Table Of ContentTCP/IP Sockets in Java
Second Edition
The Morgan Kaufmann Practical Guides Series
Series Editor: Michael J. Donahoo
TCP/IPSocketsinJava:PracticalGuideforProgrammers,SecondEdition
KennethL.CalvertandMichaelJ.Donahoo
SQL:PracticalGuideforDevelopers
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C#2.0:PracticalGuideforProgrammers
MicheldeChamplainandBrianPatrick
Multi-TierApplicationProgrammingwithPHP:PracticalGuideforArchitectsandProgrammers
DavidWall
TCP/IPSocketsinC#:PracticalGuideforProgrammers
DavidMakofske,MichaelJ.Donahoo,andKennethL.Calvert
JavaCryptographyExtensions:PracticalGuideforProgrammers
JasonWeiss
JSP:PracticalGuideforProgrammers
RobertBrunner
JSTL:PracticalGuideforJSPProgrammers
SueSpielman
Java:PracticalGuideforProgrammers
MichaelSikora
MulticastSockets:PracticalGuideforProgrammers
DavidMakofskeandKevinAlmeroth
TheStrutsFramework:PracticalGuideforJavaProgrammers
SueSpielman
TCP/IPSocketsinC:PracticalGuideforProgrammers
KennethL.CalvertandMichaelJ.Donahoo
JDBC:PracticalGuideforJavaProgrammers
GregorySpeegle
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TCP/IP Sockets in Java
Practical Guide for Programmers
Second Edition
Kenneth L. Calvert
UniversityofKentucky
Michael J. Donahoo
BaylorUniversity
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TCP/IPsocketsinJava:practicalguideforprogrammers/KennethL.Calvert,MichaelJ.
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ISBN978-0-12-374255-1(pbk.:alk.paper)1.Internetprogramming.2.TCP/IP(Computernetwork
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Contents
Preface xi
1 Introduction 1
1.1 Networks,Packets,andProtocols 1
1.2 AboutAddresses 4
1.3 AboutNames 6
1.4 ClientsandServers 6
1.5 WhatIsaSocket? 7
1.6 Exercises 8
2 BasicSockets 9
2.1 SocketAddresses 9
2.2 TCPSockets 15
2.2.1 TCPClient 16
2.2.2 TCPServer 21
2.2.3 InputandOutputStreams 25
2.3 UDPSockets 26
2.3.1 DatagramPacket 27
2.3.2 UDPClient 29
2.3.3 UDPServer 34
2.3.4 SendingandReceivingwithUDPSockets 36
2.4 Exercises 38
3 SendingandReceivingData 39
3.1 EncodingInformation 40
3.1.1 PrimitiveIntegers 40
vii
viii
Contents
3.1.2 StringsandText 45
3.1.3 Bit-Diddling:EncodingBooleans 47
3.2 ComposingI/OStreams 48
3.3 FramingandParsing 49
3.4 Java-SpecificEncodings 55
3.5 ConstructingandParsingProtocolMessages 55
3.5.1 Text-BasedRepresentation 58
3.5.2 BinaryRepresentation 61
3.5.3 SendingandReceiving 63
3.6 WrappingUp 71
3.7 Exercises 71
4 BeyondtheBasics 73
4.1 Multitasking 73
4.1.1 JavaThreads 74
4.1.2 ServerProtocol 76
4.1.3 Thread-per-Client 80
4.1.4 ThreadPool 82
4.1.5 System-ManagedDispatching:TheExecutorInterface 84
4.2 BlockingandTimeouts 86
4.2.1 accept(),read(),andreceive() 87
4.2.2 ConnectingandWriting 87
4.2.3 LimitingPer-ClientTime 87
4.3 MultipleRecipients 89
4.3.1 Broadcast 90
4.3.2 Multicast 90
4.4 ControllingDefaultBehaviors 95
4.4.1 Keep-Alive 96
4.4.2 SendandReceiveBufferSize 96
4.4.3 Timeout 97
4.4.4 AddressReuse 97
4.4.5 EliminatingBufferingDelay 98
4.4.6 UrgentData 98
4.4.7 LingeringafterClose 99
4.4.8 BroadcastPermission 99
4.4.9 TrafficClass 100
4.4.10 Performance-BasedProtocolSelection 100
4.5 ClosingConnections 101
4.6 Applets 107
4.7 WrappingUp 107
4.8 Exercises 108
5 NIO 109
5.1 WhyDoWeNeedThis? 109
5.2 UsingChannelswithBuffers 112
ix
Contents
5.3 Selectors 115
5.4 BuffersinDetail 121
5.4.1 BufferIndices 121
5.4.2 BufferCreation 122
5.4.3 StoringandRetrievingData 124
5.4.4 PreparingBuffers:clear(),flip(),andrewind() 126
5.4.5 CompactingDatainaBuffer 128
5.4.6 BufferPerspectives:duplicate(),slice(),etc. 129
5.4.7 CharacterCoding 131
5.5 Stream(TCP)ChannelsinDetail 132
5.6 SelectorsinDetail 135
5.6.1 RegisteringInterestinChannels 135
5.6.2 SelectingandIdentifyingReadyChannels 138
5.6.3 ChannelAttachments 140
5.6.4 SelectorsinaNutshell 140
5.7 Datagram(UDP)Channels 141
5.8 Exercises 145
6 UndertheHood 147
6.1 BufferingandTCP 150
6.2 DeadlockDanger 152
6.3 PerformanceImplications 155
6.4 TCPSocketLifeCycle 155
6.4.1 Connecting 156
6.4.2 ClosingaTCPConnection 160
6.5 DemultiplexingDemystified 163
6.6 Exercises 165
Bibliography 167
Index 169
