Mastering JXTA : building Java peer-to-peer applications

494 Pages·2002·1.538 MB·English

by  Joe Gradecki

Mastering JXTA
Building Java Peer-to-Peer Applications
Joseph D. Gradecki
Wiley Publishing, Inc.
Publisher: Robert Ipsen Copyeditor: Elizabeth Welch
Editor: Robert M. Elliott Proofreader: Nancy Sixsmith
Managing Editor: John Atkins Compositor: Gina Rexrode
Book Packaging: Ryan Publishing Group, Inc. Technical Editor: Stan Ng
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Library of Congress Cataloging-in-Publication Data:
ISBN: 0-471-25084-8
Printed in the United States of America
10 9 8 7 6 5 4 3 2 1
CO NTE NTS
Part I JXTA Overview
Chapter 1 Introduction to Peer-to-Peer 1
What Is a Peer-to-Peer Architecture? 2
The Hierarchical Topology 3
The Ring Topology 4
The Client-Server, or Centralized, Topology 4
The Decentralized Topology 4
The Hybrid Topology 5
Examples of Peer-to-Peer Systems 6
Napster 6
Gnutella 7
Morpheus/KaZaA 8
Usenet 9
Instant Messaging 10
Extreme Peer-to-Peer: Distributed Computational Engines 10
Warnings 11
Workplace Policies 11
Intellectual Property 11
Bandwidth Costs 12
Security 12
Summary 13
Chapter 2 An Overview of JXTA 15
The JXTA Architecture 17
The Core Layer 17
The Services Layer 18
The Application Layer 18
Major JXTA Technologies 19
IDs 19
The Peer 24
Peer Groups 25
Advertisements 26
Modules 27
Transport Mechanisms and Pipes 28
Services 30
Discovery 31
Handling Private Networks 36
Summary 38
Chapter 3 JXTA Shell 39
Executing the Shell 39
Shell Commands 40
Writing New Shell Commands 53
Summary 53
Chapter 4 Using myJXTA 55
Downloading myJXTA 56
Executing myJXTA 56
Executing myJXTA for the First Time 56
myJXTA Window 59
Summary 72
Chapter 5 JXTA Advertisements 73
Core Advertisements 73
An XML-Based Format 74
Peer Advertisements 75
Peer Group Advertisements 79
Module Class Advertisements 80
Module Specification Advertisements 81
Module Implementation Advertisements 83
Pipe Advertisements 89
Displaying an Advertisement 90
Creating an Advertisement 91
Building an Advertisement from Scratch 92
Summary 93
Part II JXTA Protocols
Chapter 6 Peer Discovery Protocol 95
PDP Protocol Overview 96
Java Binding of the PDP 99
Discovery Service 99
Summary 108
Chapter 7 Peer Resolver Protocol 109
An Overview of the PRP 109
Handler Naming 110
Resolver Query Messages 111
Resolver Response Messages 112
Java Binding of the PRP 115
Building a Handler 116
Getting the Resolver and Registering a Handler 120
Sending a Query 120
Summary 121
Chapter 8 Peer Information Protocol 123
An Overview of the PIP 123
PIP Query Messages 124
PIP Response Messages 124
Java Binding of the PIP 126
Requesting Peer Information 127
Building a Listener 127
Viewing the Information Returned 128
Summary 129
Chapter 9 Peer Endpoint Protocol 131
An Overview of the Peer Endpoint Protocol 131
Endpoint Service 132
Sending a Message 133
Endpoint Protocols 133
Java Binding of the Peer Endpoint Protocol 134
Summary 136
Chapter 10 Pipe Binding Protocol 137
Overview of the Pipe Binding Protocol 137
Pipe Advertisements 138
Pipe Binding Query Messages 138
Java Binding 140
Creating a Pipe 141
Receiving Information 142
Building the Pipe 143
Advertising the Pipe 143
Discovering an Input Pipe 144
Summary 144
Chapter 11 Rendezvous Protocol 145
Rendezvous Advertisements 146
Message Propagation 146
The Java Binding 147
Dynamic Rendezvous Service Implementation 147
Finding Rendezvous Peers Dynamically 148
Connecting to Rendezvous Peers 148
Disconnecting from a Rendezvous Peer 149
Summary 150
Chapter 12 Developing a JXTA Application 151
The Basic Structure for JXTA Applications 152
Connecting to the JXTA Network 153
Viewing Peer Group Information 154
Viewing Peer Group Advertisement 155
Building a Peer to Offer Services 157
Obtaining Group Services 162
Building and Publishing the Module Class Advertisement 163
Building the Pipe Advertisement 164
Building and Publishing the Module Specification Advertisement 166
Waiting for Messages 167
Putting It All Together 168
Building a Peer for Using Services 169
Code for the Receiver Peer 170
Getting Services 175
Finding the Advertisement through Discovery 175
Building an Output Pipe 176
Sending a Message through a Pipe 177
Application Basics 177
Creating a New Peer Group 178
Creating a Peer Group ID 178
Creating a Module Implementation Advertisement 179
Creating a Group Advertisement 180
Creating a New Peer Group 180
A Peer that Discovers and Joins a New Peer Group 187
Creating a Secure Peer Group 192
Using a Membership Service Implementation 192
Changing the Default Class Implementation Advertisement 193
Code for a Secure Peer Group 194
A Secure Peer Group Advertisement 201
Becoming Authenticated 202
New Class Implementation Advertisement Details 204
Peer Group Advertisement Details 205
authenticateMe() Method Details 206
Client for the Secure Peer Group 207
Summary 207
Chapter 13 JXTA Pipes 209
Publishing and Discovering Pipes 210
Publishing 210
Discovery 210
Unicast Pipes 214
Unicast Pipes on a Local Peer 214
Remote Peers 216
UnicastSecure Pipes 218
Propagate Pipes 218
Bidirectional Pipes 225
The Bidirectional Pipe Code 225
The Bidirectional Pipe Discovery Code 229
Reliable Pipes 234
Sender Code 237
The Receiver Code 242
Summary 242
Part III JXTA Implementation
Chapter 14 Content Sharing and the Content Management Service (CMS) 243
Overview of the CMS 243
Implementing the CMS in Peers 245
Initializing the CMS 250
Sharing Content 250
Viewing the Shared Content List 251
Searching For and Getting Content 251
Summary 254
Chapter 15 Implementing Security 255
JXTA Security Toolkit 255
Building Keys 256
Secure Membership Service 263
Building a New Membership Service 264
Changing the Peer Group Creator Code 275
Secure Transport 277
JxtaUnicastSecure Pipes 277
Separately Encrypted Data 279
Summary 300
Chapter 16 Peer Monitoring and Metering 301
Finding Peers in a Group 301
Building the Peer Discovery Listener 301
Interpreting Events 302
The Discovery Code 304
Local Peers versus Remote Peers 305
Obtaining Information about a Peer 307
A Sample Application for Discovering Peers 309
Explaining the Code 315
Code Output 316
Summary 317
Chapter 17 Configuring NAT and Firewall Peers 319
The JXTA Network Topology 319
Running a Peer Behind a Firewall/NAT 320
Communication Peer Configuration 320
Gateway Configuration 323
The Discovery Peer Configuration 324
Using the Configurator’s Debug Option 326
Building a Router/Rendezvous Peer 327
Summary 330
Chapter 18 Using Endpoints for Low-Level Communication 331
The Endpoint Service 331
Code for the Endpoint Receiving Peer 334
Code for the Endpoint Sending Peer 337
Summary 341
Chapter 19 Building a Generic Framework for Distributed Computing 343
Master Code 344
Worker Code 349
Setup 355
Work 355
Computational Code 356
Summary 358
Chapter 20 Building an Encrypted, Highly Available Storage System 359
System Architecture 359
Our Example 361
Database Schema 362
Message Schema 362
Executing the System 363
DatabasePeer 366
DatabasePeer Connectivity 372
Setup 374
Publishing a Data Input Pipe 375
Publishing a Query Bidirectional Pipe 375
Processing Input 375
BusinessPeer 377
Setup 383
Discovery 384
Processing Input 384
GatheringPeers 385
ClientPeer 386
Setup 393
Pipe Discovery 394
The Query Request 395
The Image Request 395
Summary 396
Part IV JXTA Reference
Appendix A Installing JXTA and Compiling JXTA Applications 397
Installing JXTA 397
Easy Install 397
Installing on a Windows System 398
Installing on a Linux System 399
JXTA Libraries 399
Stable Builds 400
Daily Builds 401
Compiling the Examples 401
Windows 401
Linux 402
Running the Examples 402
Windows 402
Linux 403
JBuilder Compiling and Execution 403
Adding a New JBuilder Project 404
Appendix B JXTA API 407
Class Advertisement 407
Field Summary 408
Constructor Summary 408
Method Summary 408
Example 408
Class AdvertisementFactory 408
Method Summary 408
Class AuthenticationCredential 409
Constructor Summary 410
Method Summary 410
Example 410
Class Codat 411
Field Summary 411
Constructor Summary 411
Method Summary 411
Example 411
Class CodatID 412
Constructor Summary 412
Method Summary 412
Example 412
Interface Credential 412
Method Summary 412
Class DiscoveryEvent 413
Constructor Summary 413
Method Summary 413
Example 413
Interface DiscoveryListener 413
Method Summary 414
Example 414
Class DiscoveryQueryMsg 414
Field Summary 414
Constructor Summary 414
Method Summary 414
Class DiscoveryResponseMsg 415
Field Summary 415
Constructor Summary 415
Method Summary 415
Example 416
Interface DiscoveryService 416
Field Summary 416
Method Summary 417
Example 418
Interface Document 418
Method Summary 418
Example 418
Interface Element 419
Method Summary 419
Example 419
Interface EndpointAddress 419
Method Summary 419
Example 420
Class EndpointAdvertisement 420
Constructor Summary 420
Method Summary 420
Interface EndpointFilterListener 421
Method Summary 421
Interface EndpointProtocol 421
Method Summary 421
Example 422
Interface EndpointService 422
Method Summary 422
Example 423
Interface GenericResolver 424
Method Summary 424
Class ID 424
Field Summary 424
Constructor Summary 424
Method Summary 425
Class IDFactory 425
Method Summary 425
Example 426
Interface InputPipe 426
Method Summary 426
Example 426
Class JxtaError 427
Field Summary 427
Constructor Summary 427
Method Summary 427