discoveryserviceinterface.html

jxta的api库

  in two ways 1. by specifying a null peerid, the discovery message is
  propagated on the local sub-net utilizing ip multicast. In addition to the
  multicast it is also propagated to rendezvous points. 2. by passing a
  peerid, the EndpointRouter will attempt to resolve destination peer's
  endpoints or route the message to other routers in attempt to reach the
  peer.
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html#getRemoteAdvertisements(java.lang.String, int, java.lang.String, java.lang.String, int)">getRemoteAdvertisements</A></CODE> in interface <CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html" title="interface in net.jxta.discovery">DiscoveryService</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>peer</CODE> - id of a peer, specifying null results in a propagate
      within the group<DD><CODE>type</CODE> - Discovery type PEER, GROUP, ADV<DD><CODE>attribute</CODE> - attribute name to narrow disocvery to Valid values for
      this parameter are null (don't care), or exact element name in the
      advertisement of interest (e.g. "Name")<DD><CODE>value</CODE> - value of attribute to narrow disocvery to valid values for
      this parameter are null (don't care), Exact value, or use of wild
      card(s) (e.g. if a Advertisement defines <Name>FooBar</name> , a value
      of "*bar", "foo*", or "*ooB*", will return the Advertisement<DD><CODE>threshold</CODE> - the upper limit of responses from one peer
        threshold of 0, and type od PEER has a special behaviour
        peers respond with own adv only.
<DT><B>Returns:</B><DD>query ID for this discovery query</DL>
</DD>
</DL>
<HR>

<A NAME="getRemoteAdvertisements(java.lang.String, int, java.lang.String, java.lang.String, int, net.jxta.discovery.DiscoveryListener)"><!-- --></A><H3>
getRemoteAdvertisements</H3>
<PRE>
public int <B>getRemoteAdvertisements</B>(java.lang.String&nbsp;peer,
                                   int&nbsp;type,
                                   java.lang.String&nbsp;attribute,
                                   java.lang.String&nbsp;value,
                                   int&nbsp;threshold,
                                   <A HREF="../../../../net/jxta/discovery/DiscoveryListener.html" title="interface in net.jxta.discovery">DiscoveryListener</A>&nbsp;listener)</PRE>
<DL>
<DD>This method discovers PeerAdvertisements, GroupAdvertisements and jxta
  Advertisements. jxta Advertisements are documents that describe pipes,
  services, etc. The discovery scope can be narrowed down firstly by Name and
  Value pair where the match is an exact match, secondly by setting a upper
  limit where the responding peer will not exceed. DiscoveryServiceImpl can
  be performed in two ways 1. by specifying a null peerid, the discovery
  message is propagated on the local sub-net utilizing ip multicast. In
  addition to the multicast it is also propagated to rendezvous points. 2. by
  passing a peerid, the EndpointRouter will attempt to resolve destination
  peer's endpoints or route the message to other routers in attempt to reach
  the peer.
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html#getRemoteAdvertisements(java.lang.String, int, java.lang.String, java.lang.String, int, net.jxta.discovery.DiscoveryListener)">getRemoteAdvertisements</A></CODE> in interface <CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html" title="interface in net.jxta.discovery">DiscoveryService</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>attribute</CODE> - attribute name to narrow disocvery to Valid values for
      this parameter are null (don't care), or exact element name in the
      advertisement of interest (e.g. "Name")<DD><CODE>value</CODE> - value of attribute to narrow disocvery to valid values for
      this parameter are null (don't care), Exact value, or use of wild
      card(s) (e.g. if a Advertisement defines <Name>FooBar</name> , a value
      of "*bar", "foo*", or "*ooB*", will return the Advertisement<DD><CODE>threshold</CODE> - the upper limit of responses from one peer
        threshold of 0, and type od PEER has a special behaviour<DD><CODE>peer</CODE> - id of a peer, specifying null results in a propagate
      within the group<DD><CODE>type</CODE> - Discovery type PEER, GROUP, ADV<DD><CODE>listener</CODE> - the listener which will be called back with found
      advertisements.
<DT><B>Returns:</B><DD>query ID for this discovery query</DL>
</DD>
</DL>
<HR>

<A NAME="getLocalAdvertisements(int, java.lang.String, java.lang.String)"><!-- --></A><H3>
getLocalAdvertisements</H3>
<PRE>
public java.util.Enumeration <B>getLocalAdvertisements</B>(int&nbsp;type,
                                                    java.lang.String&nbsp;attribute,
                                                    java.lang.String&nbsp;value)
                                             throws java.io.IOException</PRE>
<DL>
<DD>Retrieve Stored Peer, Group, and General Advertisements
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html#getLocalAdvertisements(int, java.lang.String, java.lang.String)">getLocalAdvertisements</A></CODE> in interface <CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html" title="interface in net.jxta.discovery">DiscoveryService</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>type</CODE> - Discovery type PEER, GROUP, ADV<DD><CODE>attribute</CODE> - attribute name to narrow disocvery to Valid values
      for this parameter are null (don't care), or exact element name in the
      advertisement of interest (e.g. "Name")<DD><CODE>value</CODE> - value of attribute to narrow disocvery to valid
      values for this parameter are null (don't care), Exact value, or use of
      wild card(s) (e.g. if a Advertisement defines <Name>FooBar</name> , a
      value of "*bar", "foo*", or "*ooB*", will return the Advertisement
<DT><B>Returns:</B><DD>Enumeration of stored advertisements/structured
      documents
<DT><B>Throws:</B>
<DD><CODE>java.io.IOException</CODE> - - If an I/O error occurs</DL>
</DD>
</DL>
<HR>

<A NAME="flushAdvertisement(net.jxta.document.Advertisement)"><!-- --></A><H3>
flushAdvertisement</H3>
<PRE>
public void <B>flushAdvertisement</B>(<A HREF="../../../../net/jxta/document/Advertisement.html" title="class in net.jxta.document">Advertisement</A>&nbsp;adv)
                        throws java.io.IOException</PRE>
<DL>
<DD>flush a stored Advertisement
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html#flushAdvertisement(net.jxta.document.Advertisement)">flushAdvertisement</A></CODE> in interface <CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html" title="interface in net.jxta.discovery">DiscoveryService</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>adv</CODE> - Advertisement to remove
<DT><B>Throws:</B>
<DD><CODE>java.io.IOException</CODE> - - If an I/O error occurs</DL>
</DD>
</DL>
<HR>

<A NAME="flushAdvertisements(java.lang.String, int)"><!-- --></A><H3>
flushAdvertisements</H3>
<PRE>
public void <B>flushAdvertisements</B>(java.lang.String&nbsp;id,
                                int&nbsp;type)
                         throws java.io.IOException</PRE>
<DL>
<DD>flushs stored Advertisement(s),
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html#flushAdvertisements(java.lang.String, int)">flushAdvertisements</A></CODE> in interface <CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html" title="interface in net.jxta.discovery">DiscoveryService</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>id</CODE> - Document ID, Peer ID, or PeerGroup ID
                         flushs all content of type "type"<DD><CODE>type</CODE> - Discovery type PEER, GROUP, ADV
<DT><B>Throws:</B>
<DD><CODE>java.io.IOException</CODE> - - If an I/O error occurs</DL>
</DD>
</DL>
<HR>

<A NAME="getAdvExpirationTime(net.jxta.id.ID, int)"><!-- --></A><H3>
getAdvExpirationTime</H3>
<PRE>
public long <B>getAdvExpirationTime</B>(<A HREF="../../../../net/jxta/id/ID.html" title="class in net.jxta.id">ID</A>&nbsp;id,
                                 int&nbsp;type)</PRE>
<DL>
<DD>Returns the maximum duration in milliseconds for which this document
  should be cached by those other than the publisher. This value is either
  the cache lifetime or the remaining lifetime of the document, whichever
  is less.
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html#getAdvExpirationTime(net.jxta.id.ID, int)">getAdvExpirationTime</A></CODE> in interface <CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html" title="interface in net.jxta.discovery">DiscoveryService</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>id</CODE> - Document ID, Peer ID, or PeerGroup ID<DD><CODE>type</CODE> - Discovery type PEER, GROUP, ADV
<DT><B>Returns:</B><DD>the relative time in milliseconds at which remote peers should
 refresh this document. -1 is returned if the file is not known or
  already expired</DL>
</DD>
</DL>
<HR>

<A NAME="getAdvLifeTime(net.jxta.id.ID, int)"><!-- --></A><H3>
getAdvLifeTime</H3>
<PRE>
public long <B>getAdvLifeTime</B>(<A HREF="../../../../net/jxta/id/ID.html" title="class in net.jxta.id">ID</A>&nbsp;id,
                           int&nbsp;type)</PRE>
<DL>
<DD>Returns the maximum duration in milliseconds for which this document
  should be kept in local cache
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html#getAdvLifeTime(net.jxta.id.ID, int)">getAdvLifeTime</A></CODE> in interface <CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html" title="interface in net.jxta.discovery">DiscoveryService</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>id</CODE> - Document ID, Peer ID, or PeerGroup ID<DD><CODE>type</CODE> - Discovery type PEER, GROUP, ADV
<DT><B>Returns:</B><DD>the relative time in milliseconds at which remote peers should
 refresh this document. -1 is returned if the file is not known or
 already expired</DL>
</DD>
</DL>
<HR>

<A NAME="getAdvExpirationTime(net.jxta.document.Advertisement)"><!-- --></A><H3>
getAdvExpirationTime</H3>
<PRE>
public long <B>getAdvExpirationTime</B>(<A HREF="../../../../net/jxta/document/Advertisement.html" title="class in net.jxta.document">Advertisement</A>&nbsp;adv)</PRE>
<DL>
<DD>Returns the maximum duration in milliseconds for which this document
  should be cached by those other than the publisher. This value is either
  the cache lifetime or the remaining lifetime of the document, whichever
  is less.
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html#getAdvExpirationTime(net.jxta.document.Advertisement)">getAdvExpirationTime</A></CODE> in interface <CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html" title="interface in net.jxta.discovery">DiscoveryService</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>adv</CODE> - Advertisement
<DT><B>Returns:</B><DD>the relative time in milliseconds at which remote peers should
 refresh this document. -1 is returned if the file is not known or
  already expired</DL>
</DD>
</DL>
<HR>

<A NAME="getAdvLifeTime(net.jxta.document.Advertisement)"><!-- --></A><H3>
getAdvLifeTime</H3>
<PRE>
public long <B>getAdvLifeTime</B>(<A HREF="../../../../net/jxta/document/Advertisement.html" title="class in net.jxta.document">Advertisement</A>&nbsp;adv)</PRE>
<DL>
<DD>Returns the maximum duration in milliseconds for which this document
  should be kept in local cache
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html#getAdvLifeTime(net.jxta.document.Advertisement)">getAdvLifeTime</A></CODE> in interface <CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html" title="interface in net.jxta.discovery">DiscoveryService</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>adv</CODE> - Advertisement
<DT><B>Returns:</B><DD>the relative time in milliseconds at which remote peers should
 refresh this document. -1 is returned if the file is not known or
 already expired</DL>
</DD>
</DL>
<HR>

<A NAME="publish(net.jxta.document.Advertisement, int)"><!-- --></A><H3>
publish</H3>
<PRE>
public void <B>publish</B>(<A HREF="../../../../net/jxta/document/Advertisement.html" title="class in net.jxta.document">Advertisement</A>&nbsp;adv,
                    int&nbsp;type)
             throws java.io.IOException</PRE>
<DL>
<DD>Publish an advertisement with a default lifetime of <code>
  DEFAULT_LIFETIME</code> and default expiration time for "others" of <code>DEFAULT_EXPIRATION</code>
  Advertisement indexes are shared with a rendezvous peer upon connect,
  and subsequent publications are shared at a an implementation specified interval
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html#publish(net.jxta.document.Advertisement, int)">publish</A></CODE> in interface <CODE><A HREF="../../../../net/jxta/discovery/DiscoveryService.html" title="interface in net.jxta.discovery">DiscoveryService</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>adv</CODE> - publish an adverisement within this group<DD><CODE>type</CODE> - Discovery type PEER, GROUP, ADV