modules/extensibility-osgi/src/main/java/org/apache/tuscany/sca/extensibility/osgi/OSGiServiceDiscoverer.java - tuscany-sca-1.x - 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.tuscany.sca.extensibility.osgi;

 import java.io.BufferedReader;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.net.URL;
 import java.security.AccessController;
 import java.security.PrivilegedAction;
 import java.security.PrivilegedActionException;
 import java.security.PrivilegedExceptionAction;
 import java.security.SecureClassLoader;
 import java.util.Collections;
 import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.HashSet;
 import java.util.Map;
 import java.util.Set;
 import java.util.StringTokenizer;
 import java.util.logging.Level;
 import java.util.logging.Logger;

 import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
 import org.apache.tuscany.sca.extensibility.ServiceDiscoverer;
 import org.osgi.framework.Bundle;
 import org.osgi.framework.BundleContext;

 /**
  * The ServiceDiscoverer that find META-INF/services/... in installed bundles
  */
 public class OSGiServiceDiscoverer implements ServiceDiscoverer {
     private static final Logger logger = Logger.getLogger(OSGiServiceDiscoverer.class.getName());
     private BundleContext context;
     private ClassLoader classLoader;

     public OSGiServiceDiscoverer(BundleContext context) {
         this.context = context;
         this.classLoader = new ClassLoaderImpl();
     }

     /**
      * This class loader provides resource access to META-INF/services/... which is used by
      * many frameworks. OSGi Import-Package and DynmaicImport-Package headers do not support
      * split packages. Another option is to use Require-Bundle header. We can collect the list
      * of bundles and add them as required bundles to a special gateway bundle.
      */
     public class ClassLoaderImpl extends SecureClassLoader {

         public ClassLoaderImpl() {
             super(OSGiServiceDiscoverer.class.getClassLoader());
         }

         /**
          * Open a back-door to expose the META-INF/services resources
          */
         @Override
         protected URL findResource(String name) {
             int index = name.lastIndexOf('/');
             if (index == -1) {
                 return null;
             }
             String path = name.substring(0, index);
             if (path.startsWith("/")) {
                 path = path.substring(1);
             }

             if (!path.startsWith("META-INF/services")) {
                 return null;
             }

             for (Bundle bundle : context.getBundles()) {
                 URL url = bundle.getEntry(name);
                 if (url != null) {
                     return url;
                 }
             }

             return null;
         }

         /**
          * Open a back-door to expose the META-INF/services resources
          */
         @Override
         protected Enumeration<URL> findResources(String name) throws IOException {
             int index = name.lastIndexOf('/');
             if (index == -1) {
                 return null;
             }
             String path = name.substring(0, index);
             String file = name.substring(index + 1);
             if (path.startsWith("/")) {
                 path = path.substring(1);
             }

             if (!path.startsWith("META-INF/services")) {
                 return null;
             }

             Set<URL> urlSet = new HashSet<URL>();

             for (Bundle bundle : context.getBundles()) {
                 Enumeration<URL> urls = bundle.findEntries(path, file, false);
                 if (urls != null) {
                     urlSet.addAll(Collections.list(urls));
                 }
             }
             return Collections.enumeration(urlSet);
         }

     }

     public static class ServiceDeclarationImpl implements ServiceDeclaration {
         private Bundle bundle;
         private URL url;
         private String className;
         private Class<?> javaClass;
         private Map<String, String> attributes;

         public ServiceDeclarationImpl(Bundle bundle, URL url, String className, Map<String, String> attributes) {
             super();
             this.bundle = bundle;
             this.url = url;
             this.className = className;
             this.attributes = attributes;
         }

         public Map<String, String> getAttributes() {
             return attributes;
         }

         public String getClassName() {
             return className;
         }

         public Class<?> loadClass() throws ClassNotFoundException {
             if (className == null) {
                 return null;
             }
             if (javaClass == null) {
                 javaClass = loadClass(className);
             }
             return javaClass;
         }

         public Class<?> loadClass(String className) throws ClassNotFoundException {
             try {
                 return bundle.loadClass(className);
             } catch (ClassNotFoundException e) {
                 logger.severe(e.getMessage() + ": " + OSGiServiceDiscoverer.toString(bundle));
                 throw e;
             }
         }

         public URL getLocation() {
             return url;
         }

         public URL getResource(final String name) {
             return AccessController.doPrivileged(new PrivilegedAction<URL>() {
                 public URL run() {
                     return bundle.getResource(name);
                 }
             });
         }

         @Override
         public String toString() {
             StringBuffer sb = new StringBuffer();
             sb.append("Bundle: ").append(OSGiServiceDiscoverer.toString(bundle));
             sb.append(" Resource: ").append(url);
             sb.append(" Attributes: ").append(attributes);
             return sb.toString();
         }

     }

     public static String toString(Bundle b) {
         StringBuffer sb = new StringBuffer();
         sb.append(b.getBundleId()).append(" ").append(b.getSymbolicName());
         int s = b.getState();
         if ((s & Bundle.UNINSTALLED) != 0) {
             sb.append(" UNINSTALLED");
         }
         if ((s & Bundle.INSTALLED) != 0) {
             sb.append(" INSTALLED");
         }
         if ((s & Bundle.RESOLVED) != 0) {
             sb.append(" RESOLVED");
         }
         if ((s & Bundle.STARTING) != 0) {
             sb.append(" STARTING");
         }
         if ((s & Bundle.STOPPING) != 0) {
             sb.append(" STOPPING");
         }
         if ((s & Bundle.ACTIVE) != 0) {
             sb.append(" ACTIVE");
         }
         return sb.toString();

     }

     /**
      * Parse a service declaration in the form class;attr=value,attr=value and
      * return a map of attributes
      *
      * @param declaration
      * @return a map of attributes
      */
     protected static Map<String, String> parseServiceDeclaration(String declaration) {
         Map<String, String> attributes = new HashMap<String, String>();
         int index = declaration.indexOf(';');
         if (index != -1) {
             attributes.put("class", declaration.substring(0, index).trim());
             declaration = declaration.substring(index);
         } else {
             int j = declaration.indexOf('=');
             if (j == -1) {
                 attributes.put("class", declaration.trim());
                 return attributes;
             } else {
                 declaration = ";" + declaration;
             }
         }
         StringTokenizer tokens = new StringTokenizer(declaration);
         for (; tokens.hasMoreTokens();) {
             String key = tokens.nextToken("=").substring(1).trim();
             if (key == null)
                 break;
             String value = tokens.nextToken(",").substring(1).trim();
             if (value == null)
                 break;
             attributes.put(key, value);
         }
         return attributes;
     }

     public BundleContext getBundleContext() {
         return context;
     }

     /**
      * This class loader can be set as the thread context class loader for non-OSGi code
      * @return
      */
     public ClassLoader getContextClassLoader() {
         return classLoader;
     }

     @SuppressWarnings("unchecked")
     public Set<ServiceDeclaration> discover(String serviceName, boolean firstOnly) {
         boolean debug = logger.isLoggable(Level.FINE);
         Set<ServiceDeclaration> descriptors = new HashSet<ServiceDeclaration>();

         serviceName = "META-INF/services/" + serviceName;

         //        int index = serviceName.lastIndexOf('/');
         //        String path = serviceName.substring(0, index);
         //        String file = serviceName.substring(index + 1);

         // long start = System.currentTimeMillis();
         try {
             for (Bundle bundle : context.getBundles()) {
                 // Enumeration<URL> urls = bundle.findEntries(path, file, false); // This is expensive
                 final URL url = bundle.getEntry(serviceName);
                 if (url == null) {
                     continue;
                 }

                 if (debug) {
                     logger.fine("Reading service provider file: " + url.toExternalForm());
                 }
                 try {
                     // Allow privileged access to open URL stream. Add FilePermission to added to security
                     // policy file.
                     InputStream is;
                     try {
                         is = AccessController.doPrivileged(new PrivilegedExceptionAction<InputStream>() {
                             public InputStream run() throws IOException {
                                 return url.openStream();
                             }
                         });
                     } catch (PrivilegedActionException e) {
                         throw (IOException)e.getException();
                     }
                     BufferedReader reader = null;
                     try {
                         reader = new BufferedReader(new InputStreamReader(is));
                         int count = 0;
                         while (true) {
                             String line = reader.readLine();
                             if (line == null)
                                 break;
                             line = line.trim();
                             if (!line.startsWith("#") && !"".equals(line)) {
                                 String reg = line.trim();
                                 if (debug) {
                                     logger.fine("Registering service provider: " + reg);
                                 }

                                 Map<String, String> attributes = parseServiceDeclaration(reg);
                                 String className = attributes.get("class");
                                 if (className == null) {
                                     // Add a unique class name to prevent equals() from returning true
                                     className = "_class_" + count;
                                     count++;
                                 }
                                 ServiceDeclarationImpl descriptor =
                                     new ServiceDeclarationImpl(bundle, url, className, attributes);
                                 descriptors.add(descriptor);
                                 if (firstOnly) {
                                     return descriptors;
                                 }
                             }
                         }
                     } finally {
                         if (reader != null) {
                             try {
                                 reader.close();
                             } catch (IOException e) {
                                 // Ignore
                             }
                         }
                     }
                 } catch (IOException e) {
                     logger.log(Level.SEVERE, e.getMessage(), e);
                 }
             }
         } finally {
 //            long end = System.currentTimeMillis();
 //            if (true) {
 //                logger.info("Duration: " + (end - start) + " ms");
 //            }
         }
         return descriptors;

     }

 }
	/*
	* 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.tuscany.sca.extensibility.osgi;

	import java.io.BufferedReader;
	import java.io.IOException;
	import java.io.InputStream;
	import java.io.InputStreamReader;
	import java.net.URL;
	import java.security.AccessController;
	import java.security.PrivilegedAction;
	import java.security.PrivilegedActionException;
	import java.security.PrivilegedExceptionAction;
	import java.security.SecureClassLoader;
	import java.util.Collections;
	import java.util.Enumeration;
	import java.util.HashMap;
	import java.util.HashSet;
	import java.util.Map;
	import java.util.Set;
	import java.util.StringTokenizer;
	import java.util.logging.Level;
	import java.util.logging.Logger;

	import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
	import org.apache.tuscany.sca.extensibility.ServiceDiscoverer;
	import org.osgi.framework.Bundle;
	import org.osgi.framework.BundleContext;

	/**
	* The ServiceDiscoverer that find META-INF/services/... in installed bundles
	*/
	public class OSGiServiceDiscoverer implements ServiceDiscoverer {
	private static final Logger logger = Logger.getLogger(OSGiServiceDiscoverer.class.getName());
	private BundleContext context;
	private ClassLoader classLoader;

	public OSGiServiceDiscoverer(BundleContext context) {
	this.context = context;
	this.classLoader = new ClassLoaderImpl();
	}

	/**
	* This class loader provides resource access to META-INF/services/... which is used by
	* many frameworks. OSGi Import-Package and DynmaicImport-Package headers do not support
	* split packages. Another option is to use Require-Bundle header. We can collect the list
	* of bundles and add them as required bundles to a special gateway bundle.
	*/
	public class ClassLoaderImpl extends SecureClassLoader {

	public ClassLoaderImpl() {
	super(OSGiServiceDiscoverer.class.getClassLoader());
	}

	/**
	* Open a back-door to expose the META-INF/services resources
	*/
	@Override
	protected URL findResource(String name) {
	int index = name.lastIndexOf('/');
	if (index == -1) {
	return null;
	}
	String path = name.substring(0, index);
	if (path.startsWith("/")) {
	path = path.substring(1);
	}

	if (!path.startsWith("META-INF/services")) {
	return null;
	}

	for (Bundle bundle : context.getBundles()) {
	URL url = bundle.getEntry(name);
	if (url != null) {
	return url;
	}
	}

	return null;
	}

	/**
	* Open a back-door to expose the META-INF/services resources
	*/
	@Override
	protected Enumeration<URL> findResources(String name) throws IOException {
	int index = name.lastIndexOf('/');
	if (index == -1) {
	return null;
	}
	String path = name.substring(0, index);
	String file = name.substring(index + 1);
	if (path.startsWith("/")) {
	path = path.substring(1);
	}

	if (!path.startsWith("META-INF/services")) {
	return null;
	}

	Set<URL> urlSet = new HashSet<URL>();

	for (Bundle bundle : context.getBundles()) {
	Enumeration<URL> urls = bundle.findEntries(path, file, false);
	if (urls != null) {
	urlSet.addAll(Collections.list(urls));
	}
	}
	return Collections.enumeration(urlSet);
	}

	}

	public static class ServiceDeclarationImpl implements ServiceDeclaration {
	private Bundle bundle;
	private URL url;
	private String className;
	private Class<?> javaClass;
	private Map<String, String> attributes;

	public ServiceDeclarationImpl(Bundle bundle, URL url, String className, Map<String, String> attributes) {
	super();
	this.bundle = bundle;
	this.url = url;
	this.className = className;
	this.attributes = attributes;
	}

	public Map<String, String> getAttributes() {
	return attributes;
	}

	public String getClassName() {
	return className;
	}

	public Class<?> loadClass() throws ClassNotFoundException {
	if (className == null) {
	return null;
	}
	if (javaClass == null) {
	javaClass = loadClass(className);
	}
	return javaClass;
	}

	public Class<?> loadClass(String className) throws ClassNotFoundException {
	try {
	return bundle.loadClass(className);
	} catch (ClassNotFoundException e) {
	logger.severe(e.getMessage() + ": " + OSGiServiceDiscoverer.toString(bundle));
	throw e;
	}
	}

	public URL getLocation() {
	return url;
	}

	public URL getResource(final String name) {
	return AccessController.doPrivileged(new PrivilegedAction<URL>() {
	public URL run() {
	return bundle.getResource(name);
	}
	});
	}

	@Override
	public String toString() {
	StringBuffer sb = new StringBuffer();
	sb.append("Bundle: ").append(OSGiServiceDiscoverer.toString(bundle));
	sb.append(" Resource: ").append(url);
	sb.append(" Attributes: ").append(attributes);
	return sb.toString();
	}

	}

	public static String toString(Bundle b) {
	StringBuffer sb = new StringBuffer();
	sb.append(b.getBundleId()).append(" ").append(b.getSymbolicName());
	int s = b.getState();
	if ((s & Bundle.UNINSTALLED) != 0) {
	sb.append(" UNINSTALLED");
	}
	if ((s & Bundle.INSTALLED) != 0) {
	sb.append(" INSTALLED");
	}
	if ((s & Bundle.RESOLVED) != 0) {
	sb.append(" RESOLVED");
	}
	if ((s & Bundle.STARTING) != 0) {
	sb.append(" STARTING");
	}
	if ((s & Bundle.STOPPING) != 0) {
	sb.append(" STOPPING");
	}
	if ((s & Bundle.ACTIVE) != 0) {
	sb.append(" ACTIVE");
	}
	return sb.toString();

	}

	/**
	* Parse a service declaration in the form class;attr=value,attr=value and
	* return a map of attributes
	*
	* @param declaration
	* @return a map of attributes
	*/
	protected static Map<String, String> parseServiceDeclaration(String declaration) {
	Map<String, String> attributes = new HashMap<String, String>();
	int index = declaration.indexOf(';');
	if (index != -1) {
	attributes.put("class", declaration.substring(0, index).trim());
	declaration = declaration.substring(index);
	} else {
	int j = declaration.indexOf('=');
	if (j == -1) {
	attributes.put("class", declaration.trim());
	return attributes;
	} else {
	declaration = ";" + declaration;
	}
	}
	StringTokenizer tokens = new StringTokenizer(declaration);
	for (; tokens.hasMoreTokens();) {
	String key = tokens.nextToken("=").substring(1).trim();
	if (key == null)
	break;
	String value = tokens.nextToken(",").substring(1).trim();
	if (value == null)
	break;
	attributes.put(key, value);
	}
	return attributes;
	}

	public BundleContext getBundleContext() {
	return context;
	}

	/**
	* This class loader can be set as the thread context class loader for non-OSGi code
	* @return
	*/
	public ClassLoader getContextClassLoader() {
	return classLoader;
	}

	@SuppressWarnings("unchecked")
	public Set<ServiceDeclaration> discover(String serviceName, boolean firstOnly) {
	boolean debug = logger.isLoggable(Level.FINE);
	Set<ServiceDeclaration> descriptors = new HashSet<ServiceDeclaration>();

	serviceName = "META-INF/services/" + serviceName;

	// int index = serviceName.lastIndexOf('/');
	// String path = serviceName.substring(0, index);
	// String file = serviceName.substring(index + 1);

	// long start = System.currentTimeMillis();
	try {
	for (Bundle bundle : context.getBundles()) {
	// Enumeration<URL> urls = bundle.findEntries(path, file, false); // This is expensive
	final URL url = bundle.getEntry(serviceName);
	if (url == null) {
	continue;
	}

	if (debug) {
	logger.fine("Reading service provider file: " + url.toExternalForm());
	}
	try {
	// Allow privileged access to open URL stream. Add FilePermission to added to security
	// policy file.
	InputStream is;
	try {
	is = AccessController.doPrivileged(new PrivilegedExceptionAction<InputStream>() {
	public InputStream run() throws IOException {
	return url.openStream();
	}
	});
	} catch (PrivilegedActionException e) {
	throw (IOException)e.getException();
	}
	BufferedReader reader = null;
	try {
	reader = new BufferedReader(new InputStreamReader(is));
	int count = 0;
	while (true) {
	String line = reader.readLine();
	if (line == null)
	break;
	line = line.trim();
	if (!line.startsWith("#") && !"".equals(line)) {
	String reg = line.trim();
	if (debug) {
	logger.fine("Registering service provider: " + reg);
	}

	Map<String, String> attributes = parseServiceDeclaration(reg);
	String className = attributes.get("class");
	if (className == null) {
	// Add a unique class name to prevent equals() from returning true
	className = "_class_" + count;
	count++;
	}
	ServiceDeclarationImpl descriptor =
	new ServiceDeclarationImpl(bundle, url, className, attributes);
	descriptors.add(descriptor);
	if (firstOnly) {
	return descriptors;
	}
	}
	}
	} finally {
	if (reader != null) {
	try {
	reader.close();
	} catch (IOException e) {
	// Ignore
	}
	}
	}
	} catch (IOException e) {
	logger.log(Level.SEVERE, e.getMessage(), e);
	}
	}
	} finally {
	// long end = System.currentTimeMillis();
	// if (true) {
	// logger.info("Duration: " + (end - start) + " ms");
	// }
	}
	return descriptors;

	}

	}