/*
* #%L
* BroadleafCommerce Common Libraries
* %%
* Copyright (C) 2009 - 2013 Broadleaf Commerce
* %%
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* #L%
*/
package org.broadleafcommerce.common.extensibility.context;
import org.broadleafcommerce.common.extensibility.context.merge.ImportProcessor;
import org.broadleafcommerce.common.extensibility.context.merge.exceptions.MergeException;
import org.springframework.beans.BeansException;
import org.springframework.beans.FatalBeanException;
import org.springframework.context.ApplicationContext;
/**
* Standalone XML application context, taking the locations of one or more
* source applicationContext xml files and one or more patch xml files.
*
* <p>One or more source files merge together in pure override mode. Source
* files are merged in the order specified. If a bean id is repeated in a subsequent
* source file, the subsequent bean definition will always win. This is the same behavior
* as Spring's default mechanism for merging 1 to N applicationContext files.</p>
*
* <p>Each patch file is merged with the combined source, one patch file at a time. This
* merge is performed in true merge mode. Therefore, if a bean id is delivered in a patch
* file with the same id as a bean in the source, the patch will merge with the source. This
* could result in an override of the class definition for the bean, or additional or changed
* property elements within the bean definition.</p>
*
* @author jfischer
*
*/
public class MergeClassPathXMLApplicationContext extends AbstractMergeXMLApplicationContext {
public MergeClassPathXMLApplicationContext(ApplicationContext parent) {
super(parent);
}
/**
* Create a new MergeClassPathXMLApplicationContext, loading the definitions from the given definitions. Note,
* all sourceLocation files will be merged using standard Spring configuration override rules. However, the patch
* files are fully merged into the result of the sourceLocations simple merge. Patch merges are first executed according
* to beans with the same id. Subsequent merges within a bean are executed against tagnames - ignoring any
* further id attributes.
*
* @param sourceLocations array of relative (or absolute) paths within the class path for the source application context files
* @param patchLocations array of relative (or absolute) paths within the class path for the patch application context files
* @throws BeansException
*/
public MergeClassPathXMLApplicationContext(String[] sourceLocations, String[] patchLocations) throws BeansException {
this(sourceLocations, patchLocations, null);
}
/**
* Create a new MergeClassPathXMLApplicationContext, loading the definitions from the given definitions. Note,
* all sourceLocation files will be merged using standard Spring configuration override rules. However, the patch
* files are fully merged into the result of the sourceLocations simple merge. Patch merges are first executed according
* to beans with the same id. Subsequent merges within a bean are executed against tagnames - ignoring any
* further id attributes.
*
* @param sourceLocations array of relative (or absolute) paths within the class path for the source application context files
* @param patchLocations array of relative (or absolute) paths within the class path for the patch application context files
* @param parent the parent context
* @throws BeansException
*/
public MergeClassPathXMLApplicationContext(String[] sourceLocations, String[] patchLocations, ApplicationContext parent) throws BeansException {
this(parent);
ResourceInputStream[] sources = new ResourceInputStream[sourceLocations.length];
for (int j=0;j<sourceLocations.length;j++){
sources[j] = new ResourceInputStream(getClassLoader(parent).getResourceAsStream(sourceLocations[j]), sourceLocations[j]);
}
ResourceInputStream[] patches = new ResourceInputStream[patchLocations.length];
for (int j=0;j<patches.length;j++){
patches[j] = new ResourceInputStream(getClassLoader(parent).getResourceAsStream(patchLocations[j]), patchLocations[j]);
}
ImportProcessor importProcessor = new ImportProcessor(this);
try {
sources = importProcessor.extract(sources);
patches = importProcessor.extract(patches);
} catch (MergeException e) {
throw new FatalBeanException("Unable to merge source and patch locations", e);
}
this.configResources = new MergeApplicationContextXmlConfigResource().getConfigResources(sources, patches);
refresh();
}
/**
* This could be advantageous for subclasses to override in order to utilize the parent application context. By default,
* this utilizes the class loader for the current class.
*/
protected ClassLoader getClassLoader(ApplicationContext parent) {
return MergeClassPathXMLApplicationContext.class.getClassLoader();
}
}