org.neo4j.upgrade.loader

Class EmbeddedJarLoader

java.lang.Object

org.neo4j.upgrade.loader.EmbeddedJarLoader

All Implemented Interfaces:

AutoCloseable

public class EmbeddedJarLoader
extends Object
implements AutoCloseable

Loader that will try to load jar that is embedded into some other jar.

In case if we do not want jar file to be visible for classloaders we can embed it into other jar as resource. This loaded will allow us to use those jars later on and will provide facility to load classes from them.

Please note that this class should not be used as a generic class loader. Example use case: ability to ship several versions of artifact for migration purposes (lucene indexes migrator as example)

Method Summary

Modifier and Type	Method and Description
void	close() Release class loader that was used for class loading and attempt to delete all extracted jars.
ClassLoader	getJarsClassLoader() Get class loaded of embedded jar files
Class	loadEmbeddedClass(String className) Load class from embedded jar

Methods inherited from class java.lang.Object

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

Method Detail

loadEmbeddedClass

public Class loadEmbeddedClass(String className)
                        throws ClassNotFoundException,
                               IOException

Load class from embedded jar

Parameters:

className - fully qualified class name

Returns:

Loaded class

Throws:

ClassNotFoundException - in case if specified class not found

IOException - if class cannot be extracted

getJarsClassLoader

public ClassLoader getJarsClassLoader()
                               throws IOException

Get class loaded of embedded jar files

Returns:

jar files class loader

Throws:

IOException - if exception occurred during class loader construction

close

public void close()
           throws IOException

Release class loader that was used for class loading and attempt to delete all extracted jars. If deletion will not succeed, they will be deleted on JVM exit.

Specified by:

close in interface AutoCloseable

Throws:

IOException