lightweightpeergroup.html

jxta的api库

<CODE>&nbsp;<A HREF="../../../net/jxta/service/Service.html" title="interface in net.jxta.service">Service</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../net/jxta/peergroup/LightWeightPeerGroup.html#lookupService(net.jxta.id.ID)">lookupService</A></B>(<A HREF="../../../net/jxta/id/ID.html" title="class in net.jxta.id">ID</A>&nbsp;name)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Lookup for a service by name.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="../../../net/jxta/peergroup/PeerGroup.html" title="interface in net.jxta.peergroup">PeerGroup</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../net/jxta/peergroup/LightWeightPeerGroup.html#newGroup(net.jxta.document.Advertisement)">newGroup</A></B>(<A HREF="../../../net/jxta/document/Advertisement.html" title="class in net.jxta.document">Advertisement</A>&nbsp;pgAdv)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Instantiate a peer group from its given advertisement. This instantiator
  requires that the ModuleImplAdvertisment for the peer group and the
  ModuleImplAdvertisements for the group's services be available for
  discovery within the current group.

  <p/>The pgAdv itself may be all new and unpublished. Therefore, the two
  typical uses of this routine are:

 <ul>
 <li>Creating an all new group with a new ID while using an existing
 and published implementation. (Possibly a new one published for
 that purpose). The information should first be gathered in a new
 PeerGroupAdvertisement which is then passed to this method.</li>

 <li>Instantiating a group which advertisement has already been
 discovered (therefore there is no need to find it by groupID
 again).</li>
 </ul>

 <p/>To create a group from a known implAdv, use
 <A HREF="../../../net/jxta/peergroup/PeerGroup.html#newGroup(net.jxta.peergroup.PeerGroupID, net.jxta.document.Advertisement, java.lang.String, java.lang.String)"><CODE>PeerGroup.newGroup(PeerGroupID,Advertisement,String,String)</CODE></A></TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="../../../net/jxta/peergroup/PeerGroup.html" title="interface in net.jxta.peergroup">PeerGroup</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../net/jxta/peergroup/LightWeightPeerGroup.html#newGroup(net.jxta.peergroup.PeerGroupID)">newGroup</A></B>(<A HREF="../../../net/jxta/peergroup/PeerGroupID.html" title="class in net.jxta.peergroup">PeerGroupID</A>&nbsp;gid)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Instantiate a group from its Peer Group ID only. Use this when using a
 group that has already been published and discovered.

 <p/>The typical uses of this routine are therefore:

 <ul>
   <li>Instantiating a peer group which is assumed to exist and whose Peer
   Group ID is already known.</li>

   <li>Creating a new peer group instance using an already published
   Group advertisement, typically published for that purpose. All other
   referenced advertisements must also be available.</li>
 </ul>

 <p/>To create a group from a known implAdv, just use
 <A HREF="../../../net/jxta/peergroup/PeerGroup.html#loadModule(net.jxta.id.ID, net.jxta.document.Advertisement)"><CODE>PeerGroup.loadModule(ID,Advertisement)</CODE></A> or even:<p>

 <p/><code>
 grp = new GroupSubClass();
 grp.init(parentGroup, gid, impladv);
 </code>

 <p/>then, <strong>REMEMBER TO PUBLISH THE GROUP IF IT IS ALL NEW.</strong></TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;<A HREF="../../../net/jxta/peergroup/PeerGroup.html" title="interface in net.jxta.peergroup">PeerGroup</A></CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../net/jxta/peergroup/LightWeightPeerGroup.html#newGroup(net.jxta.peergroup.PeerGroupID, net.jxta.document.Advertisement, java.lang.String, java.lang.String)">newGroup</A></B>(<A HREF="../../../net/jxta/peergroup/PeerGroupID.html" title="class in net.jxta.peergroup">PeerGroupID</A>&nbsp;gid,
         <A HREF="../../../net/jxta/document/Advertisement.html" title="class in net.jxta.document">Advertisement</A>&nbsp;impl,
         java.lang.String&nbsp;name,
         java.lang.String&nbsp;description)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Instantiates a new group from its elementary pieces
 and publishes the corresponding PeerGroupAdvertisement.
 The pieces are: the groups implementation adv, the group id,
 the name and description.

 <p/>The typical use of this routine is creating a whole new group based
 on a newly created and possibly unpublished implementation adv.

 <p/>This is a convenience method equivalent to either:

 <p/><pre>
 newGrp = thisGroup.loadModule(gid, impl);
 newGrp.publishGroup(name, description);
 </pre>
 <p/>or, but only if the implementation advertisement has been published:

 <p/><pre>
 newPGAdv = AdvertisementFactory.newAdvertisement(
                 PeerGroupAdvertisement.getAdvertisementType());
 newPGAdv.setPeerGroupID(gid);
 newPGAdv.setModuleSpecID(impl.getModuleSpecID());
 newPGAdv.setName(name);
 newPGAdv.setDescription(description);
 newGrp = thisGroup.newGroup(newPGAdv);
 </pre></TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../net/jxta/peergroup/LightWeightPeerGroup.html#publishGroup(java.lang.String, java.lang.String)">publishGroup</A></B>(java.lang.String&nbsp;name,
             java.lang.String&nbsp;description)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Publish this group's Peer Group Advertisment if it has not already been
 published. The Peer Group Advertisement is published into the Peer Group
 in which this group was instantiated, specifically the Peer Group whose
 <code>newGroup()</code> was called.

 <p/>Calling this method is only useful if the group is being created
 from scratch and the PeerGroup advertisement has not been
 created beforehand. In such a case, the group has never been named or
 described. Therefore this information has to be supplied here.

 <p/>If this group has already been previously published, this method does
 nothing.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;int</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../net/jxta/peergroup/LightWeightPeerGroup.html#startApp(java.lang.String[])">startApp</A></B>(java.lang.String[]&nbsp;args)</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Some Modules will wait for this method being invoked, before
 completing their initializatino to the point that they are fully
 functional. That is also the opportunity to supply arbitrary arguments
 (mostly to applications).
 
 <p/>If this module is a <A HREF="../../../net/jxta/peergroup/PeerGroup.html" title="interface in net.jxta.peergroup"><CODE>PeerGroup</CODE></A> service, it may be invoked
 several times depending on its return value.
 
 <p/>Note: the name of this method is historical and no-longer adequate.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../net/jxta/peergroup/LightWeightPeerGroup.html#stopApp()">stopApp</A></B>()</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;One can ask a Module to stop.
  The Module cannot be forced to comply, but in the future
  we might be able to deny it access to anything after some timeout.

  <p/>Note: the name of this method is no-longer adequate.</TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD ALIGN="right" VALIGN="top" WIDTH="1%"><FONT SIZE="-1">
<CODE>&nbsp;void</CODE></FONT></TD>
<TD><CODE><B><A HREF="../../../net/jxta/peergroup/LightWeightPeerGroup.html#unref()">unref</A></B>()</CODE>

<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Explicitly notifies a group interface that it will no-longer be
 used (similar to dispose). Does nothing to a real group object,
 only has an effect on a group interface.</TD>
</TR>
</TABLE>
&nbsp;<A NAME="methods_inherited_from_class_java.lang.Object"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#EEEEFF" CLASS="TableSubHeadingColor">
<TD><B>Methods inherited from class java.lang.Object</B></TD>
</TR>
<TR BGCOLOR="white" CLASS="TableRowColor">
<TD><CODE>clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait</CODE></TD>
</TR>
</TABLE>
&nbsp;
<P>

<!-- ============ FIELD DETAIL =========== -->


<!-- ========= CONSTRUCTOR DETAIL ======== -->

<A NAME="constructor_detail"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TD COLSPAN=1><FONT SIZE="+2">
<B>Constructor Detail</B></FONT></TD>
</TR>
</TABLE>

<A NAME="LightWeightPeerGroup(net.jxta.protocol.PeerGroupAdvertisement)"><!-- --></A><H3>
LightWeightPeerGroup</H3>
<PRE>
public <B>LightWeightPeerGroup</B>(<A HREF="../../../net/jxta/protocol/PeerGroupAdvertisement.html" title="class in net.jxta.protocol">PeerGroupAdvertisement</A>&nbsp;adv)</PRE>
<DL>
<DD>Constructor

 All classes that extend this class must invoke this
 constructor.
<P>
<DT><B>Parameters:</B><DD><CODE>adv</CODE> - PeerGroupAdvertisement of this LightWeightPeerGroup.
 Note that only the PeerGroupID is used.</DL>

<!-- ============ METHOD DETAIL ========== -->

<A NAME="method_detail"><!-- --></A>
<TABLE BORDER="1" WIDTH="100%" CELLPADDING="3" CELLSPACING="0" SUMMARY="">
<TR BGCOLOR="#CCCCFF" CLASS="TableHeadingColor">
<TD COLSPAN=1><FONT SIZE="+2">
<B>Method Detail</B></FONT></TD>
</TR>
</TABLE>

<A NAME="init(net.jxta.peergroup.PeerGroup, net.jxta.id.ID, net.jxta.document.Advertisement)"><!-- --></A><H3>
init</H3>
<PRE>
public void <B>init</B>(<A HREF="../../../net/jxta/peergroup/PeerGroup.html" title="interface in net.jxta.peergroup">PeerGroup</A>&nbsp;group,
                 <A HREF="../../../net/jxta/id/ID.html" title="class in net.jxta.id">ID</A>&nbsp;assignedID,
                 <A HREF="../../../net/jxta/document/Advertisement.html" title="class in net.jxta.document">Advertisement</A>&nbsp;implAdv)</PRE>
<DL>
<DD>Initialize the module, passing it its peer group and advertisement.
 
 <p/>Note: when subclassing one of the existing PeerGroup implementations
 (which implement Module), it may not be recommended to overload the init
 method. See the documentation of the PeerGroup class being subclassed.
<P>
<DD><DL>
<DT><B>Specified by:</B><DD><CODE><A HREF="../../../net/jxta/platform/Module.html#init(net.jxta.peergroup.PeerGroup, net.jxta.id.ID, net.jxta.document.Advertisement)">init</A></CODE> in interface <CODE><A HREF="../../../net/jxta/platform/Module.html" title="interface in net.jxta.platform">Module</A></CODE></DL>
</DD>
<DD><DL>
<DT><B>Parameters:</B><DD><CODE>group</CODE> - The PeerGroup from which this Module can obtain services.
  If this module is a service, this is also the PeerGroup of which this
  module is a service.<DD><CODE>assignedID</CODE> - Identity of Module within group.
  modules can use it as a the root of their namespace to create
  names that are unique within the group but predictible by the
  same module on another peer. This is normaly the ModuleClassID
  which is also the name under which the module is known by other
  modules. For a group it is the PeerGroupID itself.
  The parameters of a service, in the Peer configuration, are indexed
  by the assignedID of that service, and a Service must publish its
  run-time parameters in the Peer Advertisement under its assigned ID.<DD><CODE>implAdv</CODE> - The implementation advertisement for this
  Module. It is permissible to pass null if no implementation
  advertisement is available. This may happen if the
  implementation was selected by explicit class name rather than
  by following an implementation advertisement. Modules are not