XML, XML, XML, XML. You can see it on hats and t-shirts, read about it on the cover of every technical magazine on the planet, and hear it on the radio or the occasional Gregorian chant album. . . . Well, maybe it hasn't gone quite that far yet, but don't be surprised if it does. XML, the Extensible Markup Language, has seemed to take over every aspect of technical life, particularly in the Java™ community. An application is no longer considered an enterprise-level product if XML isn't being used somewhere. Legacy systems are being accessed at a rate never before seen, and companies are saving. | and XML O REILLY Team oR 2001 x java Java and XML Java and XML Copyright 2000 O Reilly Associates Inc. All rights reserved. Printed in the United States of America. Published by O Reilly Associates Inc. 101 Morris Street Sebastopol CA 95472. The Java Series is a trademark of O Reilly Associates Inc. Java and all Java-based trademarks and logos are trademarks or registered trademarks of Sun Microsystems Inc. in the United States and other countries. O Reilly Associates Inc. is independent of Sun Microsystems. The O Reilly logo is a registered trademark of O Reilly Associates Inc. Many of the designations used by manufacturers and sellers to distinguish their products are claimed as trademarks. Where those designations appear in this book and O Reilly Associates Inc. was aware of a trademark claim the designations have been printed in caps or initial caps. The association between the image of a Tupperware SHAPE-O and Java and XML is a trademark of O Reilly Associates Inc. SHAPE-O is a registered trademark of Dart Industries Inc. Tupperware Worldwide and is used with permission. While every precaution has been taken in the preparation of this book the publisher assumes no responsibility for errors or omissions or for damages resulting from the use of the information contained herein. 2001 O Reilly Associates Inc. page 2 Preface. 5 Organization. 6 Who Should Read This Book . 8 Software and Versions. 8 Conventions Used in This Book. 9 Comments and Questions. 9 Acknowledgments. 10 Chapter 1. Introduction. 11 What Is It . 12 How Do I Use It . 19 Why Should I Use It . 21 What s Next . 33 Chapter 2. Creating XML. 33 An XML Document. 34 An XML Document. 35 The Content. 36 What s Next . 43 Chapter 3. Parsing XML. 43 Getting Prepared. 43 SAX Readers. 45 Content Handlers. 49 Error Handlers. 64 Error Handlers. 70 Gotcha . 76 What s Next . 79 Chapter 4. Constraining XML. 79 Why Constrain XML Data . 79 Document Type Definitions. 82 XML Schema. 94 What s Next . 106 Chapter 5. .
