book

Java Network Programming, 4th Edition

by Elliotte Rusty Harold

October 2013

Intermediate to advanced

506 pages

13h 35m

English

O'Reilly Media, Inc.

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About the Fourth EditionOrganization of the BookWho You AreJava VersionsAbout the ExamplesConventions Used in This BookRequest for CommentsUsing Code ExamplesSafari® Books OnlineHow to Contact UsAcknowledgments
NetworksThe Layers of a NetworkThe Host-to-Network LayerThe Internet LayerThe Transport LayerThe Application LayerIP, TCP, and UDPIP Addresses and Domain NamesPortsThe InternetInternet Address BlocksNetwork Address TranslationFirewallsProxy ServersThe Client/Server ModelInternet StandardsIETF RFCsW3C Recommendations
Output StreamsInput StreamsMarking and ResettingFilter StreamsChaining Filters TogetherBuffered StreamsPrintStreamData StreamsReaders and WritersWritersOutputStreamWriterReadersFilter Readers and WritersPrintWriter
Running ThreadsSubclassing ThreadImplementing the Runnable InterfaceReturning Information from a ThreadRace ConditionsPollingCallbacksFutures, Callables, and ExecutorsSynchronizationSynchronized BlocksSynchronized MethodsAlternatives to SynchronizationDeadlockThread SchedulingPrioritiesPreemptionBlockingYieldingSleepingJoining threadsWaiting on an objectFinishThread Pools and Executors
The InetAddress ClassCreating New InetAddress ObjectsCachingLookups by IP addressSecurity issuesGetter MethodsAddress TypesTesting ReachabilityObject MethodsInet4Address and Inet6AddressThe NetworkInterface ClassFactory Methodspublic static NetworkInterface getByName(String name) throws SocketExceptionpublic static NetworkInterface getByInetAddress(InetAddress address) throws SocketExceptionpublic static Enumeration getNetworkInterfaces() throws SocketExceptionGetter Methodspublic Enumeration getInetAddresses()public String getName()public String getDisplayName()Some Useful ProgramsSpamCheckProcessing Web Server Logfiles
URIsURLsRelative URLsThe URL ClassCreating New URLsConstructing a URL from a stringConstructing a URL from its component partsConstructing relative URLsOther sources of URL objectsRetrieving Data from a URLpublic final InputStream openStream() throws IOExceptionpublic URLConnection openConnection() throws IOExceptionpublic final Object getContent() throws IOExceptionpublic final Object getContent(Class[] classes) throws IOExceptionSplitting a URL into Piecespublic String getProtocol()public String getHost()public int getPort()public int getDefaultPort()public String getFile()public String getPath()public String getRef()public String getQuery()public String getUserInfo()public String getAuthority()Equality and ComparisonConversionThe URI ClassConstructing a URIThe Parts of the URIResolving Relative URIsEquality and ComparisonString Representationsx-www-form-urlencodedURLEncoderURLDecoderProxiesSystem PropertiesThe Proxy ClassThe ProxySelector ClassCommunicating with Server-Side Programs Through GETAccessing Password-Protected SitesThe Authenticator ClassThe PasswordAuthentication ClassThe JPasswordField Class
The ProtocolKeep-AliveHTTP MethodsThe Request BodyCookiesCookieManagerCookieStore
Opening URLConnectionsReading Data from a ServerReading the HeaderRetrieving Specific Header Fieldspublic String getContentType()public int getContentLength()public String getContentEncoding()public long getDate()public long getExpiration()public long getLastModified()Retrieving Arbitrary Header Fieldspublic String getHeaderField(String name)public String getHeaderFieldKey(int n)public String getHeaderField(int n)public long getHeaderFieldDate(String name, long default)public int getHeaderFieldInt(String name, int default)CachesWeb Cache for JavaConfiguring the Connectionprotected URL urlprotected boolean connectedprotected boolean allowUserInteractionprotected boolean doInputprotected boolean doOutputprotected boolean ifModifiedSinceprotected boolean useCachesTimeoutsConfiguring the Client Request HTTP HeaderWriting Data to a ServerSecurity Considerations for URLConnectionsGuessing MIME Media TypesHttpURLConnectionThe Request MethodHEADDELETEPUTOPTIONSTRACEDisconnecting from the ServerHandling Server ResponsesError conditionsRedirectsProxiesStreaming Mode
Using SocketsInvestigating Protocols with TelnetReading from Servers with SocketsWriting to Servers with SocketsHalf-closed socketsConstructing and Connecting SocketsBasic ConstructorsPicking a Local Interface to Connect FromConstructing Without ConnectingSocket AddressesProxy ServersGetting Information About a SocketClosed or Connected?toString()Setting Socket OptionsTCP_NODELAYSO_LINGERSO_TIMEOUTSO_RCVBUF and SO_SNDBUFSO_KEEPALIVEOOBINLINESO_REUSEADDRIP_TOS Class of ServiceSocket ExceptionsSockets in GUI ApplicationsWhoisA Network Client Library

Using ServerSocketsServing Binary DataMultithreaded ServersWriting to Servers with SocketsClosing Server SocketsLoggingWhat to LogHow to LogConstructing Server SocketsConstructing Without BindingGetting Information About a Server SocketSocket OptionsSO_TIMEOUTSO_REUSEADDRSO_RCVBUFClass of ServiceHTTP ServersA Single-File ServerA RedirectorA Full-Fledged HTTP Server
Secure CommunicationsCreating Secure Client SocketsChoosing the Cipher SuitesEvent HandlersSession ManagementClient ModeCreating Secure Server SocketsConfiguring SSLServerSocketsChoosing the Cipher SuitesSession ManagementClient Mode
An Example ClientAn Example ServerBuffersCreating BuffersAllocationDirect allocationWrappingFilling and DrainingBulk MethodsData ConversionView BuffersCompacting BuffersDuplicating BuffersSlicing BuffersMarking and ResettingObject MethodsChannelsSocketChannelConnectingReadingWritingClosingServerSocketChannelCreating server socket channelsAccepting connectionsThe Channels ClassAsynchronous Channels (Java 7)Socket Options (Java 7)Readiness SelectionThe Selector ClassThe SelectionKey Class
The UDP ProtocolUDP ClientsUDP ServersThe DatagramPacket ClassThe ConstructorsConstructors for receiving datagramsConstructors for sending datagramsThe get Methodspublic InetAddress getAddress()public int getPort()public SocketAddress getSocketAddress()public byte[] getData()public int getLength()public int getOffset()The setter Methodspublic void setData(byte[] data)public void setData(byte[] data, int offset, int length)public void setAddress(InetAddress remote)public void setPort(int port)public void setAddress(SocketAddress remote)public void setLength(int length)The DatagramSocket ClassThe Constructorspublic DatagramSocket() throws SocketExceptionpublic DatagramSocket(int port) throws SocketExceptionpublic DatagramSocket(int port, InetAddress interface) throws SocketExceptionpublic DatagramSocket(SocketAddress interface) throws SocketExceptionprotected DatagramSocket(DatagramSocketImpl impl) throws SocketExceptionSending and Receiving Datagramspublic void send(DatagramPacket dp) throws IOExceptionpublic void receive(DatagramPacket dp) throws IOExceptionpublic void close()public int getLocalPort()public InetAddress getLocalAddress()public SocketAddress getLocalSocketAddress()Managing Connectionspublic void connect(InetAddress host, int port)public void disconnect()public int getPort()public InetAddress getInetAddress()public InetAddress getRemoteSocketAddress()Socket OptionsSO_TIMEOUTSO_RCVBUFSO_SNDBUFSO_REUSEADDRSO_BROADCASTIP_TOSSome Useful ApplicationsSimple UDP ClientsUDPServerA UDP Echo ClientDatagramChannelUsing DatagramChannelOpening a socketReceivingSendingConnectingReadingWritingClosingSocket Options // Java 7
MulticastingMulticast Addresses and GroupsClients and ServersRouters and RoutingWorking with Multicast SocketsThe ConstructorsCommunicating with a Multicast GroupJoining groupsLeaving groups and closing the connectionSending multicast dataLoopback modeNetwork interfacesTwo Simple Examples

Content preview from Java Network Programming, 4th Edition

Chapter 5. URLs and URIs

In the last chapter, you learned how to address hosts on the Internet via host names and IP addresses. In this chapter, we increase the granularity by addressing resources, any number of which may reside on any given host.

HTML is a hypertext markup language because it includes a way to specify links to other documents identified by URLs. A URL unambiguously identifies the location of a resource on the Internet. A URL is the most common type of URI, or Uniform Resource Identifier. A URI can identify a resource by its network location, as in a URL, or by its name, number, or other characteristics.

The URL class is the simplest way for a Java program to locate and retrieve data from the network. You do not need to worry about the details of the protocol being used, or how to communicate with the server; you simply tell Java the URL and it gets the data for you.

URIs

A Uniform Resource Identifier (URI) is a string of characters in a particular syntax that identifies a resource. The resource identified may be a file on a server; but it may also be an email address, a news message, a book, a person’s name, an Internet host, the current stock price of Oracle, or something else.

A resource is a thing that is identified by a URI. A URI is a string that identifies a resource. Yes, it is exactly that circular. Don’t spend too much time worrying about what a resource is or isn’t, because you’ll never see one anyway. All you ever receive from a server is a representation ...