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From conflue...@apache.org
Subject [CONF] Apache Felix > Apache Felix Framework Usage Documentation
Date Fri, 24 Dec 2010 16:18:00 GMT
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    <h2><a href="https://cwiki.apache.org/confluence/display/FELIX/Apache+Felix+Framework+Usage+Documentation">Apache
Felix Framework Usage Documentation</a></h2>
    <h4>Page <b>edited</b> by             <a href="https://cwiki.apache.org/confluence/display/~heavy@ungoverned.org">Richard
S. Hall</a>
    </h4>
        <br/>
                         <h4>Changes (3)</h4>
                                 
    
<div id="page-diffs">
            <table class="diff" cellpadding="0" cellspacing="0">
            <tr><td class="diff-snipped" >...<br></td></tr>
            <tr><td class="diff-unchanged" >* [Bundle Auto-Deploy|#auto-deploy]
<br>* [Configuring the Framework|#configuring-framework] <br></td></tr>
            <tr><td class="diff-deleted-lines" style="color:#999;background-color:#fdd;text-decoration:line-through;">**
[Migrating from Earlier Versions|#migrating] <br></td></tr>
            <tr><td class="diff-unchanged" >** [System Property Substitution|#property-substitution]
<br>* [Configuring Bundles|#configuring-bundles] <br></td></tr>
            <tr><td class="diff-snipped" >...<br></td></tr>
            <tr><td class="diff-unchanged" >{noformat} <br> <br></td></tr>
            <tr><td class="diff-changed-lines" >Configuration and system properties
are accessible at run time via {{BundleContext.getProperty()}}, but configuration properties
override system properties. <span class="diff-added-words"style="background-color: #dfd;">For
more information about available configuration properties, refer to the [Apache Felix Framework
Configuration Properties] document. The Felix framework distribution contains a default {{conf/config.properties}}.</span>
<br></td></tr>
            <tr><td class="diff-unchanged" > <br></td></tr>
            <tr><td class="diff-deleted-lines" style="color:#999;background-color:#fdd;text-decoration:line-through;">The
following configuration properties are for the launcher: <br> <br>* {{felix.auto.deploy.dir}}
\- Specifies the auto-deploy directory from which bundles are automatically deploy at framework
startup. The default is the {{bundle/}} directory of the current directory. <br>* {{felix.auto.deploy.action}}
\- Specifies a comma-delimited list of actions to be performed on bundle JAR files found in
the auto-deploy directory. The possible actions are {{install}}, {{update}}, {{start}}, and
{{uninstall}}. An undefined or blank value is equivalent to disabling auto-deploy processing.
<br>* {{felix.auto.install.&lt;n&gt;}} \- Space-delimited list of bundle URLs
to automatically install when Felix is started, where {{&lt;n&gt;}} is the start level
into which the bundle will be installed (e.g., {{felix.auto.install.2}}). <br>* {{felix.auto.start.&lt;n&gt;}}
\- Space-delimited list of bundle URLs to automatically install and start when Felix is started,
where {{&lt;n&gt;}} is the start level into which the bundle will be installed (e.g.,
{{felix.auto.start.2}}). <br>* {{felix.shutdown.hook}} \- Specifies whether the launcher
should install a shutdown hook to cleanly shutdown the framework on process exit. The default
value is {{true}}. <br> <br>The following configuration properties are for the
framework (properties starting with &quot;{{felix}}&quot; are specific to Felix, while
those starting with &quot;{{org.osgi}}&quot; are standard OSGi properties): <br>
<br>* {{org.osgi.framework.storage}} \- Sets the directory to use as the bundle cache;
by default bundle cache directory is {{felix-cache}} in the current working directory. The
value should be a valid directory name. The directory name can be either absolute or relative.
Relative directory names are relative to the current working directory. The specified directory
will be created if it does not exist. <br>* {{felix.cache.rootdir}} \- Sets the root
directory used to calculate the bundle cache directory for relative directory names. If {{org.osgi.framework.storage}}
is set to a relative name, by default it is relative to the current working directory. If
this property is set, then it will be calculated as being relative to the specified root directory.
<br>* {{org.osgi.framework.storage.clean}} \- Determines whether the bundle cache is
flushed. The value can either be &quot;{{none}}&quot; or &quot;{{onFirstInit}}&quot;,
where &quot;{{none}}&quot; does not flush the bundle cache and &quot;{{onFirstInit}}&quot;
flushes the bundle cache when the framework instance is first initialized. The default value
is &quot;{{none}}&quot;. <br>* {{felix.cache.bufsize}} \- Sets the buffer size
to be used by the cache; the default value is 4096. The integer value of this string provides
control over the size of the internal buffer of the disk cache for performance reasons. <br>*
{{org.osgi.framework.system.packages}} \- Specifies a comma-delimited list of packages that
should be exported via the System Bundle from the framework class loader. The framework will
set this to a reasonable default. If the value is specified, it replaces any default value.
<br>* {{org.osgi.framework.system.packages.extra}} \- Specifies a comma-delimited list
of packages that should be exported via the System Bundle from the framework class loader
in addition to the packages in {{org.osgi.framework.system.packages}}. The default value is
empty. If a value is specified, it is appended to the list of default or specified packages
in {{org.osgi.framework.system.packages}}. <br>* {{org.osgi.framework.bootdelegation}}
\- Specifies a comma-delimited list of packages that should be made implicitly available to
all bundles from the parent class loader. It is recommended not to use this property since
it breaks modularity. The default value is empty. <br>* {{org.osgi.framework.bundle.parent}}
\- Specifies which class loader is used for boot delegation. Possible values are: {{boot}}
for the boot class loader, {{app}} for the application class loader, {{ext}} for the extension
class loader, and {{framework}} for the framework&#39;s class loader. The default is {{boot}}.
<br>* {{felix.bootdelegation.implicit}} \- Specifies whether the framework should try
to guess when to implicitly boot delegate to ease integration with external code. The default
value is {{true}}. <br>* {{felix.systembundle.activators}} \- A {{List}} of {{BundleActivator}}
instances that are started/stopped when the System Bundle is started/stopped. The specified
instances will receive the System Bundle&#39;s {{BundleContext}} when invoked. (This property
cannot be set in the configuration file since it requires instances; it can only be passed
into Felix&#39; constructor directly.) <br>* {{felix.log.logger}} \- An instance
of {{Logger}} that the framework uses as its default logger. (This property cannot be set
in the configuration file since it requires an instance; it can only be passed into Felix&#39;
constructor directly.) <br>* {{felix.log.level}} \- An integer value indicating the
degree of logging reported by the framework; the higher the value the more logging is reported.
If zero (&#39;0&#39;) is specified, then logging is turned off completely. The log
levels match those specified in the OSGi Log Service (i.e., 1 = error, 2 = warning, 3 = information,
and 4 = debug). The default value is 1. <br>* {{org.osgi.framework.startlevel.beginning}}
\- The initial start level of the framework once it starts execution; the default value is
1. <br>* {{felix.startlevel.bundle}} \- The default start level for newly installed
bundles; the default value is 1. <br>* {{felix.service.urlhandlers}} \- Flag to indicate
whether to activate the URL Handlers service for the framework instance; the default value
is &quot;{{true}}&quot;. Activating the URL Handlers service will result in the {{URL.setURLStreamHandlerFactory()}}
and {{URLConnection.setContentHandlerFactory()}} being called. <br> <br>The Felix
framework distribution contains a default {{conf/config.properties}}. <br> <br>{anchor:migrating}
<br> <br>h3. Migrating from Earlier Versions <br> <br>Apache Felix
Framework {{2.0.0}} introduced some configuration property changes. This section describes
the differences from older versions of the framework. <br> <br>* *Removed* <br>**
{{felix.embedded.execution}} \- No longer needed, since the framework now never calls {{System.exit()}};
the creator of the framework is now always responsible for exiting the VM. <br>** {{felix.strict.osgi}}
\- No longer needed, since all non-specification features have been removed. <br>**
{{felix.cache.dir}} \- No longer needed, since Felix no longer uses bundle cache profiles
for saving sets of bundles. <br>** {{felix.cache.profile}} \- No longer needed, since
the framework no longer uses bundle cache profiles for saving sets of bundles. <br>**
{{felix.fragment.validation}} \- No longer needed, since the framework supports fragments.
<br>* *Renamed* <br>** {{felix.cache.profiledir}} \- The equivalent of this property
is now named {{org.osgi.framework.storage}}. <br>** {{felix.startlevel.framework}} \-
The equivalent of this property is now named {{org.osgi.framework.startlevel.beginning}}.
<br>* *Introduced* <br>** {{org.osgi.framework.system.packages.extra}} \- New
property, as described above, added to align with standard framework API. <br>** {{org.osgi.framework.storage.clean}}
\- New property, as described above, added to align with standard framework API. <br>**
{{felix.cache.rootdir}} \- Introduced as a result of removing bundle profiles to help resolve
relative bundle cache directories. <br> <br>For the most part, these changes are
minor and previous behavior achieved from older configuration properties is either easily
attained with the new properties or no longer necessary. <br> <br></td></tr>
            <tr><td class="diff-unchanged" >{anchor:property-substitution} <br>
<br></td></tr>
            <tr><td class="diff-snipped" >...<br></td></tr>
        </table>
</div>                            <h4>Full Content</h4>
                    <div class="notificationGreySide">
        <h1><a name="ApacheFelixFrameworkUsageDocumentation-ApacheFelixFrameworkUsageDocumentation"></a>Apache
Felix Framework Usage Documentation</h1>

<ul>
	<li><a href="#ApacheFelixFrameworkUsageDocumentation-downloadingframework">Downloading
the Framework</a></li>
	<li><a href="#ApacheFelixFrameworkUsageDocumentation-startingframework">Starting
the Framework</a></li>
	<li><a href="#ApacheFelixFrameworkUsageDocumentation-frameworkshell">Framework
Shell</a>
	<ul>
		<li><a href="#ApacheFelixFrameworkUsageDocumentation-installingbundles">Installing
Bundles</a></li>
		<li><a href="#ApacheFelixFrameworkUsageDocumentation-installingbundlesproxies">Web
Proxy Issues when Installing Bundles</a></li>
	</ul>
	</li>
	<li><a href="#ApacheFelixFrameworkUsageDocumentation-autodeploy">Bundle Auto-Deploy</a></li>
	<li><a href="#ApacheFelixFrameworkUsageDocumentation-configuringframework">Configuring
the Framework</a>
	<ul>
		<li><a href="#ApacheFelixFrameworkUsageDocumentation-propertysubstitution">System
Property Substitution</a></li>
	</ul>
	</li>
	<li><a href="#ApacheFelixFrameworkUsageDocumentation-configuringbundles">Configuring
Bundles</a></li>
	<li><a href="#ApacheFelixFrameworkUsageDocumentation-feedback">Feedback</a></li>
</ul>


<p><a name="ApacheFelixFrameworkUsageDocumentation-downloadingframework"></a></p>

<h2><a name="ApacheFelixFrameworkUsageDocumentation-DownloadingtheFramework"></a>Downloading
the Framework</h2>

<p>Go to the <a href="/confluence/display/FELIX/downloads" title="downloads">downloads</a>
page and download the latest Felix framework distribution.</p>

<p><a name="ApacheFelixFrameworkUsageDocumentation-startingframework"></a></p>

<h2><a name="ApacheFelixFrameworkUsageDocumentation-StartingtheFramework"></a>Starting
the Framework</h2>

<p>Start the framework from the installation directory by typing:</p>

<div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent
panelContent">
<pre>java -jar bin/felix.jar
</pre>
</div></div>

<p>The framework launcher starts the framework and installs and starts all bundles contained
in the <tt>bundle</tt> directory of the current directory. By default, the bundle
directory contains shell-related bundles providing a textual user interface to interact with
the framework. Bundles installed into the framework are copied into a bundle cache directory
for subsequent executions. By default, the framework creates a cache directory, called <tt>felix-cache</tt>,
in your current working directory. If you want to start the framework using a different bundle
cache directory, you can do so like this:</p>

<div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent
panelContent">
<pre>java -jar bin/felix.jar &lt;cache-path&gt;
</pre>
</div></div>

<p>Where <tt>&lt;cache-path&gt;</tt> is the path you want to use
as the bundle cache. If you specify a relative cache path, then it will be treated as relative
to the current working directory.</p>

<div class='panelMacro'><table class='infoMacro'><colgroup><col width='24'><col></colgroup><tr><td
valign='top'><img src="/confluence/images/icons/emoticons/information.gif" width="16"
height="16" align="absmiddle" alt="" border="0"></td><td><b>Useful Information</b><br
/>Previous versions of the framework prompted for a profile name when executed. The profile
name was used to create a directory inside <tt>.felix/</tt> in the user home directory.
This approach allowed users to have different sets of bundles for different purposes, e.g.,
testing, production, etc. If this behavior is still desired, it is very easy to mimic. Modify
<tt>conf/config.properties</tt> to include "<tt>felix.cache.rootdir=${user.home}/.felix</tt>".
Now, if you start Felix with something like "<tt>java -jar bin/felix.jar foo</tt>",
it will use "<tt>${user.home}/.felix/foo/</tt>" as the bundle cache directory,
where "<tt>${user.home</tt>}" is automatically substituted with the appropriate
system property by the launcher.</td></tr></table></div>

<p><a name="ApacheFelixFrameworkUsageDocumentation-frameworkshell"></a></p>

<h2><a name="ApacheFelixFrameworkUsageDocumentation-FrameworkShell"></a>Framework
Shell</h2>

<p>The main way to interact with the framework is via the supplied Apache Felix Gogo
shell. After starting the framework, type <tt>help</tt> into the shell to see
the list of the available commands and <tt>help &lt;command-name&gt;</tt>
to get help for a specific command.</p>

<div class='panelMacro'><table class='infoMacro'><colgroup><col width='24'><col></colgroup><tr><td
valign='top'><img src="/confluence/images/icons/emoticons/information.gif" width="16"
height="16" align="absmiddle" alt="" border="0"></td><td><b>Useful Information</b><br
/>In Gogo, command names are made up of two parts: <tt>&lt;scope&gt;:&lt;name&gt;</tt>.
This is similar to a fully qualified class name in Java and is used to avoid naming collisions.
If the <tt>&lt;name&gt;</tt> portion of the command is unique, then you
only need to type it. If not, then you must either type the full <tt>&lt;scope&gt;:&lt;name&gt;</tt>
or arrange the scope search path accordingly.</td></tr></table></div>

<p>To install bundles, use the <tt>felix:install</tt> command, which is
described in more detail in the next <a href="#ApacheFelixFrameworkUsageDocumentation-installingbundles">sub-section</a>.
To list installed bundles, use the <tt>felix:lb</tt> command. To stop the framework
type <tt>stop 0</tt> to stop the System Bundle; any installed bundles will automatically
be reloaded (and potentially restarted) the next time you launch with the associated cache.</p>

<p><a name="ApacheFelixFrameworkUsageDocumentation-installingbundles"></a></p>

<h3><a name="ApacheFelixFrameworkUsageDocumentation-InstallingBundles"></a>Installing
Bundles</h3>

<p>A bundle is the OSGi term for a component for the OSGi framework. A bundle is simply
a JAR file containing a manifest and some combination of Java classes, embedded JAR files,
native code, and resources. A bundle may provide some specific functionality for the user
or it may implement a service that other bundles can use; bundles can only use functionality
from other bundles through shared services and packages.</p>

<p>The Felix framework distribution comes with three bundles, which are located in the
<tt>bundle/</tt> directory of the framework distribution installation directory.
These bundles include the Gogo Runtime (core command processing functionality), Gogo Shell
(text-based shell user interface), Gogo Command (basic set of commands), and Bundle Repository
(a bundle repository service). In addition to these bundles, the bundle repository provides
access to other bundles for easy installation. The bundle repository service provides a set
of shell commands in the <tt>obr:*</tt> scope; refer to the <a href="/confluence/display/FELIX/Apache+Felix+OSGi+Bundle+Repository"
title="Apache Felix OSGi Bundle Repository">Apache Felix OSGi Bundle Repository</a>
for more information.</p>

<p>Before installing any bundles, it is important to understand how bundles are manually
deployed into the framework. Bundles are deployed in two stages; first they are installed,
then they are started. To install a bundle use the <tt>felix:install</tt> shell
command followed by a bundle URL. For example, to install a <tt>bundle.jar</tt>
bundle you type:</p>

<div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent
panelContent">
<pre>felix:install file:/path/to/bundle/bundle.jar
</pre>
</div></div>

<p>Once a bundle is installed, it can then be started by using the <tt>felix:start</tt>
command and the bundle identifier of the desired bundle. The <tt>felix:lb</tt>
command is used to list installed bundles and to obtain the bundle's identifier. The following
Felix shell session illustrates how to start the <tt>bundle.jar</tt> bundle:</p>

<div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent
panelContent">
<pre>g! install file:/path/to/bundle/bundle.jar
g! lb
START LEVEL 1
   ID|State      |Level|Name
    0|Active     |    0|System Bundle (3.0.0)
    1|Active     |    1|Apache Felix Bundle Repository (1.6.2)
    2|Active     |    1|Apache Felix Gogo Command (0.6.0)
    3|Active     |    1|Apache Felix Gogo Runtime (0.6.0)
    4|Active     |    1|Apache Felix Gogo Shell (0.6.0)
    5|Installed  |    1|Example Bundle (1.0.0)
g! start 5
Hello from Bundle 5.
g!
</pre>
</div></div>

<p>The <tt>felix:stop</tt> command is used to stop a bundle and the <tt>felix:uninstall</tt>
command is used to remove a bundle from the bundle cache. As an alternative to using the <tt>felix:install</tt>
and <tt>felix:start</tt> commands explicitly, it is also possible to install and
start a bundle in one step by using the <tt>felix:start</tt> command with a bundle
URL.</p>

<p>Bundles can be updated using the <tt>felix:update</tt> command. The update
command allows you to specify an URL from which to retrieve the updated bundle, but if one
is not specified it will try to update the bundle from the bundle's <tt>Bundle-UpdateLocation</tt>
manifest attribute, if present, or the bundle's original location URL.</p>

<div class='panelMacro'><table class='infoMacro'><colgroup><col width='24'><col></colgroup><tr><td
valign='top'><img src="/confluence/images/icons/emoticons/information.gif" width="16"
height="16" align="absmiddle" alt="" border="0"></td><td><b>Useful Information</b><br
/>When you use <tt>felix:update</tt> or <tt>felix:uninstall</tt>,
the changes appear to take effect immediately, but in reality the changes are only partially
enacted. If a bundle is updated or uninstalled and it was exporting packages, these packages
are not removed until the framework is refreshed using the <tt>PackageAdmin</tt>
service. The Felix shell offers a convenient <tt>refresh</tt> command for this
purpose. This is the correct behavior as defined by the OSGi specification.</td></tr></table></div>

<p>For an introduction to writing bundles and services, refer to the Felix bundle tutorial.</p>

<p><a name="ApacheFelixFrameworkUsageDocumentation-installingbundlesproxies"></a></p>

<h3><a name="ApacheFelixFrameworkUsageDocumentation-WebProxyIssueswhenInstallingBundles"></a>Web
Proxy Issues when Installing Bundles</h3>

<p>If you use a proxy for Web access, then you may run into difficulty using the Gogo
shell to install bundles from remote URLs. To remedy this situation, certain system properties
must be set to make the framework work with your proxy. These properties are:</p>

<ul>
	<li><tt>http.proxyHost</tt> &#45; the name of the proxy host.</li>
	<li><tt>http.proxyPort</tt> &#45; the port of the proxy host.</li>
	<li><tt>http.proxyAuth</tt> &#45; the user name and password to use
when connecting to the proxy; this string should be the user name and password separated by
a colon (e.g., <tt>rickhall:mypassword</tt>).</li>
</ul>


<p>These system properties can be set directly on the command line when starting the
JVM using the standard "<tt>&#45;D&lt;prop&gt;=&lt;value&gt;</tt>"
syntax or you can put them in the <tt>lib/system.properties</tt> file of your
Felix installation; see the next section on <a href="#ApacheFelixFrameworkUsageDocumentation-configuringframework">configuring
Felix</a> for more information.</p>

<p><a name="ApacheFelixFrameworkUsageDocumentation-autodeploy"></a></p>

<h2><a name="ApacheFelixFrameworkUsageDocumentation-BundleAutoDeploy"></a>Bundle
Auto-Deploy</h2>

<p>To minimize the amount of configuration necessary to install bundles when you launch
the framework, the Felix launcher uses the concept of an "auto-deploy" directory. The Felix
launcher deploys all bundles in the auto-deploy directory into the framework instance during
startup. By default, the auto-deploy directory is "<tt>bundle</tt>" in the current
directory, but it can be specified on the command line like this:</p>

<div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent
panelContent">
<pre>java -jar bin/felix.jar -b /path/to/dir
</pre>
</div></div>

<p>Specifying an auto-deploy directory replaces the default directory, it does not augment
it. The framework distribution is configured to install and start bundles in the auto-deploy
directory. Both the location of the auto-deploy directory and the deployment actions performed
can be controlled by the following configuration properties, respectively:</p>

<ul>
	<li><tt>felix.auto.deploy.dir</tt> &#45; Specifies the auto-deploy
directory from which bundles are automatically deploy at framework startup. The default is
the <tt>bundle/</tt> directory of the current directory.</li>
	<li><tt>felix.auto.deploy.action</tt> &#45; Specifies the auto-deploy
actions to be performed on the bundle JAR files found in the auto-deploy directory. The possible
actions are <tt>install</tt>, <tt>update</tt>, <tt>start</tt>,
and <tt>uninstall</tt>. If no actions are specified, then the auto-deploy directory
is not processed (i.e., it is disabled). There is no default value for this property, but
the default <tt>config.properties</tt> file installed with the Felix framework
distribution sets the value to: <tt>install, start</tt></li>
</ul>


<p>The next section describes how to set and use configuration properties.</p>

<p><a name="ApacheFelixFrameworkUsageDocumentation-configuringframework"></a></p>

<h2><a name="ApacheFelixFrameworkUsageDocumentation-ConfiguringtheFramework"></a>Configuring
the Framework</h2>

<p>Both the Felix framework and the launcher use configuration properties to alter their
default behavior. The framework can only be configured by passing properties into its constructor,
but the launcher provides a mechanism to configure the framework via a property file. The
framework launcher reads configuration properties from <tt>conf/config.properties</tt>.
This file uses standard Java property file syntax.</p>

<p>The launcher also supports setting system properties via the <tt>conf/system.properties</tt>
file. This file is purely for convenience when you need to repeatedly set system properties
when running the framework. While the framework itself does not look at system properties,
the launcher does copy any framework configuration properties found in the system properties
into the framework configuration map, also for your convenience.</p>

<p>It is possible to specify different locations for these property files using the
<tt>felix.config.properties</tt> and <tt>felix.system.properties</tt>
system properties when executing the framework. For example:</p>

<div class="preformatted panel" style="border-width: 1px;"><div class="preformattedContent
panelContent">
<pre>java -Dfelix.config.properties=file:/home/rickhall/config.properties -jar bin/felix.jar
</pre>
</div></div>

<p>Configuration and system properties are accessible at run time via <tt>BundleContext.getProperty()</tt>,
but configuration properties override system properties. For more information about available
configuration properties, refer to the <a href="/confluence/display/FELIX/Apache+Felix+Framework+Configuration+Properties"
title="Apache Felix Framework Configuration Properties">Apache Felix Framework Configuration
Properties</a> document. The Felix framework distribution contains a default <tt>conf/config.properties</tt>.</p>

<p><a name="ApacheFelixFrameworkUsageDocumentation-propertysubstitution"></a></p>

<h3><a name="ApacheFelixFrameworkUsageDocumentation-SystemPropertySubstitution"></a>System
Property Substitution</h3>

<p>It is possible to use system properties to specify the values of properties in the
<tt>conf/config.properties</tt> file. This is achieved through system property
substitution, which is instigated by using <tt>${&lt;property&gt;</tt>}
syntax, where <tt>&lt;property&gt;</tt> is the name of a system property
to substitute. When the properties file is read, any such property values are substituted
as appropriate. It is possible to have nested system property substitution, in which case
the inner-most property is substituted first, then the next inner most, until reaching the
outer most.</p>

<p><a name="ApacheFelixFrameworkUsageDocumentation-configuringbundles"></a></p>

<h2><a name="ApacheFelixFrameworkUsageDocumentation-ConfiguringBundles"></a>Configuring
Bundles</h2>

<p>Some bundles use properties to configure certain aspects of their behavior. It is
a good idea, when implementing bundles, to parameterize them with properties where appropriate.
To learn about the configuration options for specific bundles, refer to the documentation
that accompanies them.</p>

<p>Bundle properties may also be defined in the <tt>conf/config.properties</tt>
property file. Any property placed in this file will be accessible via <tt>BundleContext.getProperty()</tt>
at run time. The property file uses the standard Java property file syntax (i.e., attribute-value
pairs). For information on changing the default location of this file, refer to the section
on <a href="#ApacheFelixFrameworkUsageDocumentation-configuringframework">configuring
Felix</a>.</p>

<p><a name="ApacheFelixFrameworkUsageDocumentation-feedback"></a></p>

<h2><a name="ApacheFelixFrameworkUsageDocumentation-Feedback"></a>Feedback</h2>

<p>Subscribe to the Felix users mailing list by sending a message to <a href="mailto:users-subscribe@felix.apache.org"
class="external-link" rel="nofollow">users-subscribe@felix.apache.org</a>; after
subscribing, email questions or feedback to <a href="mailto:users@felix.apache.org" class="external-link"
rel="nofollow">users@felix.apache.org</a>.</p>
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