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Posted to commits@tamaya.apache.org by pl...@apache.org on 2016/09/25 21:35:47 UTC

[07/23] incubator-tamaya-sandbox git commit: TAMAYA-123: Adding OSGI Support: had to move some aspects out of (non-accessible) internal packages.

TAMAYA-123: Adding OSGI Support: had to move some aspects out of (non-accessible) internal packages.


Project: http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/repo
Commit: http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/commit/03a58b64
Tree: http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/tree/03a58b64
Diff: http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/diff/03a58b64

Branch: refs/heads/master
Commit: 03a58b64c0ed6093d375e37455618e1bfae0b1bb
Parents: e441ee7
Author: anatole <an...@apache.org>
Authored: Fri Oct 16 19:33:48 2015 +0200
Committer: anatole <an...@apache.org>
Committed: Fri Oct 16 19:33:48 2015 +0200

----------------------------------------------------------------------
 .../clsupport/CLAwareConfigurationContext.java  | 105 +++++++
 .../tamaya/clsupport/CLAwareServiceContext.java | 246 +++++++++++++++
 .../tamaya/clsupport/ServiceContainer.java      | 311 +++++++++++++++++++
 .../internal/CLAwareConfigurationContext.java   | 106 -------
 .../internal/CLAwareServiceContext.java         | 247 ---------------
 .../clsupport/internal/ServiceContainer.java    | 311 -------------------
 .../tamaya/clsupport/internal/package-info.java |  22 --
 .../org.apache.tamaya.spi.ServiceContext        |   2 +-
 8 files changed, 663 insertions(+), 687 deletions(-)
----------------------------------------------------------------------


http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/blob/03a58b64/src/main/java/org/apache/tamaya/clsupport/CLAwareConfigurationContext.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/tamaya/clsupport/CLAwareConfigurationContext.java b/src/main/java/org/apache/tamaya/clsupport/CLAwareConfigurationContext.java
new file mode 100644
index 0000000..47b78b2
--- /dev/null
+++ b/src/main/java/org/apache/tamaya/clsupport/CLAwareConfigurationContext.java
@@ -0,0 +1,105 @@
+/*
+ * 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.tamaya.clsupport;
+
+import org.apache.tamaya.TypeLiteral;
+import org.apache.tamaya.spisupport.DefaultConfigurationContext;
+import org.apache.tamaya.spi.ConfigurationContext;
+import org.apache.tamaya.spi.ConfigurationContextBuilder;
+import org.apache.tamaya.spi.PropertyConverter;
+import org.apache.tamaya.spi.PropertyFilter;
+import org.apache.tamaya.spi.PropertySource;
+import org.apache.tamaya.spi.PropertyValueCombinationPolicy;
+
+import javax.annotation.Priority;
+import java.util.List;
+import java.util.Map;
+import java.util.logging.Logger;
+
+/**
+ * Default Implementation of a simple ConfigurationContext.
+ */
+@Priority(100)
+public class CLAwareConfigurationContext implements ConfigurationContext {
+
+    /** The logger used. */
+    private final static Logger LOG = Logger.getLogger(CLAwareConfigurationContext.class.getName());
+
+    private ContextManager contextManager = new ContextManager();
+
+
+    @Override
+    public void addPropertySources(PropertySource... propertySourcesToAdd) {
+        contextManager.getItemNoParent(true).addPropertySources(propertySourcesToAdd);
+    }
+
+    @Override
+    public List<PropertySource> getPropertySources() {
+        return contextManager.getItemNoParent(true).getPropertySources();
+    }
+
+    @Override
+    public <T> void addPropertyConverter(TypeLiteral<T> typeToConvert, PropertyConverter<T> propertyConverter) {
+        contextManager.getItemNoParent(true).addPropertyConverter(typeToConvert, propertyConverter);
+    }
+
+    @Override
+    public Map<TypeLiteral<?>, List<PropertyConverter<?>>> getPropertyConverters() {
+        return contextManager.getItemNoParent(true).getPropertyConverters();
+    }
+
+    @Override
+    public <T> List<PropertyConverter<T>> getPropertyConverters(TypeLiteral<T> targetType) {
+        return contextManager.getItemNoParent(true).getPropertyConverters(targetType);
+    }
+
+    @Override
+    public List<PropertyFilter> getPropertyFilters() {
+        return contextManager.getItemNoParent(true).getPropertyFilters();
+    }
+
+    @Override
+    public PropertyValueCombinationPolicy getPropertyValueCombinationPolicy(){
+        return contextManager.getItemNoParent(true).getPropertyValueCombinationPolicy();
+    }
+
+    @Override
+    public ConfigurationContextBuilder toBuilder() {
+        return contextManager.getItemNoParent(true).toBuilder();
+    }
+
+
+    /**
+     * Subcomponent managing {@link ConfigurationContext} instances, one per classloader.
+     */
+    private static final class ContextManager extends AbstractClassloaderAwareItemLoader<ConfigurationContext>{
+
+        @Override
+        protected ConfigurationContext createItem(ClassLoader classLoader) {
+            // Simply create a complete configuration manager for every classloader. Maybe we will optimize this at a
+            // later stage in the project but as for now it is the most simple working solution.
+            return new DefaultConfigurationContext();
+        }
+
+        @Override
+        protected void updateItem(ConfigurationContext currentItemSet, ClassLoader classLoader) {
+            // ignore, currently not supported.
+        }
+    }
+}

http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/blob/03a58b64/src/main/java/org/apache/tamaya/clsupport/CLAwareServiceContext.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/tamaya/clsupport/CLAwareServiceContext.java b/src/main/java/org/apache/tamaya/clsupport/CLAwareServiceContext.java
new file mode 100644
index 0000000..392d8b1
--- /dev/null
+++ b/src/main/java/org/apache/tamaya/clsupport/CLAwareServiceContext.java
@@ -0,0 +1,246 @@
+/*
+ * 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.tamaya.clsupport;
+
+import org.apache.tamaya.ConfigException;
+import org.apache.tamaya.spi.ServiceContext;
+
+import javax.annotation.Priority;
+import java.text.MessageFormat;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+
+/**
+ * This class implements a {@link ServiceContext}, which basically provides a similar loading mechanism as used
+ * by the {@link java.util.ServiceLoader}. Whereas the {@link java.util.ServiceLoader} only loads configurations
+ * and instances from one classloader, this loader manages configs found and the related instances for each
+ * classloader along the classloader hierarchies individually. It ensures instances are loaded on the classloader
+ * level, where they first are visible. Additionally it ensures the same configuration resource (and its
+ * declared services) are loaded multiple times, when going up the classloader hierarchy.<p/>
+ * Finally classloaders are not stored by reference by this class, to ensure they still can be garbage collected.
+ * Refer also the inherited parent class for further details.<p/>
+ * This class uses an ordinal of {@code 10}, so it overrides any default {@link ServiceContext} implementations
+ * provided with the Tamaya core modules.
+ */
+@Priority(10)
+public class CLAwareServiceContext extends AbstractClassloaderAwareItemLoader<ServiceContainer>
+        implements ServiceContext{
+
+    private static final Logger LOG = Logger.getLogger(CLAwareServiceContext.class.getName());
+
+    /**
+     * Default location for service loader files.
+     */
+    private static final String PREFIX = "META-INF/services/";
+
+    /**
+     * Constructor, using the current default classloader as defined by
+     * {@link AbstractClassloaderAwareItemLoader#getDefaultClassLoader()}.
+     */
+    public CLAwareServiceContext(){
+        super();
+    }
+
+    /**
+     * Constructor, using the given classloader.
+     * @param classLoader the target classloader for initializing of services, not null.
+     */
+    public CLAwareServiceContext(ClassLoader classLoader) {
+        super(classLoader);
+    }
+
+
+    /**
+     * Implementation that creates a {@link ServiceContainer}, which manages all configs and instances loaded
+     * for a given classloader.
+     * @param classLoader the classloader, not null.
+     * @return a new empty, {@link ServiceContainer} instance.
+     */
+    @Override
+    protected ServiceContainer createItem(ClassLoader classLoader) {
+        if(LOG.isLoggable(Level.INFO)) {
+            LOG.info("Loading services for classloader: " + classLoader);
+        }
+        return new ServiceContainer(classLoader);
+    }
+
+    @Override
+    protected void updateItem(ServiceContainer currentContainer, ClassLoader classLoader) {
+        // nothing to be done here, since we dont have a specific target type.
+    }
+
+    @Override
+    public int ordinal() {
+        return 10;
+    }
+
+    /**
+     * This method tries to evaluate the current singleton from the {@link ServiceContainer} attached to the
+     * current classloader. If not found the singleton instance is evaluated based on the priorities
+     * assigned for all known providers. The resulting instance is then cached and always returned as
+     * singleton instance fomr this loader, when the same current classloader instance is active.
+     * @param serviceType the service type.
+     * @param <T> the type
+     * @return the item found, or null.
+     */
+    @Override
+    public <T> T getService(Class<T> serviceType) {
+        return getService(serviceType, getDefaultClassLoader());
+    }
+
+    /**
+     * Evaluates the current singleton instance using the given classloader context.
+     * @param serviceType the service type.
+     * @param classLoader the classloader, not null.
+     * @param <T> the type
+     * @return the item found, or null.
+     */
+    public <T> T getService(Class<T> serviceType, ClassLoader classLoader) {
+        if(LOG.isLoggable(Level.INFO)) {
+            LOG.info("Evaluating services for classloader: " + classLoader);
+        }
+        ServiceContainer container = getItemNoParent(classLoader, true);
+        T singleton = container.getSingleton(serviceType);
+        if(singleton!=null){
+            if(LOG.isLoggable(Level.FINEST)) {
+                LOG.finest("Evaluated singleton of type " + serviceType.getName() + " to " + singleton);
+            }
+            return singleton;
+        }
+        Collection<? extends T> services = getServices(serviceType, classLoader);
+        if (services.isEmpty()) {
+            singleton = null;
+        } else {
+            singleton = getServiceWithHighestPriority(services, serviceType);
+        }
+        if(singleton!=null) {
+            container.setSingleton(serviceType, singleton);
+        }
+        if(LOG.isLoggable(Level.FINEST)) {
+            LOG.finest("Evaluated singleton of type " + serviceType.getName() + " to " + singleton);
+        }
+        return singleton;
+    }
+
+    /**
+     * Gets the services visible.
+     * @param serviceType
+     *            the service type.
+     * @param <T> the type param
+     * @return the services visible for the current classloader.
+     */
+    @Override
+    public <T> List<T> getServices(Class<T> serviceType) {
+        return getServices(serviceType, AbstractClassloaderAwareItemLoader.getDefaultClassLoader());
+    }
+
+    /**
+     * Gets the services visible.
+     * @param serviceType the service type.
+     * @param classLoader the classloader
+     * @param <T> the type param
+     * @return the services visible for the current classloader.
+     */
+    public <T> List<T> getServices(Class<T> serviceType, ClassLoader classLoader) {
+        List<T> services = new ArrayList<>();
+        ClassLoader cl = classLoader;
+        List<ServiceContainer> containers = new ArrayList<>();
+        while(cl!=null) {
+            ServiceContainer container = getItemNoParent(cl, true);
+            containers.add(container);
+            cl = cl.getParent();
+        }
+        List<ServiceContainer> prevContainers = new ArrayList<>();
+        Collections.reverse(containers);
+        for(ServiceContainer container: containers) {
+            if (!container.isTypeLoaded(serviceType)) {
+                container.loadServices(serviceType, prevContainers);
+            }
+            services.addAll(container.getServices(serviceType));
+            prevContainers.add(container);
+        }
+        if(LOG.isLoggable(Level.FINEST)) {
+            LOG.finest("Evaluated services of type " + serviceType.getName() + " to " + services);
+        }
+        return services;
+    }
+
+    /**
+     * @param services to scan
+     * @param <T>      type of the service
+     *
+     * @return the service with the highest {@link javax.annotation.Priority#value()}
+     *
+     * @throws ConfigException if there are multiple service implementations with the maximum priority
+     */
+    private <T> T getServiceWithHighestPriority(Collection<? extends T> services, Class<T> serviceType) {
+
+        // we do not need the priority stuff if the list contains only one element
+        if (services.size() == 1) {
+            return services.iterator().next();
+        }
+
+        Integer highestPriority = null;
+        int highestPriorityServiceCount = 0;
+        T highestService = null;
+
+        for (T service : services) {
+            int prio = getPriority(service);
+            if (highestPriority == null || highestPriority < prio) {
+                highestService = service;
+                highestPriorityServiceCount = 1;
+                highestPriority = prio;
+            } else if (highestPriority == prio) {
+                highestPriorityServiceCount++;
+            }
+        }
+        if (highestPriorityServiceCount > 1) {
+            throw new ConfigException(MessageFormat.format("Found {0} implementations for Service {1} with Priority {2}: {3}",
+                    highestPriorityServiceCount,
+                    serviceType.getName(),
+                    highestPriority,
+                    services));
+        }
+        return highestService;
+    }
+
+    /**
+     * Checks the given instance for a @Priority annotation. If present the annotation's value s evaluated. If no such
+     * annotation is present, a default priority is returned (1);
+     * @param o the instance, not null.
+     * @return a priority, by default 1.
+     */
+    public static int getPriority(Object o){
+        int prio = 0;
+        Priority priority = o.getClass().getAnnotation(Priority.class);
+        if (priority != null) {
+            prio = priority.value();
+        }
+        if(LOG.isLoggable(Level.FINEST)) {
+            LOG.finest("Evaluated priority for " + o.getClass().getName() + " to " + prio);
+        }
+        return prio;
+    }
+
+}

http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/blob/03a58b64/src/main/java/org/apache/tamaya/clsupport/ServiceContainer.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/tamaya/clsupport/ServiceContainer.java b/src/main/java/org/apache/tamaya/clsupport/ServiceContainer.java
new file mode 100644
index 0000000..1eea749
--- /dev/null
+++ b/src/main/java/org/apache/tamaya/clsupport/ServiceContainer.java
@@ -0,0 +1,311 @@
+/*
+ * 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.tamaya.clsupport;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.lang.ref.WeakReference;
+import java.net.URL;
+import java.security.AccessControlContext;
+import java.security.AccessController;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Enumeration;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.ServiceConfigurationError;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+/**
+ * Created by Anatole on 08.09.2015.
+ */
+class ServiceContainer {
+
+    private static final Logger LOG = Logger.getLogger(ServiceContainer.class.getName());
+
+    private static final String PREFIX = "META-INF/services/";
+
+    // The access control context taken when the ServiceLoader is created
+    private final AccessControlContext acc;
+
+    private WeakReference<ClassLoader> classLoaderRef;
+
+    /**
+     * List current services loaded using this classloader, per class.
+     */
+    private final Map<Class<?>, Map<String, Object>> servicesLoaded = new ConcurrentHashMap<>();
+    /**
+     * The cached singletons for the given classloader.
+     */
+    private final Map<Class, Object> singletons = new ConcurrentHashMap<>();
+
+    /**
+     * List current services loaded using this classloader, per class.
+     */
+    private final Map<Class, List<URL>> configsLoaded = new ConcurrentHashMap<>();
+
+    ServiceContainer(ClassLoader classLoader) {
+        acc = (System.getSecurityManager() != null) ? AccessController.getContext() : null;
+        this.classLoaderRef = new WeakReference<>(classLoader);
+    }
+
+    public ClassLoader getClassLoader() {
+        ClassLoader cl = classLoaderRef.get();
+        if (cl == null) {
+            throw new IllegalStateException("Classloader reference removed, not active anynire.");
+        }
+        return cl;
+    }
+
+
+    public <T> void loadServices(Class<?> type,
+                                 Collection<ServiceContainer> preceedingContainers) {
+        Map<String, Object> services = (Map<String, Object>) this.servicesLoaded.get(type);
+        if (services == null) {
+            services = new LinkedHashMap<>();
+            this.servicesLoaded.put(type, services);
+        }
+        loop:
+        for (URL config : getConfigs(type)) {
+            for (ServiceContainer cont : preceedingContainers) {
+                if (cont.getConfigs(type).contains(config)) {
+                    LOG.finer("Ignoring already loaded config: " + config);
+                    continue loop;
+                }
+            }
+            Collection<String> serviceNames = parse(type, config);
+            for (String s : serviceNames) {
+                for (ServiceContainer cont : preceedingContainers) {
+                    if (cont.containsService(type, s)) {
+                        LOG.finest("Ignoring duplicate service: " + s);
+                        continue;
+                    }
+                }
+                LOG.info("Loading component: " + s);
+                services.put(s, create(type, s));
+            }
+        }
+    }
+
+    private Collection<URL> getConfigs(Class<?> type) {
+        List<URL> result = this.configsLoaded.get(type);
+        if (result == null) {
+            ClassLoader cl = this.classLoaderRef.get();
+            if (cl == null) {
+                throw new IllegalStateException("CLassLoader dereferenced already.");
+            }
+            result = new ArrayList<>();
+            try {
+                Enumeration<URL> resources = cl.getResources(PREFIX + type.getName());
+                while (resources.hasMoreElements()) {
+                    result.add(resources.nextElement());
+                }
+            } catch (Exception e) {
+                LOG.log(Level.WARNING, "Failed to read service config for " + type.getName() + " from " + cl, e);
+            }
+            this.configsLoaded.put(type, result);
+            LOG.log(Level.FINE, "Found service config for " + type.getName() + ": " + result);
+        }
+        return result;
+    }
+
+    private boolean containsService(Class<?> type, String serviceClassName) {
+        Map<String, Object> services = servicesLoaded.get(type);
+        if (services == null) {
+            return false;
+        }
+        return services.containsKey(serviceClassName);
+    }
+
+
+    private <S> S create(Class<S> serviceType, String className) {
+        Class<?> c = null;
+        ClassLoader classLoader = getClassLoader();
+        try {
+            c = Class.forName(className, false, classLoader);
+        } catch (ClassNotFoundException x) {
+            fail(serviceType,
+                    "Provider " + className + " not found");
+        }
+        if (!serviceType.isAssignableFrom(c)) {
+            fail(serviceType,
+                    "Provider " + className + " not a subtype");
+        }
+        try {
+            S p = serviceType.cast(c.newInstance());
+            return p;
+        } catch (Throwable x) {
+            fail(serviceType,
+                    "Provider " + className + " could not be instantiated",
+                    x);
+        }
+        throw new Error();          // This cannot happen
+    }
+
+    public <T> Collection<T> getServices(Class<T> serviceType) {
+        Map<String, Object> services = this.servicesLoaded.get(serviceType);
+        if (services != null) {
+            return (Collection<T>) services.values();
+        }
+        return Collections.emptySet();
+    }
+
+    public boolean isTypeLoaded(Class<?> serviceType) {
+        return this.servicesLoaded.containsKey(serviceType);
+    }
+
+    public Collection<URL> load(Class<?> serviceType) {
+        return load(serviceType, Collection.class.cast(Collections.emptySet()));
+    }
+
+    public Collection<URL> load(Class<?> serviceType, Collection<URL> configsLoaded) {
+        List<URL> result = new ArrayList<>();
+        try {
+            Enumeration<URL> resources = getClassLoader().getResources(PREFIX + serviceType.getName());
+            while (resources.hasMoreElements()) {
+                URL res = resources.nextElement();
+                if (!configsLoaded.contains(res)) {
+                    result.add(res);
+                }
+            }
+            return result;
+        } catch (Exception e) {
+            fail(serviceType, "Failed to load service config: " + PREFIX + serviceType.getName(), e);
+        }
+        return result;
+    }
+
+
+    // Parse a single line from the given configuration file, adding the name
+    // on the line to the names list.
+    //
+    private int parseLine(Class<?> serviceType, URL u, BufferedReader r, int lc,
+                          List<String> names)
+            throws IOException, ServiceConfigurationError {
+        String ln = r.readLine();
+        if (ln == null) {
+            return -1;
+        }
+        int ci = ln.indexOf('#');
+        if (ci >= 0) {
+            ln = ln.substring(0, ci);
+        }
+        ln = ln.trim();
+        int n = ln.length();
+        if (n != 0) {
+            if ((ln.indexOf(' ') >= 0) || (ln.indexOf('\t') >= 0)) {
+                fail(serviceType, u, lc, "Illegal configuration-file syntax");
+            }
+            int cp = ln.codePointAt(0);
+            if (!Character.isJavaIdentifierStart(cp)) {
+                fail(serviceType, u, lc, "Illegal provider-class name: " + ln);
+            }
+            for (int i = Character.charCount(cp); i < n; i += Character.charCount(cp)) {
+                cp = ln.codePointAt(i);
+                if (!Character.isJavaIdentifierPart(cp) && (cp != '.')) {
+                    fail(serviceType, u, lc, "Illegal provider-class name: " + ln);
+                }
+            }
+            Map<String, Object> services = this.servicesLoaded.get(serviceType);
+            if (services == null || !services.containsKey(ln) && !names.contains(ln)) {
+                names.add(ln);
+            }
+        }
+        return lc + 1;
+    }
+
+
+    // Parse the content of the given URL as a provider-configuration file.
+    //
+    // @param  service
+    //         The service type for which providers are being sought;
+    //         used to construct error detail strings
+    //
+    // @param  u
+    //         The URL naming the configuration file to be parsed
+    //
+    // @return A (possibly empty) iterator that will yield the provider-class
+    //         names in the given configuration file that are not yet members
+    //         of the returned set
+    //
+    // @throws ServiceConfigurationError
+    //         If an I/O error occurs while reading from the given URL, or
+    //         if a configuration-file format error is detected
+    //
+    private Collection<String> parse(Class<?> service, URL u)
+            throws ServiceConfigurationError {
+        InputStream in = null;
+        BufferedReader r = null;
+        ArrayList<String> names = new ArrayList<>();
+        try {
+            in = u.openStream();
+            r = new BufferedReader(new InputStreamReader(in, "utf-8"));
+            int lc = 1;
+            while ((lc = parseLine(service, u, r, lc, names)) >= 0) {
+                // go ahead
+            }
+        } catch (IOException x) {
+            fail(service, "Error reading configuration file", x);
+        } finally {
+            try {
+                if (r != null) {
+                    r.close();
+                }
+                if (in != null) {
+                    in.close();
+                }
+            } catch (IOException y) {
+                fail(service, "Error closing configuration file", y);
+            }
+        }
+        return names;
+    }
+
+
+    private static void fail(Class<?> service, String msg, Throwable cause)
+            throws ServiceConfigurationError {
+        LOG.log(Level.SEVERE, "Failed to load: " + service.getName() + ": " + msg, cause);
+    }
+
+    private static void fail(Class<?> service, String msg)
+            throws ServiceConfigurationError {
+        LOG.log(Level.SEVERE, "Failed to load: " + service.getName() + ": " + msg);
+    }
+
+    private static void fail(Class<?> service, URL u, int line, String msg)
+            throws ServiceConfigurationError {
+        fail(service, u + ":" + line + ": " + msg);
+    }
+
+    public <T> T getSingleton(Class<T> serviceType) {
+        return (T) this.singletons.get(serviceType);
+    }
+
+    <T> void setSingleton(Class<T> type, T instance) {
+        LOG.info("Caching singleton for " + type.getName() + " and classloader: " +
+                getClassLoader().toString() + ": " + instance);
+        this.singletons.put(type, instance);
+    }
+}

http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/blob/03a58b64/src/main/java/org/apache/tamaya/clsupport/internal/CLAwareConfigurationContext.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/tamaya/clsupport/internal/CLAwareConfigurationContext.java b/src/main/java/org/apache/tamaya/clsupport/internal/CLAwareConfigurationContext.java
deleted file mode 100644
index 8575393..0000000
--- a/src/main/java/org/apache/tamaya/clsupport/internal/CLAwareConfigurationContext.java
+++ /dev/null
@@ -1,106 +0,0 @@
-/*
- * 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.tamaya.clsupport.internal;
-
-import org.apache.tamaya.TypeLiteral;
-import org.apache.tamaya.clsupport.AbstractClassloaderAwareItemLoader;
-import org.apache.tamaya.clsupport.internal.ctx.DefaultConfigurationContext;
-import org.apache.tamaya.spi.ConfigurationContext;
-import org.apache.tamaya.spi.ConfigurationContextBuilder;
-import org.apache.tamaya.spi.PropertyConverter;
-import org.apache.tamaya.spi.PropertyFilter;
-import org.apache.tamaya.spi.PropertySource;
-import org.apache.tamaya.spi.PropertyValueCombinationPolicy;
-
-import javax.annotation.Priority;
-import java.util.List;
-import java.util.Map;
-import java.util.logging.Logger;
-
-/**
- * Default Implementation of a simple ConfigurationContext.
- */
-@Priority(100)
-public class CLAwareConfigurationContext implements ConfigurationContext {
-
-    /** The logger used. */
-    private final static Logger LOG = Logger.getLogger(CLAwareConfigurationContext.class.getName());
-
-    private ContextManager contextManager = new ContextManager();
-
-
-    @Override
-    public void addPropertySources(PropertySource... propertySourcesToAdd) {
-        contextManager.getItemNoParent(true).addPropertySources(propertySourcesToAdd);
-    }
-
-    @Override
-    public List<PropertySource> getPropertySources() {
-        return contextManager.getItemNoParent(true).getPropertySources();
-    }
-
-    @Override
-    public <T> void addPropertyConverter(TypeLiteral<T> typeToConvert, PropertyConverter<T> propertyConverter) {
-        contextManager.getItemNoParent(true).addPropertyConverter(typeToConvert, propertyConverter);
-    }
-
-    @Override
-    public Map<TypeLiteral<?>, List<PropertyConverter<?>>> getPropertyConverters() {
-        return contextManager.getItemNoParent(true).getPropertyConverters();
-    }
-
-    @Override
-    public <T> List<PropertyConverter<T>> getPropertyConverters(TypeLiteral<T> targetType) {
-        return contextManager.getItemNoParent(true).getPropertyConverters(targetType);
-    }
-
-    @Override
-    public List<PropertyFilter> getPropertyFilters() {
-        return contextManager.getItemNoParent(true).getPropertyFilters();
-    }
-
-    @Override
-    public PropertyValueCombinationPolicy getPropertyValueCombinationPolicy(){
-        return contextManager.getItemNoParent(true).getPropertyValueCombinationPolicy();
-    }
-
-    @Override
-    public ConfigurationContextBuilder toBuilder() {
-        return contextManager.getItemNoParent(true).toBuilder();
-    }
-
-
-    /**
-     * Subcomponent managing {@link ConfigurationContext} instances, one per classloader.
-     */
-    private static final class ContextManager extends AbstractClassloaderAwareItemLoader<ConfigurationContext>{
-
-        @Override
-        protected ConfigurationContext createItem(ClassLoader classLoader) {
-            // Simply create a complete configuration manager for every classloader. Maybe we will optimize this at a
-            // later stage in the project but as for now it is the most simple working solution.
-            return new DefaultConfigurationContext();
-        }
-
-        @Override
-        protected void updateItem(ConfigurationContext currentItemSet, ClassLoader classLoader) {
-            // ignore, currently not supported.
-        }
-    }
-}

http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/blob/03a58b64/src/main/java/org/apache/tamaya/clsupport/internal/CLAwareServiceContext.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/tamaya/clsupport/internal/CLAwareServiceContext.java b/src/main/java/org/apache/tamaya/clsupport/internal/CLAwareServiceContext.java
deleted file mode 100644
index 02caed0..0000000
--- a/src/main/java/org/apache/tamaya/clsupport/internal/CLAwareServiceContext.java
+++ /dev/null
@@ -1,247 +0,0 @@
-/*
- * 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.tamaya.clsupport.internal;
-
-import org.apache.tamaya.ConfigException;
-import org.apache.tamaya.clsupport.AbstractClassloaderAwareItemLoader;
-import org.apache.tamaya.spi.ServiceContext;
-
-import javax.annotation.Priority;
-import java.text.MessageFormat;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
-import java.util.logging.Level;
-import java.util.logging.Logger;
-
-
-/**
- * This class implements a {@link ServiceContext}, which basically provides a similar loading mechanism as used
- * by the {@link java.util.ServiceLoader}. Whereas the {@link java.util.ServiceLoader} only loads configurations
- * and instances from one classloader, this loader manages configs found and the related instances for each
- * classloader along the classloader hierarchies individually. It ensures instances are loaded on the classloader
- * level, where they first are visible. Additionally it ensures the same configuration resource (and its
- * declared services) are loaded multiple times, when going up the classloader hierarchy.<p/>
- * Finally classloaders are not stored by reference by this class, to ensure they still can be garbage collected.
- * Refer also the inherited parent class for further details.<p/>
- * This class uses an ordinal of {@code 10}, so it overrides any default {@link ServiceContext} implementations
- * provided with the Tamaya core modules.
- */
-@Priority(10)
-public class CLAwareServiceContext extends AbstractClassloaderAwareItemLoader<ServiceContainer>
-        implements ServiceContext{
-
-    private static final Logger LOG = Logger.getLogger(CLAwareServiceContext.class.getName());
-
-    /**
-     * Default location for service loader files.
-     */
-    private static final String PREFIX = "META-INF/services/";
-
-    /**
-     * Constructor, using the current default classloader as defined by
-     * {@link AbstractClassloaderAwareItemLoader#getDefaultClassLoader()}.
-     */
-    public CLAwareServiceContext(){
-        super();
-    }
-
-    /**
-     * Constructor, using the given classloader.
-     * @param classLoader the target classloader for initializing of services, not null.
-     */
-    public CLAwareServiceContext(ClassLoader classLoader) {
-        super(classLoader);
-    }
-
-
-    /**
-     * Implementation that creates a {@link ServiceContainer}, which manages all configs and instances loaded
-     * for a given classloader.
-     * @param classLoader the classloader, not null.
-     * @return a new empty, {@link ServiceContainer} instance.
-     */
-    @Override
-    protected ServiceContainer createItem(ClassLoader classLoader) {
-        if(LOG.isLoggable(Level.INFO)) {
-            LOG.info("Loading services for classloader: " + classLoader);
-        }
-        return new ServiceContainer(classLoader);
-    }
-
-    @Override
-    protected void updateItem(ServiceContainer currentContainer, ClassLoader classLoader) {
-        // nothing to be done here, since we dont have a specific target type.
-    }
-
-    @Override
-    public int ordinal() {
-        return 10;
-    }
-
-    /**
-     * This method tries to evaluate the current singleton from the {@link ServiceContainer} attached to the
-     * current classloader. If not found the singleton instance is evaluated based on the priorities
-     * assigned for all known providers. The resulting instance is then cached and always returned as
-     * singleton instance fomr this loader, when the same current classloader instance is active.
-     * @param serviceType the service type.
-     * @param <T> the type
-     * @return the item found, or null.
-     */
-    @Override
-    public <T> T getService(Class<T> serviceType) {
-        return getService(serviceType, getDefaultClassLoader());
-    }
-
-    /**
-     * Evaluates the current singleton instance using the given classloader context.
-     * @param serviceType the service type.
-     * @param classLoader the classloader, not null.
-     * @param <T> the type
-     * @return the item found, or null.
-     */
-    public <T> T getService(Class<T> serviceType, ClassLoader classLoader) {
-        if(LOG.isLoggable(Level.INFO)) {
-            LOG.info("Evaluating services for classloader: " + classLoader);
-        }
-        ServiceContainer container = getItemNoParent(classLoader, true);
-        T singleton = container.getSingleton(serviceType);
-        if(singleton!=null){
-            if(LOG.isLoggable(Level.FINEST)) {
-                LOG.finest("Evaluated singleton of type " + serviceType.getName() + " to " + singleton);
-            }
-            return singleton;
-        }
-        Collection<? extends T> services = getServices(serviceType, classLoader);
-        if (services.isEmpty()) {
-            singleton = null;
-        } else {
-            singleton = getServiceWithHighestPriority(services, serviceType);
-        }
-        if(singleton!=null) {
-            container.setSingleton(serviceType, singleton);
-        }
-        if(LOG.isLoggable(Level.FINEST)) {
-            LOG.finest("Evaluated singleton of type " + serviceType.getName() + " to " + singleton);
-        }
-        return singleton;
-    }
-
-    /**
-     * Gets the services visible.
-     * @param serviceType
-     *            the service type.
-     * @param <T> the type param
-     * @return the services visible for the current classloader.
-     */
-    @Override
-    public <T> List<T> getServices(Class<T> serviceType) {
-        return getServices(serviceType, AbstractClassloaderAwareItemLoader.getDefaultClassLoader());
-    }
-
-    /**
-     * Gets the services visible.
-     * @param serviceType the service type.
-     * @param classLoader the classloader
-     * @param <T> the type param
-     * @return the services visible for the current classloader.
-     */
-    public <T> List<T> getServices(Class<T> serviceType, ClassLoader classLoader) {
-        List<T> services = new ArrayList<>();
-        ClassLoader cl = classLoader;
-        List<ServiceContainer> containers = new ArrayList<>();
-        while(cl!=null) {
-            ServiceContainer container = getItemNoParent(cl, true);
-            containers.add(container);
-            cl = cl.getParent();
-        }
-        List<ServiceContainer> prevContainers = new ArrayList<>();
-        Collections.reverse(containers);
-        for(ServiceContainer container: containers) {
-            if (!container.isTypeLoaded(serviceType)) {
-                container.loadServices(serviceType, prevContainers);
-            }
-            services.addAll(container.getServices(serviceType));
-            prevContainers.add(container);
-        }
-        if(LOG.isLoggable(Level.FINEST)) {
-            LOG.finest("Evaluated services of type " + serviceType.getName() + " to " + services);
-        }
-        return services;
-    }
-
-    /**
-     * @param services to scan
-     * @param <T>      type of the service
-     *
-     * @return the service with the highest {@link javax.annotation.Priority#value()}
-     *
-     * @throws ConfigException if there are multiple service implementations with the maximum priority
-     */
-    private <T> T getServiceWithHighestPriority(Collection<? extends T> services, Class<T> serviceType) {
-
-        // we do not need the priority stuff if the list contains only one element
-        if (services.size() == 1) {
-            return services.iterator().next();
-        }
-
-        Integer highestPriority = null;
-        int highestPriorityServiceCount = 0;
-        T highestService = null;
-
-        for (T service : services) {
-            int prio = getPriority(service);
-            if (highestPriority == null || highestPriority < prio) {
-                highestService = service;
-                highestPriorityServiceCount = 1;
-                highestPriority = prio;
-            } else if (highestPriority == prio) {
-                highestPriorityServiceCount++;
-            }
-        }
-        if (highestPriorityServiceCount > 1) {
-            throw new ConfigException(MessageFormat.format("Found {0} implementations for Service {1} with Priority {2}: {3}",
-                    highestPriorityServiceCount,
-                    serviceType.getName(),
-                    highestPriority,
-                    services));
-        }
-        return highestService;
-    }
-
-    /**
-     * Checks the given instance for a @Priority annotation. If present the annotation's value s evaluated. If no such
-     * annotation is present, a default priority is returned (1);
-     * @param o the instance, not null.
-     * @return a priority, by default 1.
-     */
-    public static int getPriority(Object o){
-        int prio = 0;
-        Priority priority = o.getClass().getAnnotation(Priority.class);
-        if (priority != null) {
-            prio = priority.value();
-        }
-        if(LOG.isLoggable(Level.FINEST)) {
-            LOG.finest("Evaluated priority for " + o.getClass().getName() + " to " + prio);
-        }
-        return prio;
-    }
-
-}

http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/blob/03a58b64/src/main/java/org/apache/tamaya/clsupport/internal/ServiceContainer.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/tamaya/clsupport/internal/ServiceContainer.java b/src/main/java/org/apache/tamaya/clsupport/internal/ServiceContainer.java
deleted file mode 100644
index 713b292..0000000
--- a/src/main/java/org/apache/tamaya/clsupport/internal/ServiceContainer.java
+++ /dev/null
@@ -1,311 +0,0 @@
-/*
- * 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.tamaya.clsupport.internal;
-
-import java.io.BufferedReader;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.InputStreamReader;
-import java.lang.ref.WeakReference;
-import java.net.URL;
-import java.security.AccessControlContext;
-import java.security.AccessController;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.Enumeration;
-import java.util.LinkedHashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.ServiceConfigurationError;
-import java.util.concurrent.ConcurrentHashMap;
-import java.util.logging.Level;
-import java.util.logging.Logger;
-
-/**
- * Created by Anatole on 08.09.2015.
- */
-class ServiceContainer {
-
-    private static final Logger LOG = Logger.getLogger(ServiceContainer.class.getName());
-
-    private static final String PREFIX = "META-INF/services/";
-
-    // The access control context taken when the ServiceLoader is created
-    private final AccessControlContext acc;
-
-    private WeakReference<ClassLoader> classLoaderRef;
-
-    /**
-     * List current services loaded using this classloader, per class.
-     */
-    private final Map<Class<?>, Map<String, Object>> servicesLoaded = new ConcurrentHashMap<>();
-    /**
-     * The cached singletons for the given classloader.
-     */
-    private final Map<Class, Object> singletons = new ConcurrentHashMap<>();
-
-    /**
-     * List current services loaded using this classloader, per class.
-     */
-    private final Map<Class, List<URL>> configsLoaded = new ConcurrentHashMap<>();
-
-    ServiceContainer(ClassLoader classLoader) {
-        acc = (System.getSecurityManager() != null) ? AccessController.getContext() : null;
-        this.classLoaderRef = new WeakReference<>(classLoader);
-    }
-
-    public ClassLoader getClassLoader() {
-        ClassLoader cl = classLoaderRef.get();
-        if (cl == null) {
-            throw new IllegalStateException("Classloader reference removed, not active anynire.");
-        }
-        return cl;
-    }
-
-
-    public <T> void loadServices(Class<?> type,
-                                 Collection<ServiceContainer> preceedingContainers) {
-        Map<String, Object> services = (Map<String, Object>) this.servicesLoaded.get(type);
-        if (services == null) {
-            services = new LinkedHashMap<>();
-            this.servicesLoaded.put(type, services);
-        }
-        loop:
-        for (URL config : getConfigs(type)) {
-            for (ServiceContainer cont : preceedingContainers) {
-                if (cont.getConfigs(type).contains(config)) {
-                    LOG.finer("Ignoring already loaded config: " + config);
-                    continue loop;
-                }
-            }
-            Collection<String> serviceNames = parse(type, config);
-            for (String s : serviceNames) {
-                for (ServiceContainer cont : preceedingContainers) {
-                    if (cont.containsService(type, s)) {
-                        LOG.finest("Ignoring duplicate service: " + s);
-                        continue;
-                    }
-                }
-                LOG.info("Loading component: " + s);
-                services.put(s, create(type, s));
-            }
-        }
-    }
-
-    private Collection<URL> getConfigs(Class<?> type) {
-        List<URL> result = this.configsLoaded.get(type);
-        if (result == null) {
-            ClassLoader cl = this.classLoaderRef.get();
-            if (cl == null) {
-                throw new IllegalStateException("CLassLoader dereferenced already.");
-            }
-            result = new ArrayList<>();
-            try {
-                Enumeration<URL> resources = cl.getResources(PREFIX + type.getName());
-                while (resources.hasMoreElements()) {
-                    result.add(resources.nextElement());
-                }
-            } catch (Exception e) {
-                LOG.log(Level.WARNING, "Failed to read service config for " + type.getName() + " from " + cl, e);
-            }
-            this.configsLoaded.put(type, result);
-            LOG.log(Level.FINE, "Found service config for " + type.getName() + ": " + result);
-        }
-        return result;
-    }
-
-    private boolean containsService(Class<?> type, String serviceClassName) {
-        Map<String, Object> services = servicesLoaded.get(type);
-        if (services == null) {
-            return false;
-        }
-        return services.containsKey(serviceClassName);
-    }
-
-
-    private <S> S create(Class<S> serviceType, String className) {
-        Class<?> c = null;
-        ClassLoader classLoader = getClassLoader();
-        try {
-            c = Class.forName(className, false, classLoader);
-        } catch (ClassNotFoundException x) {
-            fail(serviceType,
-                    "Provider " + className + " not found");
-        }
-        if (!serviceType.isAssignableFrom(c)) {
-            fail(serviceType,
-                    "Provider " + className + " not a subtype");
-        }
-        try {
-            S p = serviceType.cast(c.newInstance());
-            return p;
-        } catch (Throwable x) {
-            fail(serviceType,
-                    "Provider " + className + " could not be instantiated",
-                    x);
-        }
-        throw new Error();          // This cannot happen
-    }
-
-    public <T> Collection<T> getServices(Class<T> serviceType) {
-        Map<String, Object> services = this.servicesLoaded.get(serviceType);
-        if (services != null) {
-            return (Collection<T>) services.values();
-        }
-        return Collections.emptySet();
-    }
-
-    public boolean isTypeLoaded(Class<?> serviceType) {
-        return this.servicesLoaded.containsKey(serviceType);
-    }
-
-    public Collection<URL> load(Class<?> serviceType) {
-        return load(serviceType, Collection.class.cast(Collections.emptySet()));
-    }
-
-    public Collection<URL> load(Class<?> serviceType, Collection<URL> configsLoaded) {
-        List<URL> result = new ArrayList<>();
-        try {
-            Enumeration<URL> resources = getClassLoader().getResources(PREFIX + serviceType.getName());
-            while (resources.hasMoreElements()) {
-                URL res = resources.nextElement();
-                if (!configsLoaded.contains(res)) {
-                    result.add(res);
-                }
-            }
-            return result;
-        } catch (Exception e) {
-            fail(serviceType, "Failed to load service config: " + PREFIX + serviceType.getName(), e);
-        }
-        return result;
-    }
-
-
-    // Parse a single line from the given configuration file, adding the name
-    // on the line to the names list.
-    //
-    private int parseLine(Class<?> serviceType, URL u, BufferedReader r, int lc,
-                          List<String> names)
-            throws IOException, ServiceConfigurationError {
-        String ln = r.readLine();
-        if (ln == null) {
-            return -1;
-        }
-        int ci = ln.indexOf('#');
-        if (ci >= 0) {
-            ln = ln.substring(0, ci);
-        }
-        ln = ln.trim();
-        int n = ln.length();
-        if (n != 0) {
-            if ((ln.indexOf(' ') >= 0) || (ln.indexOf('\t') >= 0)) {
-                fail(serviceType, u, lc, "Illegal configuration-file syntax");
-            }
-            int cp = ln.codePointAt(0);
-            if (!Character.isJavaIdentifierStart(cp)) {
-                fail(serviceType, u, lc, "Illegal provider-class name: " + ln);
-            }
-            for (int i = Character.charCount(cp); i < n; i += Character.charCount(cp)) {
-                cp = ln.codePointAt(i);
-                if (!Character.isJavaIdentifierPart(cp) && (cp != '.')) {
-                    fail(serviceType, u, lc, "Illegal provider-class name: " + ln);
-                }
-            }
-            Map<String, Object> services = this.servicesLoaded.get(serviceType);
-            if (services == null || !services.containsKey(ln) && !names.contains(ln)) {
-                names.add(ln);
-            }
-        }
-        return lc + 1;
-    }
-
-
-    // Parse the content of the given URL as a provider-configuration file.
-    //
-    // @param  service
-    //         The service type for which providers are being sought;
-    //         used to construct error detail strings
-    //
-    // @param  u
-    //         The URL naming the configuration file to be parsed
-    //
-    // @return A (possibly empty) iterator that will yield the provider-class
-    //         names in the given configuration file that are not yet members
-    //         of the returned set
-    //
-    // @throws ServiceConfigurationError
-    //         If an I/O error occurs while reading from the given URL, or
-    //         if a configuration-file format error is detected
-    //
-    private Collection<String> parse(Class<?> service, URL u)
-            throws ServiceConfigurationError {
-        InputStream in = null;
-        BufferedReader r = null;
-        ArrayList<String> names = new ArrayList<>();
-        try {
-            in = u.openStream();
-            r = new BufferedReader(new InputStreamReader(in, "utf-8"));
-            int lc = 1;
-            while ((lc = parseLine(service, u, r, lc, names)) >= 0) {
-                // go ahead
-            }
-        } catch (IOException x) {
-            fail(service, "Error reading configuration file", x);
-        } finally {
-            try {
-                if (r != null) {
-                    r.close();
-                }
-                if (in != null) {
-                    in.close();
-                }
-            } catch (IOException y) {
-                fail(service, "Error closing configuration file", y);
-            }
-        }
-        return names;
-    }
-
-
-    private static void fail(Class<?> service, String msg, Throwable cause)
-            throws ServiceConfigurationError {
-        LOG.log(Level.SEVERE, "Failed to load: " + service.getName() + ": " + msg, cause);
-    }
-
-    private static void fail(Class<?> service, String msg)
-            throws ServiceConfigurationError {
-        LOG.log(Level.SEVERE, "Failed to load: " + service.getName() + ": " + msg);
-    }
-
-    private static void fail(Class<?> service, URL u, int line, String msg)
-            throws ServiceConfigurationError {
-        fail(service, u + ":" + line + ": " + msg);
-    }
-
-    public <T> T getSingleton(Class<T> serviceType) {
-        return (T) this.singletons.get(serviceType);
-    }
-
-    <T> void setSingleton(Class<T> type, T instance) {
-        LOG.info("Caching singleton for " + type.getName() + " and classloader: " +
-                getClassLoader().toString() + ": " + instance);
-        this.singletons.put(type, instance);
-    }
-}

http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/blob/03a58b64/src/main/java/org/apache/tamaya/clsupport/internal/package-info.java
----------------------------------------------------------------------
diff --git a/src/main/java/org/apache/tamaya/clsupport/internal/package-info.java b/src/main/java/org/apache/tamaya/clsupport/internal/package-info.java
deleted file mode 100644
index 3949b74..0000000
--- a/src/main/java/org/apache/tamaya/clsupport/internal/package-info.java
+++ /dev/null
@@ -1,22 +0,0 @@
-/*
- * 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.
- */
-/**
- * Contains the provided implementation classes for the classloader support module.
- */
-package org.apache.tamaya.clsupport.internal;
\ No newline at end of file

http://git-wip-us.apache.org/repos/asf/incubator-tamaya-sandbox/blob/03a58b64/src/main/resources/META-INF/services/org.apache.tamaya.spi.ServiceContext
----------------------------------------------------------------------
diff --git a/src/main/resources/META-INF/services/org.apache.tamaya.spi.ServiceContext b/src/main/resources/META-INF/services/org.apache.tamaya.spi.ServiceContext
index c3b6acd..7016afb 100644
--- a/src/main/resources/META-INF/services/org.apache.tamaya.spi.ServiceContext
+++ b/src/main/resources/META-INF/services/org.apache.tamaya.spi.ServiceContext
@@ -16,4 +16,4 @@
 # specific language governing permissions and limitations
 # under the License.
 #
-org.apache.tamaya.clsupport.internal.CLAwareServiceContext
+org.apache.tamaya.clsupport.CLAwareServiceContext