org.apache.commons.discovery.tools

Class ResourceUtils

public class ResourceUtils extends Object

Mechanisms to locate and load a class. The load methods locate a class only. The find methods locate a class and verify that the class implements an given interface or extends a given class.

Author: Richard A. Sitze Craig R. McClanahan Costin Manolache

Method Summary
static StringgetPackageName(Class clazz)
Get package name.
static ResourcegetResource(Class spi, String resourceName, ClassLoaders loaders)
Load the resource resourceName.
static PropertiesloadProperties(Class spi, String propertiesFileName, ClassLoaders classLoaders)
Load named property file, optionally qualifed by spi's package name as per Class.getResource.

Method Detail

getPackageName

public static String getPackageName(Class clazz)
Get package name. Not all class loaders 'keep' package information, in which case Class.getPackage() returns null. This means that calling Class.getPackage().getName() is unreliable at best.

getResource

public static Resource getResource(Class spi, String resourceName, ClassLoaders loaders)
Load the resource resourceName. Try each classloader in succession, until first succeeds, or all fail. If all fail and resouceName is not absolute (doesn't start with '/' character), then retry with packageName/resourceName after changing all '.' to '/'.

Parameters: resourceName The name of the resource to load.

loadProperties

public static Properties loadProperties(Class spi, String propertiesFileName, ClassLoaders classLoaders)
Load named property file, optionally qualifed by spi's package name as per Class.getResource. A property file is loaded using the following sequence of class loaders:

Parameters: propertiesFileName The property file name.

Returns: Instance of a class implementing the SPI.

Throws: DiscoveryException Thrown if the name of a class implementing the SPI cannot be found, if the class cannot be loaded and instantiated, or if the resulting class does not implement (or extend) the SPI.

UNKNOWN:

Copyright (c) 2002 - Apache Software Foundation