Java on Solaris 7 Developer’s Guide Sun Microsystems, Inc. 901 San Antonio Road Palo Alto, CA 94303-4900 U.S.A. Part No: 805-4031–10 October, 1998 Copyright 1998 Sun Microsystems, Inc. 901 San Antonio Road, Palo Alto, California 94303-4900 U.S.A. All rights reserved. This product or document is protected by copyright and distributed under licenses restricting its use, copying, distribution, and decompilation. No part of this product or document may be reproduced in any form by any means without prior written authorization of Sun and its licensors, if any. Third-party software, including font technology, is copyrighted and licensed from Sun suppliers. Parts of the product may be derived from Berkeley BSD systems, licensed from the University of California. UNIX is a registered trademark in the U.S. and other countries, exclusively licensed through X/Open Company, Ltd. 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CETTE PUBLICATION EST FOURNIE “EN L’ETAT” ET AUCUNE GARANTIE, EXPRESSE OU IMPLICITE, N’EST ACCORDEE, Y COMPRIS DES GARANTIES CONCERNANT LA VALEUR MARCHANDE, L’APTITUDE DE LA PUBLICATION A REPONDRE A UNE UTILISATION PARTICULIERE, OU LE FAIT QU’ELLE NE SOIT PAS CONTREFAISANTE DE PRODUIT DE TIERS. CE DENI DE GARANTIE NE S’APPLIQUERAIT PAS, DANS LA MESURE OU IL SERAIT TENU JURIDIQUEMENT NUL ET NON AVENU. Please Recycle Contents Preface v 1. Introduction 1 Java And The Java Runtime Environment (JRE) 1 Java 1 JRE 2 JVM 3 The Sun Just-In-Time(JIT) Compiler 5 2. Multithreading 9 Definition Of Multithreading* 9 Java Threads In The Solaris Environment - Earlier Releases* 9 Multithreading Concepts* 10 Benefits of Multithreading* 10 Multithreading Models 11 Many-to-One Model (Green Threads) 12 One-to-One Model 13 Many-to-Many Model (Java on Solaris —Native Threads) 14 The MT Kernel 15 Advantages of Java MT On Solaris 16 Grouping Threads 18 Contents iii Java Threads Issues 19 Generic Java Issues 19 Solaris-Specific Issues 19 3. The Java Programming Environment 21 Java Programs 22 An Application 23 An Applet 23 javald and Relocatable Applications 24 Programming Compute-Bound, Parallellized Java Applications 25 thr_setconcurrency(3T) Example 25 API Mapping 27 Thread Group Methods 29 Java Development Tools 30 Java WorkShopTM (JWS) 30 4. Deprecated Methods 33 What Is Deprecation?* 33 Deprecated Threads Methods 38 5. Application Performance Tuning 43 Tuning Techniques 43 System Interface Level 43 iv Java on Solaris 7 Developer’s Guide ♦ October, 1998 Preface The Java On Solaris 7 Developer’s Guide gives JavaTM developers information about using Java in the SolarisTM 2.6 and Solaris 7 environments. This information includes overviews and descriptions of the important components of Java on Solaris software, their benefits for developers, and how to use Java on Solaris software to get the best application performance. In addition, this document covers compatibility issues. Who Should Use This Book This book is intended primarily for these audiences: Developers who are new to Java on Solaris software Developers new to Java. Information for this audience will be starred(*). How This Book Is Organized Chapter 1, "Introduction", is an overview of subjects covered in this book. Chapter 2, "Multithreading", discusses the basics of multithreading, and the benefits of using the native-threaded Java Virtual Machine (JVM) on Solaris. Chapter 3, "The Java Programming Environment", describes this environment with information specific to using Java on multithreaded Solaris. Chapter 4, "Deprecated Methods", lists those methods that have been deprecated as of Java Development Kit (JDKTM 1.1). Preface v Chapter 5, "Application Performance Tuning", describes ways in which Java developers can increase their applications’ performance. Related Documentation For up-to-date information about Java on Solaris software, refer to www.sun.com/solaris/java For information about Java coding style, see dp-websvr.eng.sun.com/products/jpt/ Ordering Sun Documents The SunDocsSM program provides more than 250 manuals from Sun MicrosystemsTM . If you live in the United States, Canada, Europe, or Japan, you can purchase documentation sets or individual manuals using this program. For a list of documents and how to order them, see the catalog section of SunExpressTM Internet site at http://www.sun.com/sunexpress. What Typographic Changes Mean Table P–1 describes the typographic changes used in this book. vi Java on Solaris 7 Developer’s Guide ♦ October, 1998 TABLE P–1 Typographic Conventions Typeface or Meaning Example Symbol AaBbCc123 The names of commands, Edit your .login file. files, and directories; Use ls -a to list all files. on-screen computer output machine_name% You have mail. AaBbCc123 What you type, contrasted machine_name% su with on-screen computer Password: output AaBbCc123 Command-line placeholder: To delete a file, type rm filename. replace with a real name or value AaBbCc123 Book titles, new words or Read Chapter 6 in User’s Guide. These terms, or words to be are called class options. emphasized You must be root to do this. Shell Prompts in Command Examples Table P–2 shows the default system prompt and superuser prompt for the C shell, Bourne shell, and Korn shell. TABLE P–2 Shell Prompts Shell Prompt C shell prompt machine_name% C shell superuser prompt machine_name# Bourne shell and Korn shell prompt $ Bourne shell and Korn shell superuser prompt # vii viii Java on Solaris 7 Developer’s Guide ♦ October, 1998 CHAPTER 1 Introduction This Developer’s Guide describes features of and information about application development using Java in the Solaris 2.6 and Solaris 7 environments. Note - For important information about this release of Java on Solaris software, refer to http://www.sun.com/solaris/java/ Java And The Java Runtime Environment (JRE) This section describes basic information about Java and the JRE. Java Java is a recently-developed, concurrent, class-based, object-oriented programming and runtime environment, comprised of: A programming language An API specification A virtual machine specification Java has the following characteristics: Object-oriented. Java provides the basic object technology of C++ with some enhancements and some deletions. 1 Architecture-neutral. Java source code is compiled into architecture-independent object code. The object code is interpreted by a Java Virtual Machine (JVM) on the target architecture. Portable. Java implements additional portability standards. For example, intsare always 32-bit, 2’s-complemented integers. User interfaces are built through an abstract window system that is readily implemented in Solaris and other operating environments.