jndi/jndi-core/src/main/java/org/apache/aries/jndi/ObjectFactoryHelper.java - aries - Git at Google

 /*
  * 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.aries.jndi;

 import org.apache.aries.jndi.startup.Activator;
 import org.osgi.framework.BundleContext;
 import org.osgi.framework.ServiceReference;

 import javax.naming.*;
 import javax.naming.directory.Attributes;
 import javax.naming.spi.DirObjectFactory;
 import javax.naming.spi.ObjectFactory;
 import javax.naming.spi.ObjectFactoryBuilder;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
 import java.util.Enumeration;
 import java.util.Hashtable;
 import java.util.logging.Level;
 import java.util.logging.Logger;

 public class ObjectFactoryHelper implements ObjectFactory {

     private static final Logger logger = Logger.getLogger(ObjectFactoryHelper.class.getName());

     protected BundleContext defaultContext;
     protected BundleContext callerContext;

     public ObjectFactoryHelper(BundleContext defaultContext, BundleContext callerContext) {
         this.defaultContext = defaultContext;
         this.callerContext = callerContext;
     }

     public Object getObjectInstance(Object obj,
                                     Name name,
                                     Context nameCtx,
                                     Hashtable<?, ?> environment) throws Exception {

         return getObjectInstance(obj, name, nameCtx, environment, null);
     }

     public Object getObjectInstance(Object obj,
                                     Name name,
                                     Context nameCtx,
                                     Hashtable<?, ?> environment,
                                     Attributes attrs) throws Exception {
         return Utils.doPrivilegedE(() -> doGetObjectInstance(obj, name, nameCtx, environment, attrs));
     }

     private Object doGetObjectInstance(Object obj,
                                     Name name,
                                     Context nameCtx,
                                     Hashtable<?, ?> environment,
                                     Attributes attrs) throws Exception {
         // Step 1
         if (obj instanceof Referenceable) {
             obj = ((Referenceable) obj).getReference();
         }

         Object result = obj;

         // Step 2
         if (obj instanceof Reference) {
             Reference ref = (Reference) obj;
             String className = ref.getFactoryClassName();

             if (className != null) {
                 // Step 3
                 result = getObjectInstanceUsingClassName(obj, className, obj, name, nameCtx, environment, attrs);
             } else {
                 // Step 4 - look, assuming url string ref addrs, for a url context object factory.
                 result = getObjectInstanceUsingRefAddress(ref.getAll(), obj, name, nameCtx, environment, attrs);
             }
         }

         // Step 4
         if (result == null || result == obj) {
             result = getObjectInstanceUsingObjectFactoryBuilders(obj, name, nameCtx, environment, attrs);
         }

         // Step 5
         if (result == null || result == obj) {
             if (!(obj instanceof Reference) || ((Reference) obj).getFactoryClassName() == null) {
                 result = getObjectInstanceUsingObjectFactories(obj, name, nameCtx, environment, attrs);
             }
         }

         // Extra, non-standard, bonus step. If javax.naming.OBJECT_FACTORIES is set as
         // a property in the environment, use its value to construct additional object factories.
         // Added under Aries-822, with reference
         // to https://www.osgi.org/bugzilla/show_bug.cgi?id=138
         if (result == null || result == obj) {
             result = getObjectInstanceViaContextDotObjectFactories(obj, name, nameCtx, environment, attrs);
         }

         return (result == null) ? obj : result;
     }

     private Object getObjectInstanceUsingObjectFactories(Object obj,
                                                          Name name,
                                                          Context nameCtx,
                                                          Hashtable<?, ?> environment,
                                                          Attributes attrs) throws Exception {
         for (ServiceReference<ObjectFactory> ref : Activator.getReferences(callerContext, ObjectFactory.class)) {
             if (canCallObjectFactory(obj, ref)) {
                 ObjectFactory factory = Activator.getService(callerContext, ref);
                 if (factory != null) {
                     Object result = getObjectFromFactory(obj, name, nameCtx, environment, attrs, factory);
                     // if the result comes back and is not null and not the reference
                     // object then we should return the result, so break out of the
                     // loop we are in.
                     if (result != null && result != obj) {
                         return result;
                     }
                 }
             }
         }
         return obj;
     }

     private boolean canCallObjectFactory(Object obj, ServiceReference ref) {
         if (obj instanceof Reference) return true;
         Object prop = ref.getProperty("aries.object.factory.requires.reference");
         return (prop == null) || !(prop instanceof Boolean) || !(Boolean) prop;
     }

     private Object getObjectInstanceUsingClassName(Object reference,
                                                    String className,
                                                    Object obj,
                                                    Name name,
                                                    Context nameCtx,
                                                    Hashtable<?, ?> environment,
                                                    Attributes attrs)
             throws Exception {

         Object result = null;

         ObjectFactory factory = ObjectFactoryHelper.findObjectFactoryByClassName(defaultContext, className);
         if (factory != null) {
             result = getObjectFromFactory(reference, name, nameCtx, environment, attrs, factory);
         }

         return (result == null) ? obj : result;
     }

     private Object getObjectInstanceUsingObjectFactoryBuilders(Object obj,
                                                                Name name,
                                                                Context nameCtx,
                                                                Hashtable<?, ?> environment,
                                                                Attributes attrs)
             throws Exception {
         ObjectFactory factory = null;
         for (ObjectFactoryBuilder ofb : Activator.getServices(callerContext, ObjectFactoryBuilder.class)) {
             try {
                 factory = ofb.createObjectFactory(obj, environment);
             } catch (NamingException e) {
                 // TODO: log it
             }
             if (factory != null) {
                 break;
             }
         }

         Object result = null;

         if (factory != null) {
             result = getObjectFromFactory(obj, name, nameCtx, environment, attrs, factory);
         }

         return (result == null) ? obj : result;
     }

     /*
      * Attempt to obtain an Object instance via the java.naming.factory.object property
      */
     private Object getObjectInstanceViaContextDotObjectFactories(Object obj,
                                                                  Name name,
                                                                  Context nameCtx,
                                                                  Hashtable<?, ?> environment,
                                                                  Attributes attrs) throws Exception {
         Object result = null;
         String factories = (String) environment.get(Context.OBJECT_FACTORIES);
         if (factories != null && factories.length() > 0) {
             String[] candidates = factories.split(":");
             ClassLoader cl = Utils.doPrivileged(Thread.currentThread()::getContextClassLoader);
             for (String cand : candidates) {
                 ObjectFactory factory;
                 try {
                     @SuppressWarnings("unchecked")
                     Class<ObjectFactory> clz = (Class<ObjectFactory>) cl.loadClass(cand);
                     factory = clz.newInstance();
                 } catch (Exception e) {
                     if (logger.isLoggable(Level.FINE)) logger.log(Level.FINE, "Exception instantiating factory: " + e);
                     continue;
                 }
                 if (logger.isLoggable(Level.FINE)) logger.log(Level.FINE, "cand=" + cand + " factory=" + factory);
                 if (factory != null) {
                     result = getObjectFromFactory(obj, name, nameCtx, environment, attrs, factory);
                 }
                 if (result != null && result != obj) break;
             }
         }
         if (logger.isLoggable(Level.FINE)) logger.log(Level.FINE, "result = " + result);
         return (result == null) ? obj : result;
     }

     private Object getObjectInstanceUsingRefAddress(Enumeration<RefAddr> addresses,
                                                     Object obj,
                                                     Name name,
                                                     Context nameCtx,
                                                     Hashtable<?, ?> environment,
                                                     Attributes attrs)
             throws Exception {
         while (addresses.hasMoreElements()) {
             RefAddr address = addresses.nextElement();
             if (address instanceof StringRefAddr && "URL".equals(address.getType())) {
                 String urlScheme = getUrlScheme((String) address.getContent());

                 ServicePair<ObjectFactory> factoryService = ContextHelper.getURLObjectFactory(callerContext, urlScheme, environment);

                 if (factoryService != null) {
                     ObjectFactory factory = factoryService.get();

                     String value = (String) address.getContent();
                     Object result = getObjectFromFactory(value, name, nameCtx, environment, attrs, factory);

                     // if the result comes back and is not null and not the reference
                     // object then we should return the result, so break out of the
                     // loop we are in.
                     if (result != null && result != obj) {
                         return result;
                     }
                 }
             }
         }

         return obj;
     }

     private Object getObjectFromFactory(Object obj, Name name, Context nameCtx, Hashtable<?, ?> environment, Attributes attrs, ObjectFactory factory) throws Exception {
         Object result;
         if (factory instanceof DirObjectFactory) {
             result = ((DirObjectFactory) factory).getObjectInstance(obj, name, nameCtx, environment, attrs);
         } else {
             result = factory.getObjectInstance(obj, name, nameCtx, environment);
         }
         return result;
     }

     private static String getUrlScheme(String name) {
         String scheme = name;
         int index = name.indexOf(':');
         if (index != -1) {
             scheme = name.substring(0, index);
         }
         return scheme;
     }

     private static ObjectFactory findObjectFactoryByClassName(final BundleContext ctx, final String className) {
         return Utils.doPrivileged(() -> {
             ServiceReference<?> ref = ctx.getServiceReference(className);
             if (ref != null) {
                 return (ObjectFactory) Activator.getService(ctx, ref);
             }
             return null;
         });
     }

 }
	/*
	* 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.aries.jndi;

	import org.apache.aries.jndi.startup.Activator;
	import org.osgi.framework.BundleContext;
	import org.osgi.framework.ServiceReference;

	import javax.naming.*;
	import javax.naming.directory.Attributes;
	import javax.naming.spi.DirObjectFactory;
	import javax.naming.spi.ObjectFactory;
	import javax.naming.spi.ObjectFactoryBuilder;
	import java.security.AccessController;
	import java.security.PrivilegedAction;
	import java.util.Enumeration;
	import java.util.Hashtable;
	import java.util.logging.Level;
	import java.util.logging.Logger;

	public class ObjectFactoryHelper implements ObjectFactory {

	private static final Logger logger = Logger.getLogger(ObjectFactoryHelper.class.getName());

	protected BundleContext defaultContext;
	protected BundleContext callerContext;

	public ObjectFactoryHelper(BundleContext defaultContext, BundleContext callerContext) {
	this.defaultContext = defaultContext;
	this.callerContext = callerContext;
	}

	public Object getObjectInstance(Object obj,
	Name name,
	Context nameCtx,
	Hashtable<?, ?> environment) throws Exception {

	return getObjectInstance(obj, name, nameCtx, environment, null);
	}

	public Object getObjectInstance(Object obj,
	Name name,
	Context nameCtx,
	Hashtable<?, ?> environment,
	Attributes attrs) throws Exception {
	return Utils.doPrivilegedE(() -> doGetObjectInstance(obj, name, nameCtx, environment, attrs));
	}

	private Object doGetObjectInstance(Object obj,
	Name name,
	Context nameCtx,
	Hashtable<?, ?> environment,
	Attributes attrs) throws Exception {
	// Step 1
	if (obj instanceof Referenceable) {
	obj = ((Referenceable) obj).getReference();
	}

	Object result = obj;

	// Step 2
	if (obj instanceof Reference) {
	Reference ref = (Reference) obj;
	String className = ref.getFactoryClassName();

	if (className != null) {
	// Step 3
	result = getObjectInstanceUsingClassName(obj, className, obj, name, nameCtx, environment, attrs);
	} else {
	// Step 4 - look, assuming url string ref addrs, for a url context object factory.
	result = getObjectInstanceUsingRefAddress(ref.getAll(), obj, name, nameCtx, environment, attrs);
	}
	}

	// Step 4
	if (result == null \|\| result == obj) {
	result = getObjectInstanceUsingObjectFactoryBuilders(obj, name, nameCtx, environment, attrs);
	}

	// Step 5
	if (result == null \|\| result == obj) {
	if (!(obj instanceof Reference) \|\| ((Reference) obj).getFactoryClassName() == null) {
	result = getObjectInstanceUsingObjectFactories(obj, name, nameCtx, environment, attrs);
	}
	}

	// Extra, non-standard, bonus step. If javax.naming.OBJECT_FACTORIES is set as
	// a property in the environment, use its value to construct additional object factories.
	// Added under Aries-822, with reference
	// to https://www.osgi.org/bugzilla/show_bug.cgi?id=138
	if (result == null \|\| result == obj) {
	result = getObjectInstanceViaContextDotObjectFactories(obj, name, nameCtx, environment, attrs);
	}

	return (result == null) ? obj : result;
	}

	private Object getObjectInstanceUsingObjectFactories(Object obj,
	Name name,
	Context nameCtx,
	Hashtable<?, ?> environment,
	Attributes attrs) throws Exception {
	for (ServiceReference<ObjectFactory> ref : Activator.getReferences(callerContext, ObjectFactory.class)) {
	if (canCallObjectFactory(obj, ref)) {
	ObjectFactory factory = Activator.getService(callerContext, ref);
	if (factory != null) {
	Object result = getObjectFromFactory(obj, name, nameCtx, environment, attrs, factory);
	// if the result comes back and is not null and not the reference
	// object then we should return the result, so break out of the
	// loop we are in.
	if (result != null && result != obj) {
	return result;
	}
	}
	}
	}
	return obj;
	}

	private boolean canCallObjectFactory(Object obj, ServiceReference ref) {
	if (obj instanceof Reference) return true;
	Object prop = ref.getProperty("aries.object.factory.requires.reference");
	return (prop == null) \|\| !(prop instanceof Boolean) \|\| !(Boolean) prop;
	}

	private Object getObjectInstanceUsingClassName(Object reference,
	String className,
	Object obj,
	Name name,
	Context nameCtx,
	Hashtable<?, ?> environment,
	Attributes attrs)
	throws Exception {

	Object result = null;

	ObjectFactory factory = ObjectFactoryHelper.findObjectFactoryByClassName(defaultContext, className);
	if (factory != null) {
	result = getObjectFromFactory(reference, name, nameCtx, environment, attrs, factory);
	}

	return (result == null) ? obj : result;
	}

	private Object getObjectInstanceUsingObjectFactoryBuilders(Object obj,
	Name name,
	Context nameCtx,
	Hashtable<?, ?> environment,
	Attributes attrs)
	throws Exception {
	ObjectFactory factory = null;
	for (ObjectFactoryBuilder ofb : Activator.getServices(callerContext, ObjectFactoryBuilder.class)) {
	try {
	factory = ofb.createObjectFactory(obj, environment);
	} catch (NamingException e) {
	// TODO: log it
	}
	if (factory != null) {
	break;
	}
	}

	Object result = null;

	if (factory != null) {
	result = getObjectFromFactory(obj, name, nameCtx, environment, attrs, factory);
	}

	return (result == null) ? obj : result;
	}

	/*
	* Attempt to obtain an Object instance via the java.naming.factory.object property
	*/
	private Object getObjectInstanceViaContextDotObjectFactories(Object obj,
	Name name,
	Context nameCtx,
	Hashtable<?, ?> environment,
	Attributes attrs) throws Exception {
	Object result = null;
	String factories = (String) environment.get(Context.OBJECT_FACTORIES);
	if (factories != null && factories.length() > 0) {
	String[] candidates = factories.split(":");
	ClassLoader cl = Utils.doPrivileged(Thread.currentThread()::getContextClassLoader);
	for (String cand : candidates) {
	ObjectFactory factory;
	try {
	@SuppressWarnings("unchecked")
	Class<ObjectFactory> clz = (Class<ObjectFactory>) cl.loadClass(cand);
	factory = clz.newInstance();
	} catch (Exception e) {
	if (logger.isLoggable(Level.FINE)) logger.log(Level.FINE, "Exception instantiating factory: " + e);
	continue;
	}
	if (logger.isLoggable(Level.FINE)) logger.log(Level.FINE, "cand=" + cand + " factory=" + factory);
	if (factory != null) {
	result = getObjectFromFactory(obj, name, nameCtx, environment, attrs, factory);
	}
	if (result != null && result != obj) break;
	}
	}
	if (logger.isLoggable(Level.FINE)) logger.log(Level.FINE, "result = " + result);
	return (result == null) ? obj : result;
	}

	private Object getObjectInstanceUsingRefAddress(Enumeration<RefAddr> addresses,
	Object obj,
	Name name,
	Context nameCtx,
	Hashtable<?, ?> environment,
	Attributes attrs)
	throws Exception {
	while (addresses.hasMoreElements()) {
	RefAddr address = addresses.nextElement();
	if (address instanceof StringRefAddr && "URL".equals(address.getType())) {
	String urlScheme = getUrlScheme((String) address.getContent());

	ServicePair<ObjectFactory> factoryService = ContextHelper.getURLObjectFactory(callerContext, urlScheme, environment);

	if (factoryService != null) {
	ObjectFactory factory = factoryService.get();

	String value = (String) address.getContent();
	Object result = getObjectFromFactory(value, name, nameCtx, environment, attrs, factory);

	// if the result comes back and is not null and not the reference
	// object then we should return the result, so break out of the
	// loop we are in.
	if (result != null && result != obj) {
	return result;
	}
	}
	}
	}

	return obj;
	}

	private Object getObjectFromFactory(Object obj, Name name, Context nameCtx, Hashtable<?, ?> environment, Attributes attrs, ObjectFactory factory) throws Exception {
	Object result;
	if (factory instanceof DirObjectFactory) {
	result = ((DirObjectFactory) factory).getObjectInstance(obj, name, nameCtx, environment, attrs);
	} else {
	result = factory.getObjectInstance(obj, name, nameCtx, environment);
	}
	return result;
	}

	private static String getUrlScheme(String name) {
	String scheme = name;
	int index = name.indexOf(':');
	if (index != -1) {
	scheme = name.substring(0, index);
	}
	return scheme;
	}

	private static ObjectFactory findObjectFactoryByClassName(final BundleContext ctx, final String className) {
	return Utils.doPrivileged(() -> {
	ServiceReference<?> ref = ctx.getServiceReference(className);
	if (ref != null) {
	return (ObjectFactory) Activator.getService(ctx, ref);
	}
	return null;
	});
	}

	}