Package xal.extension.service

Class ServiceDirectory

java.lang.Object
xal.extension.service.ServiceDirectory
public final class ServiceDirectory extends Object
ServiceDirectory is a local point of access for registering and looking up services on a network. It wraps the standard Bonjour mechanism to provide a simple way to register and lookup services by using a Java interface as a service name. XML-RPC is the communication protocol used for messaging. Both Bonjour and XML-RPC are accepted protocols implemented in multiple languages.
Author:
tap

  • Field Details

  • Constructor Details

  • Method Details

    • defaultDirectory

      public static ServiceDirectory defaultDirectory()
      Get the default ServiceDirectory instance.
      Returns:
      The default ServiceDirectory instance.

    • dispose

      public void dispose()
      Shutdown bonjour and the RPC server and dispose of all resources.

    • isActive

      public boolean isActive()
      Check if service support is active. If initialization fails, then services will not be active.
      Returns:
      true if services are available

    • isLoopback

      public boolean isLoopback()
      Determine if bonjour is running in loopback mode which would indicate that the computer is isolated from the network. This flag is meaningful only if the service directory is active.
      Returns:
      true if the service is running in loopback mode and false if it is on a network

    • getStandardCodingTypes

      public List<String> getStandardCodingTypes()
      Get a list of standard data types which are supported for coding and decoding

    • getSupportedCodingTypes

      public List<String> getSupportedCodingTypes()
      Get a list of all data types which are supported for coding and decoding

    • registerCodingType

      public <C, R> void registerCodingType(Class<C> type, ConversionAdaptor<C,R> adaptor)
      Register the custom type and its associated adaptor to use for encoding and decoding objects of the custom type
      Parameters:
      type - type to identify and process for encoding and decoding
      adaptor - translator between the custom type and representation constructs

    • registerService

      public <T> ServiceRef registerService(Class<T> protocol, String name, T provider) throws ServiceException
      Register a local service provider.
      Parameters:
      protocol - The protocol identifying the service type.
      name - The unique name of the service provider.
      provider - The provider which handles the service requests.
      Returns:
      a new service reference for successful registration and null otherwise.
      Throws:
      ServiceException

    • registerService

      public <T> ServiceRef registerService(Class<T> protocol, String serviceName, T provider, Map<String,Object> properties)
      Register a local service provider.
      Parameters:
      protocol - The protocol identifying the service type.
      serviceName - The unique name of the service provider.
      provider - The provider which handles the service requests.
      properties - Properties.
      Returns:
      a new service reference for successful registration and null otherwise.

    • unregisterService

      public boolean unregisterService(ServiceRef serviceRef) throws ServiceException
      Unregister a local service.
      Parameters:
      serviceRef - The service reference whose service should be shutdown.
      Returns:
      true if the service has been unregistered and false otherwise.
      Throws:
      ServiceException

    • getProxy

      public <T> T getProxy(Class<T> protocol, ServiceRef serviceRef)
      Get a proxy to the service with the given service reference and protocol.
      Parameters:
      protocol - The protocol implemented by the service.
      serviceRef - The service reference.
      Returns:
      A proxy implementing the specified protocol for the specified service reference

    • lookupService

      public ServiceRef lookupService(String type, String name)
      Lookup the service given the fully qualified service type and the fully qualified service name
      Parameters:
      type - The fully qualified service type
      name - The fully qualified service name
      Returns:
      the matching service reference or null if no match is found

    • lookupService

      public ServiceRef lookupService(String type, String name, int timeout) throws ServiceException
      Lookup the service given the fully qualified service type and the fully qualified service name and block until a match is found or the specified timeout has expired.
      Parameters:
      type - The fully qualified service type
      name - The fully qualified service name
      timeout - The timeout in milliseconds to block until a match is found
      Returns:
      the matching service reference or null if no match is found
      Throws:
      ServiceException

    • findServicesWithType

      public ServiceRef[] findServicesWithType(Class<?> protocol, long timeout) throws ServiceException
      Convenience method for making a request to find service providers of a specific service type and waiting a specified amount of time to find those services. It is more preferable, however, to use the "addServiceListener()" method instead so as to monitor the availability of services. Convenience method used when the type is derived from the protocol's name.
      Parameters:
      protocol - The protocol identifying the service type for which to find providers.
      timeout - Time to block in milliseconds while waiting for services to be discovered.
      Returns:
      An array of services which were found within the specified timeout
      Throws:
      ServiceException
      See Also:

    • findServicesWithType

      public ServiceRef[] findServicesWithType(String serviceType, long timeout) throws ServiceException
      Convenience method for making a request to find service providers of a specific service type and waiting a specified amount of time to find those services. It is more preferable, however, to use the "addServiceListener()" method instead so as to monitor the availability of services.
      Parameters:
      serviceType - The type of service to find.
      timeout - Time to block in milliseconds while waiting for services to be discovered.
      Returns:
      An array of services which were found within the specified timeout
      Throws:
      ServiceException
      See Also:

    • addServiceListener

      public void addServiceListener(Class<?> protocol, ServiceListener listener) throws ServiceException
      Add a listener for addition and removal of service providers. Convenience method used when the type is derived from the protocol's name.
      Parameters:
      protocol - The protocol identifying the service type.
      listener - The receiver of service availability events.
      Throws:
      ServiceException

    • addServiceListener

      public void addServiceListener(String type, ServiceListener listener) throws ServiceException
      Add a listener for addition and removal of service providers.
      Parameters:
      type - The type of service provided.
      listener - The receiver of service availability events.
      Throws:
      ServiceException

    • removeServiceListener

      public void removeServiceListener(ServiceListener listener)
      Remove a listener of service availability events.
      Parameters:
      listener - The listener of service availability events.

    • getDefaultType

      protected static String getDefaultType(Class<?> protocol)
      Form a valid type based on the specified protocol by replacing the protocol's name with a valid name in which "." is replaced by "_".
      Parameters:
      protocol - The protocol for which to get a valid type
      Returns:
      A valid type to represent the given protocol.

    • getHost

      public static String getHost(Object proxy)
      Get the remote host for the service
      Parameters:
      proxy - the proxy to the service at the remote host
      Returns:
      a string representation of the remote host

    • getPort

      public static int getPort(Object proxy)
      Get the remote port at which the service is available.
      Parameters:
      proxy - the proxy to the service at the remote host
      Returns:
      the remote port at which the service is available

    • getServiceName

      public static String getServiceName(Object proxy)
      Get the service name for the remote service
      Parameters:
      proxy - the proxy to the remote service
      Returns:
      The name of the remote service

    • getProtocol

      public static Class<?> getProtocol(Object proxy)
      Get the protocol of the remote proxy
      Parameters:
      proxy - the proxy to the remote service
      Returns:
      the interface implemented by the proxy

    • getClientHandler

      protected static xal.extension.service.ClientHandler<?> getClientHandler(Object proxy)
      Convenience method for getting the ClientHandler for the given proxy
      Parameters:
      proxy - the proxy for which we seek its client handler
      Returns:
      the client handler for the proxy