*** This class provides Binary Compatibility only, not Source Compatibility ***

Package com.sas.services.discovery

Class HostAttribute

java.lang.Object
com.sas.services.AbstractServiceAttribute
com.sas.services.discovery.HostAttribute
All Implemented Interfaces:
ServiceAttributeInterface, Serializable
@SASScope("ALL") @BinaryCompatibilityOnly public final class HostAttribute extends AbstractServiceAttribute
A foundation service discovery attribute which may be used to locate a service which has been deployed on a particular host by using the host's name and/or IP address.

When a service is deployed, a HostAttribute will be added to its service discovery configuration for each InetAddress associated with its host. This will enable one to find a service that is deployed on a particular host.

Examples

Examples are provided to find a foundation service deployed on:

Example 1: Find a service that was deployed on this host

This example shows how to define a service template that can be used to discover an Authentication Service that was deployed on this host.

To find a service that was deployed on this host, define a service template that specifies one or more interfaces that the desired service must satisfy and a HostAttribute initialized to the desired host by specifying either the host's name and/or its IP address. 

 
 import java.net.InetAddress;
  
 import com.sas.services.discovery.DiscoveryService;
 import com.sas.services.discovery.HostAttribute;
 import com.sas.services.discovery.ServiceTemplate;
 import com.sas.services.security.AuthenticationServiceInterface;
  
 ...
  
 // define a service template that can be used to 
 // lookup an Authentication Service
 Class[] desiredServiceInterface = new Class[] {
    AuthenticationServiceInterface.class};
  
 // get this host's InetAddress
 // note: a host may have multiple addresses
 InetAddress inetAddress = getInetAddress();
  
 ServiceAttributeInterface serviceAttributes = new ServiceAttributeInterface[] {
    new HostAttribute(inetAddress)};
   
 // create a service lookup template specifying the required
 // service interface(s) and a service attribute for a
 // service that was deployed on this host
 ServiceTemplate serviceTemplate = new ServiceTemplate(
    desiredServiceInterface,
    serviceAttributes);
  
 // discover a service satisfying the service template
 AuthenticationServiceInterface authenticationService = (AuthenticationServiceInterface)
    DiscoveryService.defaultInstance().findService(serviceTemplate);
    
 ...
 
 // Utility method used to determine the host's InetAddress:
 
 import java.net.InetAddress;
 import java.net.NetworkInterface;
 import java.util.Enumeration;
  
 import com.sas.services.deployment.RMIConfiguration;
  
 ...
  
 // get this host's InetAddress discarding the "localhost" address
 InetAddress getInetAddress () {
  
    InetAddress theInetAddress = null;
     
    try {
       final Enumeration netInterfaces = NetworkInterface.getNetworkInterfaces();
       NetworkInterface networkInterface = null;
       InetAddress inetAddress = null;
       Enumeration inetAddresses = null;
       while (netInterfaces.hasMoreElements()) {
            networkInterface= (NetworkInterface) netInterfaces.nextElement();
            inetAddresses = networkInterface.getInetAddresses();
            while (inetAddresses.hasMoreElements()) {
               inetAddress = (InetAddress) inetAddresses.nextElement();
              if (!RMIConfiguration.LOCALHOST.equals(inetAddress.getHostName())) { 
                 theInetAddress = inetAddress;
                 break;
              }
           } 
        }
     }
     catch (ClassCastException e) {
        // handle exception
     }
     
     return theInetAddress;
 
 }

Example 2: Find a service that was deployed on a host using its name

This example shows how to define a service template that can be used to discover a foundation Authentication service that was deployed on a host named "xxx.acme.com".

To find a service that was deployed on this host, define a service template that specifies one or more interfaces that the desired service must satisfy and a HostAttribute initialized using the host's name. 

 
 import com.sas.services.discovery.DiscoveryService;
 import com.sas.services.discovery.HostAttribute;
 import com.sas.services.discovery.ServiceTemplate;
 import com.sas.services.security.AuthenticationServiceInterface;
  
 ...
  
 // define a service template that can be used to 
 // lookup an Authentication Service
 Class[] desiredServiceInterface = new Class[] {
    AuthenticationServiceInterface.class};
  
 // the name of the desired host on which a service was deployed
 String hostName = "xxx.acme.com";
  
 // find a service on for a given host name
 ServiceAttributeInterface serviceAttributes = new ServiceAttributeInterface[] {
    new HostAttribute(
       hostName,
       null)};//don't care about the host's address
   
 // create a service lookup template specifying the required
 // service interface(s) and a service attribute for a
 // service that was deployed on the specified host
 ServiceTemplate serviceTemplate = new ServiceTemplate(
    desiredServiceInterface,
    serviceAttributes);
  
 // discover a service satisfying the service template
 AuthenticationServiceInterface authenticationService = (AuthenticationServiceInterface)
    DiscoveryService.defaultInstance().findService(serviceTemplate);

Example 3: Find a service that was deployed on a host using its address

This example shows how to define a service template that can be used to discover a foundation Authentication service that was deployed on a host whose IP address is "99.99.99.99".

To find a service that was deployed on this host, define a service template that specifies one or more interfaces that the desired service must satisfy and a HostAttribute initialized using the host's address. 

 
 import com.sas.services.discovery.DiscoveryService;
 import com.sas.services.discovery.HostAttribute;
 import com.sas.services.discovery.ServiceTemplate;
 import com.sas.services.security.AuthenticationServiceInterface;
  
 ...
  
 // define a service template that can be used to 
 // lookup an Authentication Service
 Class[] desiredServiceInterface = new Class[] {
    AuthenticationServiceInterface.class};
  
 // the IP address of the desired host on which a service was deployed
 String hostAddress = "99.99.99.99";
  
 // find a service on for a given host name
 ServiceAttributeInterface serviceAttributes = new ServiceAttributeInterface[] {
    new HostAttribute(
       null,//don't care about the host's name
       hostAddress)};
   
 // create a service lookup template specifying the required
 // service interface(s) and a service attribute for a
 // service that was deployed on the specified host
 ServiceTemplate serviceTemplate = new ServiceTemplate(
    desiredServiceInterface,
    serviceAttributes);
  
 // discover a service satisfying the service template
 AuthenticationServiceInterface authenticationService = (AuthenticationServiceInterface)
    DiscoveryService.defaultInstance().findService(serviceTemplate);

Since:
9.2
See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    String
    address
    The host's IP address.
    String
    host
    The host's name.

  • Constructor Summary

    Constructors
    Constructor
    Description
    HostAttribute()
    Constructs a service discovery attribute representing a host with its name and address to null.
    HostAttribute(String hostName)
    Constructs an attribute which may be used to locate a remotely accessible foundation service which was deployed on a particular host.
    HostAttribute(String hostName, String hostAddress)
    Constructs a service discovery attribute representing a host using the specified name and address.
    HostAttribute(InetAddress inetAddress)
    Constructs a service discovery attribute representing a host by initializing the host's name and address using values obtained from InetAddress.getHostName() and InetAddress.getHostAddress().

  • Method Summary

    Modifier and Type
    Method
    Description
    Map<String,String>
    getFieldNameToValueMap()
    Gets a map of this attribute's fields and their values.

    Methods inherited from class com.sas.services.AbstractServiceAttribute

    equals, hashCode, toString

    Methods inherited from class java.lang.Object

    clone, finalize, getClass, notify, notifyAll, wait, wait, wait

  • Field Details

    • host

      public String host
      The host's name.

    • address

      public String address
      The host's IP address.

  • Constructor Details

    • HostAttribute

      public HostAttribute()
      Constructs a service discovery attribute representing a host with its name and address to null.

    • HostAttribute

      public HostAttribute(InetAddress inetAddress)
      Constructs a service discovery attribute representing a host by initializing the host's name and address using values obtained from InetAddress.getHostName() and InetAddress.getHostAddress().

      Since this attribute initializes both the name and address, a client can locate a foundation service deployed on a particular host by matching the host's name and/or address.

      One may also use HostAttribute(String, String) to construct an instance using string values for the host's name and address.

      Parameters:
      inetAddress - An address representing the host on which a foundation service has been deployed.
      Throws:
      IllegalArgumentException - if a null parameter is specified.

    • HostAttribute

      public HostAttribute(String hostName)
      Constructs an attribute which may be used to locate a remotely accessible foundation service which was deployed on a particular host.
      Parameters:
      hostName - Internet host name.

    • HostAttribute

      public HostAttribute(String hostName, String hostAddress)
      Constructs a service discovery attribute representing a host using the specified name and address.

      A convenience constructor HostAttribute(InetAddress) is also provided if one would prefer to initialize this attribute using a host name and address obtained from an InetAddress.

      Parameters:
      hostName - Internet host name.
      hostAddress - Internet host address.

  • Method Details

    • getFieldNameToValueMap

      public Map<String,String> getFieldNameToValueMap()
      Gets a map of this attribute's fields and their values.
      • host
      • address
      Overrides:
      getFieldNameToValueMap in class AbstractServiceAttribute
      Returns:
      Map keyed by the String names of a field to their values.