Index: conf/testConfigurationProvider.xml =================================================================== --- conf/testConfigurationProvider.xml (revision 0) +++ conf/testConfigurationProvider.xml (revision 0) @@ -0,0 +1,37 @@ + + + +
+ + + + + + + + + + + table + list + + + +
+ + + + + + + + + + --> + + + \ No newline at end of file Index: conf/testExtendedClass.xml =================================================================== --- conf/testExtendedClass.xml (revision 0) +++ conf/testExtendedClass.xml (revision 0) @@ -0,0 +1,34 @@ + + + +
+ + + + + + + + table + list + + + +
+ + + + + + + + + + --> + + + \ No newline at end of file Index: src/test/org/apache/commons/configuration/TestDefaultConfigurationBuilder.java =================================================================== --- src/test/org/apache/commons/configuration/TestDefaultConfigurationBuilder.java (revision 695569) +++ src/test/org/apache/commons/configuration/TestDefaultConfigurationBuilder.java (working copy) @@ -32,7 +32,7 @@ * Test class for DefaultConfigurationBuilder. * * @author Oliver Heger - * @version $Id$ + * @version $Id: TestDefaultConfigurationBuilder.java 578455 2007-09-22 15:12:16Z oheger $ */ public class TestDefaultConfigurationBuilder extends TestCase { @@ -55,6 +55,12 @@ private static final File INIT_FILE = new File( "conf/testComplexInitialization.xml"); + private static final File CLASS_FILE = new File( + "conf/testExtendedClass.xml"); + + private static final File PROVIDER_FILE = new File( + "conf/testConfigurationProvider.xml"); + /** Constant for the name of an optional configuration.*/ private static final String OPTIONAL_NAME = "optionalConfig"; @@ -743,4 +749,33 @@ testSavedXML.delete(); testSavedFactory.delete(); } + + public void testExtendedClass() throws ConfigurationException, IOException + { + DefaultConfigurationBuilder builder = new DefaultConfigurationBuilder(); + builder.setFile(CLASS_FILE); + CombinedConfiguration cc = builder.getConfiguration(true); + assertEquals("Extended", cc.getProperty("test")); + } + + public void testConfigurationProvider() throws ConfigurationException, IOException + { + DefaultConfigurationBuilder builder = new DefaultConfigurationBuilder(); + builder.setFile(PROVIDER_FILE); + CombinedConfiguration cc = builder.getConfiguration(true); + DefaultConfigurationBuilder.ConfigurationProvider provider = builder.providerForTag("test"); + assertNotNull("Provider 'test' not registered", provider); + } + + public static class ExtendedCombinedConfiguration extends CombinedConfiguration + { + public Object getProperty(String key) + { + if (key.equals("test")) + { + return "Extended"; + } + return super.getProperty(key); + } + } } Index: src/java/org/apache/commons/configuration/DefaultConfigurationBuilder.java =================================================================== --- src/java/org/apache/commons/configuration/DefaultConfigurationBuilder.java (revision 701606) +++ src/java/org/apache/commons/configuration/DefaultConfigurationBuilder.java (working copy) @@ -137,7 +137,7 @@ * the resulting configuration. *

*

- * The configuration object returned by this builder is an instance of the + * The default configuration object returned by this builder is an instance of the * {@link CombinedConfiguration} class. The return value of the * getConfiguration() method can be casted to this type, and the * getConfiguration(boolean) method directly declares @@ -146,9 +146,20 @@ * configuration (e.g. for updates of single configuration objects). It has also * the advantage that the properties stored in all declared configuration * objects are collected and transformed into a single hierarchical structure, - * which can be accessed using different expression engines. + * which can be accessed using different expression engines. The actual CombinedConfiguration + * implementation can be overridden by specifying the class in the config-class + * attribute of the result element. *

*

+ * Additional ConfigurationProviders can be added by configuring them in the header + * section. + * 

+ * <providers>
+ *   <provider config-tag="tag name" config-class="provider fully qualifed class name"/>
+ * </providers>
+ *
+ *

+ *

* All declared override configurations are directly added to the resulting * combined configuration. If they are given names (using the * config-name attribute), they can directly be accessed using @@ -268,6 +279,11 @@ static final String KEY_ADDITIONAL_LIST = SEC_HEADER + ".combiner.additional.list-nodes.node"; + static final String KEY_CONFIGURATION_PROVIDERS = SEC_HEADER + + ".providers.provider"; + + static final String KEY_PROVIDER_KEY = XMLBeanDeclaration.ATTR_PREFIX + "tag]"; + /** * Constant for the key of the result declaration. This key can point to a * bean declaration, which defines properties of the resulting combined @@ -493,6 +509,8 @@ load(); } + registerConfiguredProviders(); + CombinedConfiguration result = createResultConfiguration(); constructedConfiguration = result; @@ -528,8 +546,23 @@ throws ConfigurationException { XMLBeanDeclaration decl = new XMLBeanDeclaration(this, KEY_RESULT, true); - CombinedConfiguration result = (CombinedConfiguration) BeanHelper - .createBean(decl, CombinedConfiguration.class); + Class clazz; + if (decl.getBeanClassName() != null) + { + try + { + clazz = Class.forName(decl.getBeanClassName()) ; + } + catch (ClassNotFoundException cnfe) + { + throw new ConfigurationException("Unable to locate class " + decl.getBeanClassName(), cnfe); + } + } + else + { + clazz = CombinedConfiguration.class; + } + CombinedConfiguration result = (CombinedConfiguration) BeanHelper.createBean(decl, clazz); if (getMaxIndex(KEY_COMBINER) < 0) { @@ -589,6 +622,33 @@ } /** + * Registers providers defined in the configuration. + * @throws ConfigurationException if an error occurs + */ + protected void registerConfiguredProviders() throws ConfigurationException + { + List nodes = configurationsAt(KEY_CONFIGURATION_PROVIDERS); + for (Iterator it = nodes.iterator(); it.hasNext();) + { + HierarchicalConfiguration config = (HierarchicalConfiguration)it.next(); + XMLBeanDeclaration decl = new XMLBeanDeclaration(config); + String key = config.getString(KEY_PROVIDER_KEY); + String className = decl.getBeanClassName(); + ConfigurationProvider provider; + try + { + Class providerClass = Class.forName(className) ; + provider = (ConfigurationProvider) BeanHelper.createBean(decl, providerClass); + } + catch (Exception cnfe) + { + throw new ConfigurationException("Unable to create configuration provider " + className, cnfe); + } + addConfigurationProvider(key, provider); + } + } + + /** * Performs interpolation. This method will not only take this configuration * instance into account (which is the one that loaded the configuration * definition file), but also the so far constructed combined configuration.