243 JMS .244 JTS and JTA 244 EJBs 245 Summary 247 Chapter 16: Working with JDBC Rowsets .248 In This Chapter 248 Introducing JDBC Rowsets .248 Understanding Rowset Concepts .249 Rowset implementations .249 Examining the rowset architecture .250 Working with RowSet Objects 251 Setting rowset properties 253 Configuring rowset events 253 Setting rowset connection properties 254 Executing SQL commands using rowsets 255 Fetching data from a rowset 256 Traversing data in a rowset .256 Controlling scrollable and updateable properties .257 Setting transaction levels 257 Cleaning up after a RowSet 258 Using the JdbcRowSet Class .258 Using the CachedRowSet Class .260 Serializing a CachedRowSet object 261 Updating and inserting disconnected rowset data .264 Using the WebRowSet Class .265 Summary 269 Chapter 17: Building Data−centric Web Applications 271 In This Chapter 271 Reviewing Enterprise Web Applications .271 Two−tier Web architecture .272 MVC design pattern 273 Three−tier Web architecture .273 n−tier Web architecture 274 J2EE enterprise application framework 275 Using JDBC with Servlets .276 Servlet overview .276 Constructing a JDBC servlet .277 Server deployment 283 Design considerations .284 Using JDBC with JavaServer Pages 286 JSP overview .286 Constructing a JSP page .287 Using JDBC in JSP pages .290 Using JSP with JDBC JavaBeans .299 v [...]... with Java Data Access Chapter List Chapter 1: Introducing Java Data Access Development Chapter 2: A Relational Database Primer 1 Chapter 1: Introducing Java Data Access Development In This Chapter • Understanding how enterprises use and store data • Using the Java technologies for accessing the different enterprise data stores Now more than ever, Java developers need to understand how to create data ... that help you access the different types of data stores Figure 1−2 shows the role Java Data Access Technologies (JDATs) play in the enterprise environment 6 Chapter 1: Introducing Java Data Access Development From the figure you can see that JDAT includes JDBC, JNDI, JDO, and the XML APIs You use the JDBC API to access data stored in a SQL database The JNDI API gives you access to naming and directory... use the API to access relational databases without involving J2EE The remaining sections provide more details on the different Java data access technologies shown in Figure 1−2 Figure 1−2: The role Java Data Access Technologies (JDATs) play in the enterprise environment JDBC 3.0 JDBC, the Java database access technology, is probably the most widely known Java data access API Many books and Web sites... relational databases • Naming and directory services such as RMI Registries and LDAP−enabled directory services • XML documents containing self−describing data from databases or used in inter−application communication To help you access the various types of data storage containers in the previous list, Java provides the following data access technologies: 10 Chapter 1: Introducing Java Data Access Development... relational databases, with naming and directory services you cannot easily model processes or protect data using integrity constraints Naming and directory services also lack a common data access language like SQL and you usually rely on a vendor’s API for access Fortunately, Java s JNDI API addresses this lack of a standard access method by providing a common interface to many different naming and directory... limited power supplies, and intermittent network access Fortunately, Java provides a robust set of data access technologies that enables you to access the most common types of enterprise data Using these same technologies you can create both server−side components and client−side applications The technologies consist of APIs for accessing databases, naming and directory services, and XML documents This... object databases support object−oriented programming concepts such as inheritance, polymorphism, and encapsulation of the user−defined data types Some support SQL while others have proprietary access languages • Object−relational database — A cross between an object database and a relational database Most often, object−relational databases are relational databases that treat objects as new data types... as data updates and backups more frequently and reliably Today’s databases can store more than just simple character or numerical data The Internet has pushed database vendors to support more varied forms of data For example, most database systems now enable you to store multimedia data such as sound and video In addition, support for persisting native programming objects, such as those used by Java, ... naming and directory services provide you with a powerful tool for retrieving data In addition, they are useful when you do not need the overhead of hardware and DBAs to run a relational database 5 Chapter 1: Introducing Java Data Access Development XML services The eXtensible Markup Language (XML) enables you to create self−documenting data Enterprises now use XML as the standard for exchanging data and. .. for accessing relational databases • JNDI 1.2, which provides support for interacting with naming and directory services • JDO, which enables you to easily persist Java objects in a variety of data stores • XML APIs, which consist of JAXP, JAX−RPC, JAXM, JAXB, and JAXR, and that enable you to parse, send, and transform XML document 11 Chapter 2: A Relational Database Primer In This Chapter • Understanding . with Java Data Access Chapter List Chapter 1: Introducing Java Data Access Development Chapter 2: A Relational Database Primer 1 Chapter 1: Introducing Java. includes JDBC, JNDI, JDO, and the XML APIs. You use the JDBC API to access data stored in a SQL database. The JNDI API gives you access to naming and directory