Package org.eclipse.jetty.osgi.boot.internal.webapp

Class LibExtClassLoaderHelper

java.lang.Object

org.eclipse.jetty.osgi.boot.internal.webapp.LibExtClassLoaderHelper

public class LibExtClassLoaderHelper
extends Object

LibExtClassLoaderHelper

Helper to create a URL class-loader with the jars inside ${jetty.home}/lib/ext and ${jetty.home}/resources. In an ideal world, every library is an OSGi bundle that does loads nicely. To support standard jars or bundles that cannot be loaded in the current OSGi environment, we support inserting the jars in the usual jetty/lib/ext folders in the proper classpath for the webapps.

The drawback is that those jars will not be available in the OSGi classloader.

Alternatives to placing jars in lib/ext:

1. Bundle the jars in an osgi bundle. Have the webapp(s) that need these jars depend on that bundle.
2. Bundle those jars in an osgi bundle-fragment that targets the jetty-bootstrap bundle
3. Use equinox Buddy-Policy: register a buddy of the jetty bootstrapper bundle. (Note: it will work only on equinox)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	LibExtClassLoaderHelper.IFilesInJettyHomeResourcesProcessor	IFilesInJettyHomeResourcesProcessor Interface for callback impls

Field Summary

Fields

Modifier and Type	Field	Description
static final Set<LibExtClassLoaderHelper.IFilesInJettyHomeResourcesProcessor>	registeredFilesInJettyHomeResourcesProcessors

Constructor Summary

Constructors

Constructor	Description
LibExtClassLoaderHelper()

Method Summary

Modifier and Type	Method	Description
static ClassLoader	createLibEtcClassLoader(File jettyHome, ClassLoader parentClassLoader)
static ClassLoader	createLibExtClassLoader(List<File> jarsContainerOrJars, List<URL> otherJarsOrFolder, ClassLoader parentClassLoader)
protected static void	processFilesInResourcesFolder(File jettyHome, Map<String,File> childrenFiles)	When we find files typically used for central logging configuration we do what it takes in this method to do what the user expects.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

registeredFilesInJettyHomeResourcesProcessors

public static final Set<LibExtClassLoaderHelper.IFilesInJettyHomeResourcesProcessor> registeredFilesInJettyHomeResourcesProcessors

Constructor Details

LibExtClassLoaderHelper

public LibExtClassLoaderHelper()

Method Details

createLibEtcClassLoader

public static ClassLoader createLibEtcClassLoader(File jettyHome,
 ClassLoader parentClassLoader)
                                           throws MalformedURLException

Parameters:

jettyHome - the jetty home

parentClassLoader - the parent classloader

Returns:

a url classloader with the jars of resources, lib/ext and the jars passed in the other argument. The parent classloader usually is the JettyBootStrapper (an osgi classloader.

Throws:

MalformedURLException - if the jetty home reference is invalid

createLibExtClassLoader

public static ClassLoader createLibExtClassLoader(List<File> jarsContainerOrJars,
 List<URL> otherJarsOrFolder,
 ClassLoader parentClassLoader)
                                           throws MalformedURLException

Parameters:

jarsContainerOrJars - the jars via file references

otherJarsOrFolder - more jars via url references

parentClassLoader - the parent classloader

Returns:

a url classloader with the jars of resources, lib/ext and the jars passed in the other argument. The parent classloader usually is the JettyBootStrapper (an osgi classloader). If there was no extra jars to insert, then just return the parentClassLoader.

Throws:

MalformedURLException - if there is a bad jar file reference

processFilesInResourcesFolder

protected static void processFilesInResourcesFolder(File jettyHome,
 Map<String,File> childrenFiles)

When we find files typically used for central logging configuration we do what it takes in this method to do what the user expects. Without depending too much directly on a particular logging framework.

We can afford to do some implementation specific code for a logging framework only in a fragment.

Trying to configure log4j and logback in here.

We recommend that slf4j jars are all placed in the osgi framework. And a single implementation if possible packaged as an osgi bundle is there.

Parameters:

jettyHome - the jetty home reference

childrenFiles - the map of child files