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diff --git a/protocols/bundles/ch.ethz.iks.slp/src/site/xdoc/jSLP-OSGi/userguide.xml b/protocols/bundles/ch.ethz.iks.slp/src/site/xdoc/jSLP-OSGi/userguide.xml new file mode 100644 index 000000000..6795801fc --- /dev/null +++ b/protocols/bundles/ch.ethz.iks.slp/src/site/xdoc/jSLP-OSGi/userguide.xml @@ -0,0 +1,97 @@ +<?xml version="1.0" encoding="ISO-8859-1"?>
+<document>
+ <properties>
+ <title>jSLP-OSGi - Java SLP (Service Location Protocol) Implementation for OSGi. Getting started with jSLP-OSGi</title>
+ <author email="rellermeyer_AT_inf.ethz.ch">Jan S. Rellermeyer</author>
+ </properties>
+
+ <meta name="keyword" content="Java, SLP, jSLP, Service Location Protocol, OSGi, Userguide"/>
+ <meta name="description" content="jSLP is a pure Java implementation of RFC 2608 (SLP, Service Location Protocol, Version 2) with a RFC 2614 style API. It can be both SLP UserAgent (UA) and ServiceAgent (SA). jSLP-OSGi integrates SLP with OSGi (Open Service Gateway Initiative)."/>
+ <meta http-equiv="cache-control" content="no-cache"/>
+ <meta http-equiv="pragma" content="no-cache"/>
+ <meta http-equiv="robots" content="index, follow"/>
+
+<body>
+
+ <section name="Getting started with jSLP-OSGi">
+ <p>
+ jSLP OSGi registers <code>ch.ethz.iks.slp.ServiceLocationManager</code> as <code>ServiceFactory</code>.
+ The registered services are <code>ch.ethz.iks.slp.Advertiser</code> and <code>ch.ethz.iks.slp.Locator</code>
+ and every bundle requesting one of the services will get their own instance. Since requests for
+ <code>ServiceReferences</code> cannot pass parameters to the <code>ServiceFactory</code>,
+ the <code>Advertiser</code> and <code>Locator</code> instances will be created with the empty default
+ <code>Locale</code> and both classes have a setter method <code>.setLocale(Locale locale)</code> to change
+ the locale at runtime (this differs from the jSLP standalone version).
+ </p>
+ <p>
+ The following example shows how to get <code>Advertiser</code> and <code>Locator</code> instances and use them:
+<source>
+public class SLPTestBundle implements BundleActivator {
+
+ public void start(BundleContext context) throws Exception {
+
+ ServiceReference advRef = context.getServiceReference("ch.ethz.iks.slp.Advertiser");
+ ServiceReference locRef = context.getServiceReference("ch.ethz.iks.slp.Locator");
+
+ if (advRef != null) {
+ System.out.println("Got reference for Advertiser");
+ Advertiser advertiser = (Advertiser) context.getService(advRef);
+
+ advertiser.register(new ServiceURL("service:osgi:test://192.168.24.118", 20), null);
+ }
+
+ if (locRef != null) {
+ System.out.println("Got reference for Locator");
+ Locator locator = (Locator) context.getService(locRef);
+
+ ServiceLocationEnumeration slenum = locator.findServices(new ServiceType("service:osgi"), null, null);
+ System.out.println("RESULT:");
+ while (slenum.hasMoreElements()) {
+ System.out.println(slenum.nextElement());
+ }
+ }
+ }
+
+
+ public void stop(BundleContext context) throws Exception {
+
+ }
+
+}
+</source>
+ </p>
+ <p>
+ jSLP OSGi does not require <code>org.osgi.service.log</code> to run but if a bundle is present that provides this service,
+ jSLP OSGi makes use of it. If the service is not present, trace options passed by properties have no effect. jSLP-OSGi has
+ been successfully tested with <a href="http://flowsgi.inf.ethz.ch/concierge.html">Concierge OSGi</a>,
+ <a href="http://www.knopflerfish.org">Knopflerfish</a>, <a href="http://oscar.objectweb.org">Oscar</a> and
+ <a href="http://www.eclipse.org/equinox/">Eclipse Equinox</a>.
+ </p>
+ <p>
+ For developing Eclipse Plugins, it is recommended to checkout the jSLP-OSGi project from the
+ <a href="source-repository.html">subversion repository</a>. This project is already an Eclipse Plugin and
+ can be used as dependency for your own project. Unfortunately, Eclipse does not show the exception that is thrown
+ when jSLP runs on a linux box as non-root user and it tries to open port 427. Instead, it will print a plain
+ <code>ExceptionInInitializer</code>. The result is a general unavailability of the requested Locator or Advertiser instance.
+ </p>
+ <p>
+ Furthermore, Eclipse uses a resolving and starting strategy which is different from traditional OSGi. jSLP has
+ <code>Eclipse-LazyStart</code> set so it is started whenever a class from the bundle is accessed. This somewhat collides
+ with the OSGi service model where bundles are completely decoupled. So in the above example, jSLP as a Plugin is never
+ started and no Advertiser or Locator instance can be retrieved. To prevent this, simple use
+<source>
+ ServiceReference advRef = context.getServiceReference(Advertiser.class.getName());
+</source>
+ The call to the static field <code>class</code> will force the resolving of <code>ch.ethz.slp.Advertiser</code>,
+ the Plugin will be started and thus the ServiceFactory registered with the OSGi registry. (The same indeed works
+ for the Locator)
+ </p>
+ <p>
+ For debugging, jSLP-OSGi features the <code>ch.ethz.iks.slp.debug</code> property. If set to <code>true</code>
+ and a LogService is present, jSLP-OSGi prints additional information about internal state changes which makes it
+ easier to debug applications.
+ </p>
+ </section>
+
+</body>
+</document>
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