Home > Store

JavaSpaces Example by Example

Register your product to gain access to bonus material or receive a coupon.

JavaSpaces Example by Example

  • Published Nov 9, 2001 by Pearson.

Book

  • Sorry, this book is no longer in print.
Not for Sale

Description

  • Copyright 2002
  • Dimensions: K
  • Pages: 288
  • Edition: 1st
  • Book
  • ISBN-10: 0-13-061916-7
  • ISBN-13: 978-0-13-061916-7

  • The hands-on, example-rich guide to JavaSpaces technology
  • Building robust, scalable, high-performance distributed applications
  • Up-to-the-minute coverage based on Jini 1.1 network technology and JDK 1.4 software
  • Practical solutions to the most common challenges of distributed development

The example-rich guide to JavaSpaces technology: building more robust, scalable, and secure distributed applications for working developers!

JavaSpaces technology simplifies distributed computing, by providing a shared virtual space where tasks, requests, and information can easily be exchanged in the form of objects based on Javatm technology. JavaSpaces Example by Example offers an example-rich introduction to JavaSpaces architecture and its Jini network technology-based interfaces. Using this book's extensive examples and projects, experienced developers can begin building applications using the JavaSpaces specification almost immediately—and quickly master advanced techniques for enhancing security, performance, and scalability.

Steven L. Halter begins by introducing JavaSpaces technology: its goals, advantages, applications, and current capabilities. He walks you through obtaining, installing, and configuring JavaSpaces architecture, addressing common problems such as authorization configuration and improper codebase settings. Next, he introduces the fundamental concepts of development, including entries, leasing, events, transactions, and persistence.

You'll learn powerful distributed programming techniques, including the effective use of data structures and collections; and better ways to improve performance, prevent deadlock, and take full advantage of parallelism. Halter provides in-depth coverage of scalability and availability, concluding with detailed guidance on using security features based on Java 2 technology to protect distributed JavaSpaces applications.

Extensive code examples illustrate:

  • Leasing and events
  • Transactions and persistence
  • Jini technology interfaces
  • Performance optimization
  • Data structures
  • Collections
  • Preventing deadlock
  • Maximizing parallelism
  • Distributed application security
  • Improving scalability

Sample Content

Online Sample Chapter

Why Should You Be Using JavaSpaces?

Table of Contents



Preface.

I. GETTING TO KNOW JAVASPACES.

1. About JavaSpaces.

What Is a JavaSpace? JavaSpace Interface. Jini and JavaSpaces. Shared Distributed Computing. Persistent Object Repository. Uses of JavaSpaces. Information Sharing. Compute Serving. Work Flow. What's Next.

2. Obtaining and Installing JavaSpaces.

Getting Java Installed. Getting and Installing Jini. Sun Community Source License (SCSL). Getting Jini. Installing Jini. Getting a JavaSpace Running. Starting the Supporting Services. Starting with the GUI. Starting from the Command Line. Running the Ray-Tracing Example. What's Next.

3. JavaSpaces Basics.

Coding Conventions. Finding a JavaSpace. Compiling. Running the Services. Running the Example. Entries. Writing an Entry. Compiling. Running the Example. Reading an Entry. Entry Templates. Compiling. Running the Example. Taking an Entry. Compiling. Running the Example. The Snapshot Method. What's Next.

4. More JavaSpaces.

Leasing. Using Leases with JavaSpaces. Compiling. Running the Example. Using Transactions with JavaSpaces. Creating a Transaction. Transactions and JavaSpace Methods. Using Transactions with JavaSpaces. Distributed Events. Distributed Events and JavaSpaces. Event Example. Persistence. What's Next.

II. DISTRIBUTED PROGRAMMING.

5. Encouraging Distribution.

Distributed Concepts. Parallelism. Partial Failure. Communication/Synchronization. Distributed Structures. Arrays. Compiling. Running the Example. Queues. Unordered Structures. What's Next.

6. Synchronization Issues.

Types of Synchronization Problems. Data Corruption. Deadlock Problems. Starvation Problems7. Synchronization Methodologies. Basic JavaSpace Mechanisms. Space Initialization. Semaphores. The Music Store Example. Compiling. To compile the classes for the synchronization example in Windows, use the following. What's Next.

7. Fairly Sharing Resources.

Sharing Fairly. Order-Processing Example. Item Viewer. Compiling. Running the Example. What's Next.

III. GOING TO THE NEXT LEVEL.

8. Parallel Computing.

Parallel Computing in General. Splitting Tasks up. Piecing Together the Results. A Parallel Computing Framework. A Prime Number Counter Application. Compiling. Running the Example. Scaling Further. Scaling Further Still. What's Next.

9. Security Issues.

Security in General. Security Model. RMID Security. Policy Files. Service Policies. Client Policy Files. Signing Files. JavaSpaces Security.

10. Wrapping It up.

Useful Places for Information. Web Sites. Mailing Lists. Other Technologies of Interest.

Conclusion.
Index.

Preface

Preface

Writing distributed programs is hard. This should not be a surprising statement to anyone who has had to deal with a distributed programming environment in the past. The good news is that every year it is getting a little bit easier as programming technologies and tools gradually catch up to the needs of a distributed environment. In particular, the introduction of JavaSpaces technology simplifies the distributed computing environment in several ways.

JavaSpaces technology is a simple mechanism for performing distributed computing. In a distributed application, JavaSpaces provides a shared virtual space that providers and requesters of objects can use to communicate easily. This allows for the simple exchange of tasks, requests, and information in the form of Java objects. JavaSpaces also provides the ability to create and store objects with persistence.

JavaSpaces is a Jini technology service. This means that developers working with JavaSpaces can also make use of the various Jini services, such as transactions and notification.

JavaSpaces provides these capabilities with a very simple interface. Effectively making use of the simple interface, however, requires a number of tools, both conceptual and practical. This book should provide a solid base with a coherent set of examples to lead people in the right directions for using JavaSpaces technology.

About This Book

The intended audience is for intermediate to advanced programmers wanting to learn about JavaSpaces. A working knowledge of Java is needed, and an acquaintance with Jini concepts is very useful, but not required.

In this book, I have tried to give complete examples for each of the concepts that are being discussed.

Organization

In Part 1, "Getting to Know JavaSpaces," you look into the basics of using JavaSpaces. In Chapter 1, "About JavaSpaces" you explore what JavaSpaces are, how this book deals with them, and why anyone would want to use them. On the "what" side, the JavaSpace interface is presented along with some definitions of what the interfaces are. On the "why" side, the chapter presents some high level descriptions of the uses of JavaSpaces that are fleshed out in later chapters. Examples include using JavaSpaces as a mechanism for decoupled communication, application structuring, and parallel computing.

In Chapter 2, "Obtaining and Installing JavaSpaces," you get JavaSpaces (and Jini itself) up and running. Doing this the first time can be a challenging experience. This chapter takes you through the process of installing Jini and JavaSpaces and running a simple application. In particular, some of the common problems, such as authorization configuration problems and improper codebase settings, are covered. Although an experienced Jini developer may skip this chapter, for beginners, this should be extremely valuable.

In Chapter 3, "JavaSpaces Basics," you start to explore actually using a JavaSpace and writing some simple programs. It covers a simple method of locating a single JavaSpace. You then look at what an Entry is and how it can be used. Each concept is presented in the context of simple examples at this point.

Chapter 4, "More JavaSpaces," will flesh out the more advanced topics of dealing with JavaSpaces. Again, each of the topics is covered in a simple example format. Later chapters make greater use of these. This chapter is intended to establish familiarity and building blocks for these topics.

In Part 2, "Distributed Programming," you look at how you can apply the basics that you learned in Part 1 into writing distributed applications. In Chapter 5, "Encouraging Distribution," you start to explore programming in a distributed environment. Distributed programming is different than programming within a single machine (process). This chapter covers some of the concepts involved with programming in a distributed environment. In particular, it uses the concept of a linked list to explore some of the differences between distributed and nondistributed data structures.

Chapter 6, "Preventing Deadlock," discusses mechanisms for allowing processes to avoid deadlock. This chapter covers locking and sharing issues and presents mechanisms, such as semaphores, for dealing with resource synchronization.

Chapter 7, "Sharing Fairly," presents a more complex application example that makes use of (and ties together) many of the topics covered in earlier chapters. The application presents a small ordering processing system. This will be used to illustrate the concepts of sharing data in a fair and reliable manner.

In Part 3, "Going to the Next Level," you look at how you can use the mechanisms you learned in Parts 1 and 2 and use these mechanisms to help meet demands that are needed to move into real world applications. Chapter 8, "Parallel Computing," looks into some of the areas where you can get into performance trouble and also some of the ways in which JavaSpaces can be an aid to performance. There are a number of ways to improve (or degrade) the performance of a distributed application. Some common techniques for doing this, such as how to decide what computations could benefit from being distributed and how to distribute data, are discussed in this chapter.

Chapter 9, "Security Issues," looks into some of the security issues around JavaSpaces. There is currently no standard Jini security model. That does not mean, however, that your application can have no security itself. This chapter shows you how some of the security features of Java can be currently used with JavaSpaces. Setting up policy files and using some simple protocols to aid in application level security are discussed.

Chapter 10, "Wrapping It up" ties up any loose ends. In it, you also briefly encounter some of the ways JavaSpaces are being used and might be used.

Updates

Submit Errata

More Information

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.

Overview


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information


To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.

Surveys

Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.

Newsletters

If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information


Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.

Security


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.

Children


This site is not directed to children under the age of 13.

Marketing


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information


If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.

Choice/Opt-out


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information


Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents


California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure


Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.

Links


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact


Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice


We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020