/* | |
* Licensed to the Apache Software Foundation (ASF) under one | |
* or more contributor license agreements. See the NOTICE file | |
* distributed with this work for additional information | |
* regarding copyright ownership. The ASF licenses this file | |
* to you 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. | |
*/ | |
package org.apache.felix.ipojo.composite.util; | |
import java.util.ArrayList; | |
import java.util.Dictionary; | |
import java.util.List; | |
import org.apache.felix.ipojo.ConfigurationException; | |
import org.apache.felix.ipojo.ContextListener; | |
import org.apache.felix.ipojo.ContextSource; | |
import org.apache.felix.ipojo.composite.CompositeManager; | |
import org.apache.felix.ipojo.parser.ParseUtils; | |
import org.apache.felix.ipojo.util.DependencyModel; | |
import org.apache.felix.ipojo.util.Tracker; | |
import org.apache.felix.ipojo.util.TrackerCustomizer; | |
import org.osgi.framework.BundleContext; | |
import org.osgi.framework.Constants; | |
import org.osgi.framework.Filter; | |
import org.osgi.framework.InvalidSyntaxException; | |
import org.osgi.framework.ServiceReference; | |
/** | |
* This class manages context-source management. | |
* @author <a href="mailto:dev@felix.apache.org">Felix Project Team</a> | |
*/ | |
public class SourceManager implements ContextListener { | |
/** | |
* Source Name service property. | |
*/ | |
public static final String SOURCE_NAME = "source.name"; | |
/** | |
* Managed dependency. | |
*/ | |
private DependencyModel m_dependency; | |
/** | |
* List of monitored context sources. | |
*/ | |
private List/* <ContextSource> */m_sources = new ArrayList(1); | |
/** | |
* PRoperties contained in the original filter. | |
*/ | |
private String[] m_properties; | |
/** | |
* Original filter (containing variables). | |
*/ | |
private String m_filter; | |
/** | |
* Bundle context. | |
*/ | |
private BundleContext m_context; | |
/** | |
* Service Tracker List. | |
*/ | |
private List/*<SourceTracker>*/m_trackers = new ArrayList(1); | |
/** | |
* Constructor. | |
* @param sources : context-source attribute from the dependency metadata | |
* @param depfilter : original dependency filter | |
* @param dependency : dependency object | |
* @param manager : composite manager | |
* @throws ConfigurationException : the sources are incorrect. | |
*/ | |
public SourceManager(String sources, String depfilter, DependencyModel dependency, CompositeManager manager) throws ConfigurationException { | |
m_filter = depfilter; | |
m_properties = getProperties(depfilter); | |
m_dependency = dependency; | |
m_context = manager.getGlobalContext(); | |
if (manager.getParentServiceContext() == null) { | |
// The parent is the global context | |
parseSources(sources, manager.getGlobalContext(), manager.getGlobalContext(), manager.getServiceContext()); | |
} else { | |
parseSources(sources, manager.getGlobalContext(), manager.getParentServiceContext(), manager.getServiceContext()); | |
} | |
} | |
/** | |
* Start the context management. | |
*/ | |
public void start() { | |
for (int i = 0; i < m_trackers.size(); i++) { | |
((SourceTracker) m_trackers.get(i)).open(); | |
} | |
computeFilter(); | |
} | |
/** | |
* Stop the context management. | |
*/ | |
public void stop() { | |
for (int i = 0; i < m_trackers.size(); i++) { | |
((SourceTracker) m_trackers.get(i)).close(); | |
} | |
setFilter(m_filter); | |
m_sources.clear(); | |
} | |
/** | |
* Get the state of this source manager. | |
* @return the state of this source manager. | |
*/ | |
public int getState() { | |
if (m_sources.isEmpty()) { | |
return DependencyModel.UNRESOLVED; | |
} else { | |
return DependencyModel.RESOLVED; | |
} | |
} | |
/** | |
* Set the filter of the managed dependency. | |
* @param filter : the new filter to apply | |
*/ | |
private void setFilter(String filter) { | |
if (!filter.equals(m_dependency.getFilter())) { | |
// Reconfigure | |
try { | |
m_dependency.setFilter(m_context.createFilter(filter)); | |
} catch (InvalidSyntaxException e) { | |
throw new IllegalStateException("A context filter is invalid : " + filter); | |
} | |
} | |
} | |
/** | |
* Compute the new filter. | |
*/ | |
private void computeFilter() { | |
String fil = m_filter; | |
synchronized (this) { | |
for (int i = 0; i < m_sources.size(); i++) { | |
Dictionary props = ((ContextSource) m_sources.get(i)).getContext(); | |
fil = substitute(fil, props); //NOPMD | |
} | |
} | |
if (!fil.equals(m_dependency.getFilter())) { | |
setFilter(fil); | |
} | |
} | |
/** | |
* This method substitute ${var} substring by values stored in a map. | |
* @param str : string with variables | |
* @param values : dictionary containing the variable name and the value. | |
* @return resulted string | |
*/ | |
public static String substitute(String str, Dictionary values) { | |
int len = str.length(); | |
StringBuffer buffer = new StringBuffer(len); | |
int prev = 0; | |
int start = str.indexOf("${"); | |
int end = str.indexOf('}', start); | |
while (start != -1 && end != -1) { | |
String key = str.substring(start + 2, end); | |
Object value = values.get(key); | |
if (value == null) { | |
buffer.append(str.substring(prev, end + 1)); | |
} else { | |
buffer.append(str.substring(prev, start)); | |
buffer.append(value); | |
} | |
prev = end + 1; | |
if (prev >= str.length()) { | |
break; | |
} | |
start = str.indexOf("${", prev); | |
if (start != -1) { | |
end = str.indexOf('}', start); | |
} | |
} | |
buffer.append(str.substring(prev)); | |
return buffer.toString(); | |
} | |
/** | |
* Compute the properties (${name}) from the given filter. | |
* @param str : string form of the filter. | |
* @return the list of found properties. | |
*/ | |
public static String[] getProperties(String str) { | |
List list = new ArrayList(); | |
int prev = 0; | |
int start = str.indexOf("${"); | |
int end = str.indexOf('}', start); | |
while (start != -1 && end != -1) { | |
String key = str.substring(start + 2, end); | |
list.add(key); | |
prev = end + 1; | |
if (prev >= str.length()) { | |
break; | |
} | |
start = str.indexOf("${", prev); | |
if (start != -1) { | |
end = str.indexOf('}', start); | |
} | |
} | |
return (String[]) list.toArray(new String[list.size()]); | |
} | |
/** | |
* A context source has modified a monitored property. | |
* @param source : source | |
* @param property : modified property | |
* @param value : new value. | |
* @see org.apache.felix.ipojo.ContextListener#update(org.apache.felix.ipojo.ContextSource, java.lang.String, java.lang.Object) | |
*/ | |
public synchronized void update(ContextSource source, String property, Object value) { | |
computeFilter(); | |
} | |
/** | |
* Parse the context-source attribute in order to create source tracker object. | |
* @param sourceAtt : context-source attribute. | |
* @param global : global bundle context. | |
* @param parent : parent bundle context. | |
* @param local : local bundle context. | |
* @throws ConfigurationException : the context-source attribute is invalid. | |
*/ | |
private void parseSources(String sourceAtt, BundleContext global, BundleContext parent, BundleContext local) throws ConfigurationException { | |
String[] sources = ParseUtils.split(sourceAtt, ","); | |
for (int i = 0; i < sources.length; i++) { | |
String[] srcs = ParseUtils.split(sources[i], ":"); | |
if (srcs.length == 1) { | |
// No prefix use local. //TODO choose default case. | |
SourceTracker tracker = new SourceTracker(srcs[0], local); | |
m_trackers.add(tracker); | |
} else if (srcs.length == 2) { | |
// According to prefix add the source in the good list. | |
if (srcs[0].equalsIgnoreCase("parent")) { | |
SourceTracker tracker = new SourceTracker(srcs[1], parent); | |
m_trackers.add(tracker); | |
} else if (srcs[0].equalsIgnoreCase("local")) { | |
SourceTracker tracker = new SourceTracker(srcs[1], local); | |
m_trackers.add(tracker); | |
} else if (srcs[0].equalsIgnoreCase("global")) { | |
SourceTracker tracker = new SourceTracker(srcs[1], global); | |
m_trackers.add(tracker); | |
} else { | |
throw new ConfigurationException("Unknowns context scope : " + srcs[0]); | |
} | |
} else { | |
throw new ConfigurationException("Malformed context source : " + sources[i]); | |
} | |
} | |
} | |
/** | |
* A context source appears. | |
* @param source : new context source. | |
*/ | |
private void addContextSource(ContextSource source) { | |
m_sources.add(source); | |
computeFilter(); | |
source.registerContextListener(this, m_properties); | |
} | |
/** | |
* A context source disappears. | |
* @param source : leaving context source. | |
*/ | |
private void removeContextSource(ContextSource source) { | |
m_sources.remove(source); | |
computeFilter(); | |
} | |
private class SourceTracker implements TrackerCustomizer { | |
/** | |
* Service tracker. | |
*/ | |
private Tracker m_tracker; | |
/** | |
* Constructor. | |
* @param name : name of the required context-source. | |
* @param countext : bundle context to use. | |
* @throws ConfigurationException : the context-source name is invalid. | |
*/ | |
public SourceTracker(String name, BundleContext countext) throws ConfigurationException { | |
String fil = "(&(" + Constants.OBJECTCLASS + "=" + ContextSource.class.getName() + ")(" + SOURCE_NAME + "=" + name + "))"; | |
try { | |
Filter filter = countext.createFilter(fil); | |
m_tracker = new Tracker(countext, filter, this); | |
} catch (InvalidSyntaxException e) { | |
throw new ConfigurationException("A Context source filter is invalid " + fil + " : " + e.getMessage()); | |
} | |
} | |
/** | |
* Open the tracker. | |
*/ | |
public void open() { | |
m_tracker.open(); | |
} | |
/** | |
* Close the tracker. | |
*/ | |
public void close() { | |
m_tracker.close(); | |
} | |
/** | |
* A new context-source was added. | |
* This method inject the context-source object in the source manager. | |
* @param reference : service reference. | |
* @see org.apache.felix.ipojo.util.TrackerCustomizer#addedService(org.osgi.framework.ServiceReference) | |
*/ | |
public void addedService(ServiceReference reference) { | |
addContextSource((ContextSource) m_tracker.getService(reference)); | |
} | |
/** | |
* A new context-source is adding in the tracker.. | |
* @param reference : service reference | |
* @return true. | |
* @see org.apache.felix.ipojo.util.TrackerCustomizer#addingService(org.osgi.framework.ServiceReference) | |
*/ | |
public boolean addingService(ServiceReference reference) { | |
return true; | |
} | |
/** | |
* A used context-source is modified. | |
* @param reference : service reference. | |
* @param service : service object. | |
* @see org.apache.felix.ipojo.util.TrackerCustomizer#modifiedService(org.osgi.framework.ServiceReference, java.lang.Object) | |
*/ | |
public void modifiedService(ServiceReference reference, Object service) { | |
// Nothing to do. | |
} | |
/** | |
* A used context-source disappears. | |
* This method notify the Source Manager in order to manage this departure. | |
* @param reference : service reference. | |
* @param service : service object. | |
* @see org.apache.felix.ipojo.util.TrackerCustomizer#modifiedService(org.osgi.framework.ServiceReference, java.lang.Object) | |
*/ | |
public void removedService(ServiceReference reference, Object service) { | |
removeContextSource((ContextSource) service); | |
} | |
} | |
} |