framework.java

OSGI这是一个中间件,与UPNP齐名,是用于移植到嵌入式平台之上

/*
 * Copyright (c) 2003-2004, KNOPFLERFISH project
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials
 *   provided with the distribution.
 *
 * - Neither the name of the KNOPFLERFISH project nor the names of its
 *   contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.knopflerfish.framework;

import java.io.*;
import java.net.*;
import java.security.*;

import java.util.Collection;
import java.util.Set;
import java.util.List;
import java.util.ArrayList;
import java.util.Map;
import java.util.HashSet;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Dictionary;
import java.util.Enumeration;
import java.util.Vector;
import java.util.Locale;


import org.osgi.framework.*;
import org.osgi.service.permissionadmin.PermissionAdmin;
import org.osgi.service.packageadmin.PackageAdmin;
import org.osgi.service.startlevel.StartLevel;


/**
 * This class contains references to all common data structures
 * inside the framework.
 *
 * @author Jan Stein, Erik Wistrand
 */
public class Framework {

  /**
   * Specification version for this framework.
   */
  static final String SPEC_VERSION = "1.2";

  /**
   * AdminPermission used for permission check.
   */
  final static AdminPermission ADMIN_PERMISSION = new AdminPermission();

  /**
   * Boolean indicating that framework is running.
   */
  boolean active;

  /**
   * Set during shutdown process.
   */
  boolean shuttingdown = false;

  /**
   * All bundle in this framework.
   */
  protected Bundles bundles;

  /**
   * All listeners in this framework.
   */
  Listeners listeners = new Listeners();

  /**
   * All exported and imported packages in this framework.
   */
  Packages packages;

  /**
   * All registered services in this framework.
   */
  Services services = new Services();

  /**
   * PermissionAdmin service
   */
  PermissionAdminImpl permissions = null;

  /**
   * indicates that we use security
   */
  boolean bPermissions = false;

  /**
   * System bundle
   */
  SystemBundle systemBundle;

  BundleContextImpl systemBC;

  /**
   * Bundle Storage
   */
  BundleStorage storage;

  /**
   * Private Bundle Data Storage
   */
  FileTree dataStorage = null;

  /**
   * Main handle so that main does get GCed.
   */
  Object mainHandle;

  /**
   * The start level service.
   */
  StartLevelImpl                 startLevelService;

  /**
   * Factory for handling service-based URLs
   */
  ServiceURLStreamHandlerFactory urlStreamHandlerFactory;

  /**
   * Factory for handling service-based URL contents
   */
  ServiceContentHandlerFactory   contentHandlerFactory;

  /**
   * Magic handler for bundle: URLs
   */
  URLStreamHandler bundleURLStreamhandler;

  /**
   * Property constants for the framework.
   */
  final static String osArch    = System.getProperty("os.arch");
  final static String osName    = System.getProperty("os.name");
  final static String osVersion = System.getProperty("os.version");

  // Some tests conflicts with the R3 spec. If testcompliant=true
  // prefer the tests, not the spec
  public final static boolean R3_TESTCOMPLIANT =
    "true".equals(System.getProperty("org.knopflerfish.osgi.r3.testcompliant",
				     "false"));

  // If set to true, set the bundle startup thread's context class
  // loader to the bundle class loader. This is useful for tests
  // but shouldn't really be used in production.
  final static boolean SETCONTEXTCLASSLOADER =
    "true".equals(System.getProperty("org.knopflerfish.osgi.setcontextclassloader", "false"));

  final static boolean REGISTERBUNDLEURLHANDLER =
    "true".equals(System.getProperty("org.knopflerfish.osgi.registerbundleurlhandler", "false"));

  final static boolean REGISTERSERVICEURLHANDLER =
    "true".equals(System.getProperty("org.knopflerfish.osgi.registerserviceurlhandler", "true"));


  // Accepted execution environments. 
  static String defaultEE = "CDC-1.0/Foundation-1.0,OSGi/Minimum-1.0";

  static boolean bIsMemoryStorage = false;

  /**
   * Contruct a framework.
   *
   */
  public Framework(Object m) throws Exception {

    // guard this for profiles without System.setProperty 
    try {
      System.setProperty(Constants.FRAMEWORK_EXECUTIONENVIRONMENT, defaultEE);
    } catch (Throwable e) {
      if(Debug.packages) {
	Debug.println("Failed to set execution environment: " + e);
      }
    }

    String whichStorageImpl = "org.knopflerfish.framework.bundlestorage." + 
      System.getProperty("org.knopflerfish.framework.bundlestorage", "file") +
      ".BundleStorageImpl";

    bIsMemoryStorage = whichStorageImpl.equals("org.knopflerfish.framework.bundlestorage.memory.BundleStorageImpl");
    
    // We just happens to know that the memory storage impl isn't R3
    // compatible. And it never will be since it isn't persistent
    // by design.
    if(R3_TESTCOMPLIANT && bIsMemoryStorage) {
      throw new RuntimeException("Memory bundle storage is not compatible " + 
				 "with R3 complicance");
    }

    Class storageImpl = Class.forName(whichStorageImpl);
    storage           = (BundleStorage)storageImpl.newInstance();

    dataStorage       = Util.getFileStorage("data");
    packages          = new Packages(this);

    // guard this for profiles without Class.getProtectionDomain 
    ProtectionDomain pd = null;
    if(System.getSecurityManager() != null) {
      try {
        pd = getClass().getProtectionDomain();
      } catch (Throwable t) {
        if(Debug.classLoader) {
          Debug.println("Failed to get protection domain: " + t);
        }
      }
    }
    systemBundle      = new SystemBundle(this, pd);

    systemBC          = new BundleContextImpl(systemBundle);
    bundles           = new Bundles(this);

    systemBundle.setBundleContext(systemBC);


    
    if (System.getSecurityManager() != null) {
      bPermissions = true;
      permissions       = new PermissionAdminImpl(this);
      String [] classes = new String [] { PermissionAdmin.class.getName() };
      services.register(systemBundle,
			classes,
			permissions,
			null);

      Policy.setPolicy(new FrameworkPolicy(permissions));
    }

    String[] classes = new String [] { PackageAdmin.class.getName() };
    services.register(systemBundle,
		      classes,
		      new PackageAdminImpl(this),
		      null);


    String useStartLevel = 
      System.getProperty("org.knopflerfish.startlevel.use", "true");

    if("true".equals(useStartLevel)) {
      if(Debug.startlevel) {
	Debug.println("[using startlevel service]");
      }
      startLevelService = new StartLevelImpl(this);

      // restoreState just reads from persistant storage
      // open() needs to be called to actually do the work
      // This is done after framework has been launched.
      startLevelService.restoreState();
      
      services.register(systemBundle,
			new String [] { StartLevel.class.getName() },
			startLevelService,
			null);
    }


    mainHandle = m;

    urlStreamHandlerFactory = new ServiceURLStreamHandlerFactory(this);
    contentHandlerFactory   = new ServiceContentHandlerFactory(this);
    bundleURLStreamhandler  = new BundleURLStreamHandler(bundles);

    // Only register bundle: URLs publicly if explicitly told so
    // Note: registering bundle: URLs exports way to much. 
    if(REGISTERBUNDLEURLHANDLER) {
      urlStreamHandlerFactory
        .setURLStreamHandler(BundleURLStreamHandler.PROTOCOL,
                             bundleURLStreamhandler);
    }

    urlStreamHandlerFactory
      .setURLStreamHandler(ReferenceURLStreamHandler.PROTOCOL,
			   new ReferenceURLStreamHandler());
    
    // Install service based URL stream handler. This can be turned
    // off if there is need
    if(REGISTERSERVICEURLHANDLER) {
      try {
        URL.setURLStreamHandlerFactory(urlStreamHandlerFactory);
        
        URLConnection.setContentHandlerFactory(contentHandlerFactory);
      } catch (Throwable e) {
        Debug.println("Cannot set global URL handlers, continuing without OSGi service URL handler (" + e + ")");
        e.printStackTrace();
      }
    }
    bundles.load();
  }


  /**
   * Start this Framework.
   * This method starts all the bundles that were started at
   * the time of the last shutdown.
   *